DNA Learning Center

The mission of the DNA Learning Center is to prepare students and families to thrive in the gene age. We envision a day when all elementary students are exposed to principles of genetics and disease risk; when all high school students have the opportunity to do hands-on experiments with DNA; and when all families have access to genetic information they need to make informed health care choices.

The DNA Learning Center has had a strong web presence since the early days of the World Wide Web in 1993. We now maintain 18 sites with content and tools to enhance science education for a broad audience.

Visit Site

 

The site have Three major Links

I) Programs:

Conducting programs in three levels as PUBLIC, Educator and Student

II) Websites

In this link, providing Few Educational sites:

DNA from the Beginning

DNA Interactive & myDNAi

Genes to Cognition Online & Simple Mapper

Inside Cancer & Inside Cancer Teacher Center

Image Archive on the American Eugenics Movement

Learn About SMA NEW!

Weed to Wonder

Your Genes, Your Health

Lab & Bioinformatics Sites:

BioServers

DNA Barcoding 101 NEW!

DNALC Kits

DNA Subway

Dynamic Gene

GENE BOY

Genetic Origins

Greenomes

Lab Center

Silencing Genomes

Urban Barcode Project

III) Resources

In this link they are providing,

Spotlight Collections

We are enhancing our most popular resources by building collections around them. First up: Polymerase Chain Reaction!

Biology Animation Library

The DNA Learning Center has been developing multimedia animation programs since 1990. These popular programs feature some of the most common molecular processes such as PCR, sequencing, and DNA restriction. View online or download for play from your computer.

3-D Animation Library

Stunning three-dimensional visualizations of cellular and molecular processes. Journey inside a cell as you follow proteins and learn about cellular interactions in Cell Signals. Zoom along a three-dimensional rendering of 650,000 nucleotides of human chromosome 11 to see how little actually encodes protein in Chromosome 11 Flyover. DNA translation, transcription, and replication, and chromosome packaging are presented in several animations featured on DNA Interactive (created by Drew Berry).

G2C Online 3-D Brain

An interactive brain map that allows users to rotate the brain in three-dimensional space. Individual maps of 29 structures include information on brain damage, case studies, and links to modern research.

Gene Screen App

Gene Screen is a fun way to learn how recessive genetic traits and diseases are inherited and find out which genetic diseases are more prevalent where your ancestors came from. Info on some recessive diseases and screening programs also included. Download the free app today for your iPhone/iPod Touch and iPad.

Nobel Laureates in DNA from the Beginning

Each year a select few scientists are recognized for their work by the Nobel Foundation. We feature many of these scientists on our DNA from the Beginning site. We have gathered all of the prize winners here; follow the links for animated explanations of their groundbreaking work.

DNA Today

Join Dave Micklos, Jan Witkowski, and staff commentators for a lively discussion of DNA in the news from world-renowned Cold Spring Harbor Laboratory!

Gene Boy

Also found under our websites header, Gene Boy is a simple, multifunction DNA sequence analysis tool; analyze stored sequences or upload your own DNA sequence.

Building Modern Internet Sites for Science Education:
Insights from Science, Technology, and Education

This paper condenses insights gained during a three-day workshop of 30 experts and opinion leaders from diverse fields – including neuroscience, cognitive science, network theory, knowledge management, science education, and technology convergence. The quick insights are a useful laundry list for anyone creating a modern Internet site on science education, while the deeper insights give a sense of what is on the minds of people who are leading the effort to use the Internet to connect people in real-time communities of common interest. Available in MS Word and PDF.

Nucleotide Sequences of pAMP, pKAN, and pBLU Plasmids

These common plasmids are used in our laboratory protocols. Link for a reference map and nucleotide sequence of each plasmid.

Products

Get information about our DNALC-produced textbook, DVD, and CD-ROM set available for purchase through the Cold Spring Harbor Laboratory Press.

Resources available from Cold Spring Harbor Laboratory Press

Resources available from Cold Spring Harbor Laboratory Press

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DNA interactive site for animated learning

DNA interactive site for animated learning

Visit the site

Synopsis of the site:

• Timeline  
• Code     
• Manipulation 
• Genome     
• Applications    
• Chronicle    
• myDNAi  
• myDNAi Teacher Guide 
• The Making of DNA Interactive

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Biochemistry of Metabolism

Biochemistry of Metabolism notes and Information for Students

Part I

Sugars & Polysaccharides
Lipids & Membranes
Bioenergetics
Membrane Transport
K⁺ Channels
Calcium Signals
Signal Transduction
Glycolysis & Fermentation
Glycogen Metabolism
Gluconeogenesis
Krebs Cycle
Electron Transfer Chain
Chemiosmotic Coupling
F₁F_o ATPase

 

Part II

Pentose Phosphate Pathway
Calvin Cycle
Fatty acid catabolism
Fatty acid synthesis
Eicosanoid synthesis
Cholesterol synthesis
Lipoproteins
Amino acid catabolism - N
Amino acid catabolism - C
Heme synthesis
tRNA and ribosomes
Protein synthesis
Protein degradation

Clinical Biochemistry 

Actin cytoskeleton
Myosin
Microtubules
Microtubule motors
Review: Basic Concepts
of Protein Structure

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Basics of Biochemical Techniques

Some of the Biochemical techniques are given  here.

1. Biochemical Tests:

These five tests identify the main biologically important chemical compounds. For each test take a small amount of the substance to test, and shake it in water in a test tube. If the sample is a piece of food, then grind it with some water in a pestle and mortar to break up the cells and release the cell contents. Many of these compounds are insoluble, but the tests work just as well on a fine suspension.

• Starch (iodine test). To approximately 2 cm³ of test solution add two drops of iodine/potassium iodide solution. A blue-black colour indicates the presence of starch as a starch-polyiodide complex is formed. Starch is only slightly soluble in water, but the test works well in a suspension or as a solid.
• Reducing Sugars (Benedict's test). All monosaccharides and most disaccharides (except sucrose) will reduce copper (II) sulphate, producing a precipitate of copper (I) oxide on heating, so they are called reducing sugars. Benedict’s reagent is an aqueous solution of copper (II) sulphate, sodium carbonate and sodium citrate. To approximately 2 cm³ of test solution add an equal quantity of Benedict’s reagent. Shake, and heat for a few minutes at 95°C in a water bath. A precipitate indicates reducing sugar. The colour and density of the precipitate gives an indication of the amount of reducing sugar present, so this test is semi-quantitative. The original pale blue colour means no reducing sugar, a green precipitate means relatively little sugar; a brown or red precipitate means progressively more sugar is present.
• Non-reducing Sugars (Benedict's test). Sucrose is called a non-reducing sugar because it does not reduce copper sulphate, so there is no direct test for sucrose. However, if it is first hydrolysed (broken down) to its constituent monosaccharides (glucose and fructose), it will then give a positive Benedict's test. So sucrose is the only sugar that will give a negative Benedict's test before hydrolysis and a positive test afterwards. First test a sample for reducing sugars, to see if there are any present bef7ore hydrolysis. Then, using a separate sample, boil the test solution with dilute hydrochloric acid for a few minutes to hydrolyse the glycosidic bond. Neutralise the solution by gently adding small amounts of solid sodium hydrogen carbonate until it stops fizzing, then test as before for reducing sugars.
• Lipids (emulsion test). Lipids do not dissolve in water, but do dissolve in ethanol. This characteristic is used in the emulsion test. Do not start by dissolving the sample in water, but instead shake some of the test sample with about 4 cm³ of ethanol. Decant the liquid into a test tube of water, leaving any undissolved substances behind. If there are lipids dissolved in the ethanol, they will precipitate in the water, forming a cloudy white emulsion.
• Protein (biuret test). To about 2 cm³ of test solution add an equal volume of biuret solution, down the side of the test tube. A blue ring forms at the surface of the solution, which disappears on shaking, and the solution turns lilac-purple, indicating protein. The colour is due to a complex between nitrogen atoms in the peptide chain and Cu²⁺ ions, so this is really a test for peptide bonds.

2. Chromatography:
Chromatography is used to separate pure substances from a mixture of substances, such as a cell extract. It is based on different substances having different solubility in different solvents. A simple and common form of chromatography uses filter paper.

1. Pour some solvent into a chromatography tank and seal it, so the atmosphere is saturated with solvent vapour. Different solvents are suitable for different tasks, but they are usually mixtures of water with organic liquids such as ethanol or propanone.
2. Place a drop of the mixture to be separated onto a sheet of chromatography paper near one end. This is the origin of the chromatogram. The spot should be small but concentrated. Repeat for any other mixtures. Label the spots with pencil, as ink may dissolve.
3. Place the chromatography sheet into the tank so that the origin is just above the level of solvent, and leave for several hours. The solvent will rise up the paper by capillary action carrying the contents of the mixture with it. Any solutes dissolved in the solvent will be partitioned between the organic solvent (the moving phase) and the water, which is held by the paper (the stationary phase). The more soluble a solute is in the solvent the further up the paper it will move.
4. When the solvent has nearly reached the top of the paper, the paper is removed and the position of the solvent front marked. The chromatogram may need to be developed to make the spots visible. For example amino acids stain purple with ninhydrin.
5. The chromatogram can be analysed by measuring the distance travelled by the solvent front, and the distance from the origin to the centre of each spot. This is used to calculate the R_f (relative front) value for each spot:

An R_f value is characteristic of a particular solute in a particular solvent. It can be used to identify components of a mixture by comparing to tables of known R_f values.

 

Sometimes chromatography with a single solvent is not enough to separate all the constituents of a mixture. In this case the separation can be improved by two-dimensional chromatography, where the chromatography paper is turned through 90° and run a second time in a second solvent. Solutes that didn't separate in one solvent will separate in another because they have different solubility.

There are many different types of chromatography.

• Paper chromatography is the simplest, but does not always give very clean separation.
• Thin layer chromatography (tlc) uses a thin layer of cellulose or silica coated onto a plastic or glass sheet. This is more expensive, but gives much better and more reliable separation.
• Column chromatography uses a glass column filled with a cellulose slurry. Large samples can be pumped through the column and the separated fractions can be collected for further experiments, so this is preparative chromatography as opposed to analytical chromatography.

• High performance liquid chromatography (HPLC) is an improved form of column chromatography that delivers excellent separation very quickly.
• Electrophoresis uses an electric current to separate molecules on the basis of charge. It can also be used to separate on the basis of molecular size, and as such is used in DNA sequencing.

 

3. Cell Fractionation:

This means separating different parts and organelles of a cell, so that they can be studied in detail. All the processes of cell metabolism (such as respiration or photosynthesis) have been studied in this way. The most common method of fractionating cells is to use differential centrifugation:

A more sophisticated separation can be performed by density gradient centrifugation. In this, the cell-free extract is centrifuged in a dense solution (such as sucrose or caesium chloride). The fractions don't pellet, but instead separate out into layers with the densest fractions near the bottom of the tube. The desired layer can then be pipetted off. This is the technique used in the Meselson-Stahl experiment (module 2) and it is also used to separate the two types of ribosomes. The terms 70S and 80S refer to their positions in a density gradient.

4. Enzyme Kinetics:

This means measuring the rate of enzyme reactions.

• Firstly you need a signal to measure that shows the progress of the reaction. The signal should change with either substrate or product concentration, and it should preferably be something that can be measured continuously. Typical signals include colour changes, pH changes, mass changes, gas production, volume changes or turbidity changes. If the reaction has none of these properties, it can sometimes be linked to a second reaction which does generate one of these changes.

• If you mix your substrate with enzyme and measure your signal, you will obtain a time-course. If the signal is proportional to substrate concentration it will start high and decrease, while if the signal is proportional to product it will start low and increase. In both cases the time-course will be curved (actually an exponential curve).

• How do you obtain a rate from this time-course? One thing that is not a good idea is to measure the time taken for the reaction, for as the time-course shows it is very difficult to say when the reaction ends: it just gradually approaches the end-point. A better method is to measure the initial rate - that is the initial slope of the time-course. This also means you don't need to record the whole time-course, but simply take one measurement a short time after mixing.

• Repeat this initial rate measurement under different conditions (such as different substrate concentrations) and then plot a graph of rate vs. the factor. Each point on this second graph is taken from a separate initial rate measurement (or better still is an average of several initial rate measurements under the same conditions). Draw a smooth curve through the points.

  Be careful not to confuse the two kinds of graph (the time-course and rate graphs) when interpreting your data.

  One useful trick is to dissolve the substrate in agar in an agar plate. If a source of enzyme is placed in the agar plate, the enzyme will diffuse out through the agar, turning the substrate into product as it goes. There must be a way to distinguish the substrate from the product, and the reaction will then show up as a ring around the enzyme source. The higher the concentration of enzyme, the higher the diffusion gradient, so the faster the enzyme diffuses through the agar, so the larger the ring in a given time. The diameter of the ring is therefore proportional to the enzyme concentration. This can be done for many enzymes, e.g. a protein agar plate can be used for a protease enzyme, or a starch agar plate can be used for the enzyme amylase.

5. Microscopy

Of all the techniques used in biology microscopy is probably the most important. The vast majority of living organisms are too small to be seen in any detail with the human eye, and cells and their organelles can only be seen with the aid of a microscope. Cells were first seen in 1665 by Robert Hooke (who named them after monks' cells in a monastery), and were studied in more detail by Leeuwehoek using a primitive microscope.

Units of measurement. The standard SI units of measurement used in microscopy are:

metre (m)               = 1 m

millimetre (mm)   = 10^-3 m

micrometre        = 10^-6 m

nanometre (nm) = 10^-9 m

picometre (pm)  = 10^-12 m

angstrom (Å⁰)     = 10^-10 m (obsolete)

Magnification and Resolving Power. By using more lenses microscopes can magnify by a larger amount, but this doesn't always mean that more detail can be seen. The amount of detail depends on the resolving power of a microscope, which is the smallest separation at which two separate objects can be distinguished (or resolved). It is calculated by the formula:

where lambda is the wavelength of light, and n.a. is the numerical aperture of the lens (which ranges from about 0.5 to 1.4). So the resolving power of a microscope is ultimately limited by the wavelength of light (400-600nm for visible light). To improve the resolving power a shorter wavelength of light is needed, and sometimes microscopes have blue filters for this purpose (because blue has the shortest wavelength of visible light).

Different kinds of Microscope.

Light Microscope. This is the oldest, simplest and most widely-used form of microscopy. Specimens are illuminated with light, which is focussed using glass lenses and viewed using the eye or photographic film. Specimens can be living or dead, but often need to be stained with a coloured dye to make them visible. Many different stains are available that stain specific parts of the cell such as DNA, lipids, cytoskeleton, etc. All light microscopes today are compound microscopes, which means they use several lenses to obtain high magnification. Light microscopy has a resolution of about 200 nm, which is good enough to see cells, but not the details of cell organelles. There has been a recent resurgence in the use of light microscopy, partly due to technical improvements, which have dramatically improved the resolution far beyond the theoretical limit. For example fluorescence microscopy has a resolution of about 10 nm, while interference microscopy has a resolution of about 1 nm.

Electron Microscope. This uses a beam of electrons, rather than electromagnetic radiation, to "illuminate" the specimen. This may seem strange, but electrons behave like waves and can easily be produced (using a hot wire), focussed (using electromagnets) and detected (using a phosphor screen or photographic film). A beam of electrons has an effective wavelength of less than 1 nm, so can be used to resolve small sub-cellular ultrastructure. The development of the electron microscope in the 1930s revolutionised biology, allowing organelles such as mitochondria, ER and membranes to be seen in detail for the first time.

The main problem with the electron microscope is that specimens must be fixed in plastic and viewed in a vacuum, and must therefore be dead. Other problems are that the specimens can be damaged by the electron beam and they must be stained with an electron-dense chemical (usually heavy metals like osmium, lead or gold). Initially there was a problem of artefacts (i.e. observed structures that were due to the preparation process and were not real), but improvements in technique have eliminated most of these.

There are two kinds of electron microscope. The transmission electron microscope (TEM) works much like a light microscope, transmitting a beam of electrons through a thin specimen and then focussing the electrons to form an image on a screen or on film. This is the most common form of electron microscope and has the best resolution. The scanning electron microscope (SEM) scans a fine beam of electron onto a specimen and collects the electrons scattered by the surface. This has poorer resolution, but gives excellent 3-dimentional images of surfaces.

• X-ray Microscope. This is an obvious improvement to the light microscope, since x-rays have wavelengths a thousand time shorter than visible light, and so could even be used to resolve atoms. Unfortunately there are no good x-ray lenses, so an image cannot be focussed, and useable x-ray microscopes do not yet exist. However, x-rays can be used without focussing to give a diffraction pattern, which can be used to work out the structures of molecules, such as those of proteins and DNA.

• Scanning Tunnelling Microscope (or Atomic Force Microscope). This uses a very fine needle to scan the surface of a specimen. It has a resolution of about 10 pm, and has been used to observe individual atoms for the first time.

Comparison of Light and Electron Microscopes:

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How do NADP+ and NADPH differ from NAD+ and NADH?

These pairs of molecules are identical except for the presence of a phosphate group at the 2′ position on the ribose moiety. This is not a high-energy phosphate but rather a molecular tag that enables enzymes to discriminate between the two forms of redox compound. In higher animals there do not appear to be any NADH transferase enzymes that catalyze direct transfer of hydrogen atoms from NADH to NADP+ or from NADPH to NAD+.

NADH and NADPH are equivalent in terms of their standard redox potentials, but because redox enzymes are usuallyselective for one or the other of them, two distinct pools of reductants exist. NADH is used as a source of reducing equivalents for the electron transport chain (ETC) while NADPH provides reducing equivalents for many biosyntheticreactions. Hence, even within a single spatial compartment such as the cytoplasm, the NADH to NAD+ ratio can be very low, favoring oxidation of fuels, while simultaneously the NADPH to NADP+ ratio can be very high, facilitating biosynthesis.

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Check your Life Science knowledge with this Test in CSIR-UGC-NET

Just Click “Click Here” link and give ur name & Email ID. this test help by biotecnika.org

Test 1
Generalised full syllabus test on all india basis
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Test 2
Generalised full syllabus test on all india Basis
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Test 3
Cell organisation,Chromosomes,DNA-structure and replication,Evolution, RDT and genetic engineering

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Test 4

• Proteins-
  • structure,
  • classification &
  • properties,
• Carbohydrates,
• Fat metabolism,
• Nitrogen metabolism
• Vitamins

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Test 5

• Enzymes,Coenzymes (Activators,Inhibitors)
• Thermodynamics
• Enzyme Kinetics
• Enzyme activity regulation
• pH (H.H Equation)

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Test 6

• Nucleic Acid Structure
• Genetic code
• DNA Repair
• DNA replication
• Transcription
• Translation

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Test 7

• Cell division
• cell organelle
  • structure
  • Function
• Cell cell Interaction
• Structure of Prokaryotic and Eukaryotic cell

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Test 8

• Bioenergetics,
• glycolysis,
• oxidative phosphorylation,
• coupled reaction,
• group transfer,
• biological energy transducers

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Test 9

• Amino Acid Metabolism
• Cordinated control of metabolism
• Biosynthesis of Purines & Pyrimidines
• Oxidation of Lipids
• Biosynthesis of Fatty acid, Triglyceride, Phospholipid and Sterol.

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Test 10
Cancer: Genetic rearrangements in progenitor cells, oncogenes, tumor suppressor genes, cancer and the cell cycle, virus-induced cancer, metastasis, interaction of cancer cells with normal cells, apoptosis, therapeutic interventions of uncontrolled cell growth.
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Test 11
COMMON ELEMENTRY COMPUTER SCIENCE: dealing with basic computer awareness and uses
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Test 12

• Principals and applications of Gel Filtration
• Ion Exchange and affinity Chromatography
• Thin layer and Gas chromatography
• HPLC
• Principals and applicationsNucleic Acid Hybridization and cot curve
• Sequencieng of Proteins and nucleic acid
• Southern, South-western, northern blotting
• PCR

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ALL THE BEST

Source: biotecnika.org/net-jrf-coaching

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APSET Notification 2012

OSMANIA UNIVERSITY, HYDERABAD- 500 007

AP-SET-2012 NOTIFICATION

Applications are invited by Osmania University from eligible candidates to appear for the Andhra Pradesh State Eligibility Test (AP-SET), 2012 for recruitment as Assistant Professors/Lecturers in various Universities/Degree Colleges/ Institutions of Higher Education in Andhra Pradesh. The Test will be held on 27.7.2012 (Friday) for 24 subjects approved by University Grants Commission falling under Humanities, Social Sciences and Sciences in 12 Centers in the State.

Eligibility Criteria to appear for the AP-SET-2012 :

The candidate must have a Master’s Degree from a UGC recognized university with minimum 55% marks for general/BC candidates and 50% marks for SC/ST/PH/VH. Candidates who are appearing in the final year of their Post-Graduate examination may also appear in this examination. For details of subjects, scheme of test and examination centers see the information provided in www.apset.org, and www.osmania.ac.in

Important dates for AP-SET-2012 :

submission of on-line applications : 3.5.2012 to 30.5.2012

With late fee of Rs.100 : 1.6.2012 to   5.6.2012

With late fee of Rs.200 : 6.6.2012 to 10.6.2012

Date of Examination : 27.7. 2012(Friday) from 9.30 am to 4.30 pm

Registration Fee:

Category Cost (Rupees)

OC : 700/-

BC : 500/-

SC/ST/PH/VH. : 250/-

Registration fee has to be paid through Bank Challan by down loading from AP- SET website.

Eligibility Conditions for AP-SET-2012 :

3.1 Only those candidates who have completed or are pursuing the final year of PG degree in related subjects are eligible to appear AP. SET. Others need not apply.

3.2 Candidates who have secured atleast 55% marks (without grace or rounding off) in the Master’s degree ( for OC & BC) and 50% marks (without grace or rounding off) for   Scheduled Caste (SC)/Scheduled Tribes (ST)/Physically Challanged (PH)/VH category candidates  are eligible for this examination.

3.3 Candidates who have appeared (or) will be appearing at the qualifying Master’s Degree examination and whose result is still      awaited (or) candidates whose examinations have been delayed may also apply for this test. However, such candidates will be admitted provisionally and shall be considered eligible for award of Lectureship eligibility only after they have passed their Master’s Degree examination (or) equivalent with atleast 55% marks (50% in case of SC/ST/PH/VH candidates). Such candidates must obtain their P.G degree mark sheet within one year from the date of SET with the required percentage of  marks, failing which they will be treated as disqualified.

3.4 Ph.D. degree holders whose Master’s level examination has been completed (irrespective of date of declaration of result) shall be eligible for relaxation of 5% of marks from 55% to 50% to appear in the AP.SET Examination.

3.5 Candidates have to appear for AP-SET in the subject of their Post-Graduation only. In case the subject of a candidate is not included in the list of SET subjects, the candidate may appear in UGC-NET / UGC-CSIR NET which is held twice a year.

3.6 The candidates who qualify in the test are eligible to apply for the post of Asst. Professors / Lecturers in various universities and degree colleges of higher education in Andhra Pradesh. They will be given a pass-certificate and the validity period of certificate is forever.

3.7 Candidates other than general category are required to mention of their social status (BC/SC/ST/PH/VH) in the online application form. The candidates in their own interest must satisfy themselves about their eligibility for the test. In case their ineligibility is detected by the Agency at any stage, their candidature will be cancelled and they shall be liable for legal action.

3.8 Candidates may note that the verification of eligibility conditions with reference to the documents (PG qualification certificates, caste certificates and certificates related to PH/VH) as may be called for will be taken up only after the candidate has qualified in the test. If in the event of the candidate being found ineligible at any stage for the award due to any reason, the award may be withdrawn by AP.SET. 

3.9 Candidates should note that their candidature is provisional. The mere fact that an admission card has been issued to a candidate will not imply that the university has finally accepted his/her candidature. Candidates may note that their candidature will be deemed final upon verification of eligibility conditions.

3.10 The candidates will not be given any mark sheet from the AP.SET office whether they have qualified or not qualified.

   No revaluations of papers are allowed for SET Examination. The SET agency will issue certificates to the qualified candidates only after careful verification of the concerned certificates of the candidate.

3.11 The same photograph of the candidate which is printed on the hall ticket will also be Printed on the certificate to be issued by the Office of the AP.SET.

4.Age Limit: No upper age limit.

5. Number of Chances: A candidate can avail any number of chances. 

6. Exemption (Eligibility for Lectureship):

6.1 AP-SET shall remain the minimum eligibility condition for recruitment and appointment of Assistant Professors in universities/colleges/institutions. However, the candidates, who have been awarded a Ph. D. Degree in accordance with the University Grants Commission (Minimum Standards and Procedure for Award of Ph.D. Degree) Regulations, 2009, shall be exempted from the requirement of the minimum eligibility condition of AP.SET for recruitment and appointment of Assistant Professor or equivalent positions in universities/ colleges/ institutions.

6.2 For AP- SET Candidates: The candidates who have cleared the State Eligibility Test (AP-SET) accredited by UGC for eligibility for Lectureship held prior to 1st June 2002, are exempted from appearing in NET, being eligible to apply for Lectureship anywhere in India. For AP- SET held from 1st June 2002 onwards, the qualified candidates are eligible to apply for the post of Lecturer only in the universities/ colleges belonging to the state from where they have cleared their AP-SET.

AP-SET Syllabus for AP-SET-2012 :

• As per the UGC guidelines the CSIR/UGC-NET syllabus has been adopted for the conduct of AP-SET for all  the 24 subjects for which accreditation is given by UGC

• Question paper for paper-I is common for all subjects in which SET is conducted and it will be bi-lingua l(English and Telugu). Paper-ll and paper-lll of certain subjects will also be bi-lingual and details are furnished below. The syllabus for paper-l, paper-ll and paper-lll will not send to the candidates by the University.

Scheme of Examination for AP-SET-2012 :

The APSET will be conducted in objective mode. The test will consist of three papers. All the three papers will consist of multiple choice questions and will be held on the day of examination in two separate sessions as under:

Paper-I: General paper on Teaching and Aptitude:

This paper shall be of general nature intended to assess the teaching/research aptitude of the candidate. It will be primarily designed to test reasoning ability, comprehension, divergent thinking and general awareness of the candidate. There will be sixty (60) multiple-choice questions of two marks each of out of which the candidate will be required to answer any fifty (50). In the event of the candidate attempting more than fifty questions, the first fifty questions attempted by the candidate will be evaluated.

Paper-II: Subject Paper :

This paper consists of multiple- choice questions based on the subject selected by the candidates .The paper will consists of fifty (50) multiple choice questions. The candidates will have to answer all the questions. The candidates will have to mark their response for each question on the computer coded optical mark reader (OMR) answer sheet provided along with the test booklet

Paper-III: Subject Paper (in depth questions):

This paper consists of multiple choice questions based on the syllabus of the subject selected by the candidates. The paper will consist of seventy-five (75) multiple-choice questions. The candidates will be required to answer all the questions and have to mark their response for each question on the computer coded optical mark reader(OMR)answer sheet provided along with the test booklet.

Paper-III of all the subjects covers all the specializations of that subject in which SET is conducted. For example Paper-III of Chemical Sciences covers all specializations such as Analytical Chemistry, Inorganic Chemistry, Organic Chemistry, Physical Chemistry, Marine Chemistry, Medicinal Chemistry, Applied Chemistry, Nuclear Chemistry, & Bio-inorganic Chemistry.

Similarly, Paper-III of Earth Sciences covers such as Geology, Applied Geology, MS Geology, Geophysics, Meteorology, Marine Geology, Petroleum Geology, Geo-Informatics, Applied Geochemistry & Oceanography.
Paper-III of Life Sciences covers all specializations such as Botany, Biochemistry, Biotechnology, Genetics, Microbiology, Zoology, Fishery Science, Animal Biology & Marine Biology.

Paper-III of Mathematical Sciences covers all specializations such as Mathematics, Applied Mathematics, Statistics & Applied Statistics.

Paper-III of Physical Sciences covers all specializations such as Atomic & Molecular Physics, Classical Dynamics, Condensed Matter Physics, Electromagnetics, Experimental Design, Electronics, Nuclear Physics, Space Physics, Particle Physics, Quantum Physics & Thermodynamics.

• A candidate who does not appear for Paper-I and Paper-II will not be permitted for Paper-III.

• There will be No negative Marking

• The candidates are required to obtain minimum marks separately in Paper-I, Paper-II and Paper-III as given below:

• Only such candidates who obtain the minimum required marks in each paper, separately as mentioned above, will be considered for the final preparation of results. 

• However, the qualifying criteria and eligibility for Lectureship shall be decided by the Moderation Committee of AP. SET.  The syllabus of Paper-I, Paper-II and Paper-III will be the same as UGC-CSIR and UGC-NET

• The candidates will be allowed to carry a carbon printout of the OMR Response Sheets with them on conclusion of examinations.

EXAMINATION CENTERS OF AP-SET:

Centre Code Examination Centre

11.  Hyderabad

12 Warangal

13 Nizamabad

14 Nalgonda

15 Visakhapatnam

16 Guntur

17 Rajahmundry

18 Nellore

19 Tirupati

20 Anantapur

21 Kadapa

22 Kurnool

Note: No request for change of center will be entertained under any  circumstances.

Apply Online

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Download Syllabus

Important Dates:

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WHO says cell phone use can cause brain cancer

LONDON (Reuters) - Using a mobile phone may increase the risk of certain types of brain cancer in humans and consumers should consider ways of reducing their exposure, World Health Organization (WHO) cancer experts said on Tuesday.

A working group of 31 scientists from 14 countries meeting at the WHO's International Agency for Research on Cancer (IARC) said a review of all the available scientific evidence suggested cell phone use should be classified as "possibly carcinogenic".

The classification could prompt the U.N. health body to look again at its guidelines on mobile phones, the IARC scientists said, but more research is needed before a more definitive answer on any link can be given.

The WHO had previously said there was no established evidence for a link between cell phone use and cancer.

"After reviewing essentially all the evidence that is relevant ... the working group classified radiofrequency electromagnetic fields as possibly carcinogenic to humans," Jonathan Samet, chair of the IARC group, said in a telebriefing.

He said some evidence suggested a link between an increased risk for glioma, a type of brain cancer, and mobile phone use.

The decision comes after a study published last year which looked at almost 13,000 cell phone users over 10 years found no clear answer on whether the mobile devices cause brain tumours.

The decision has been keenly awaited by mobile phone companies and by campaign groups who have raised concerns about whether cell phones might be harmful to health.

Use of cell phones use has increased dramatically since their introduction in the early-to-mid 1980s. About 5 billion mobile phones are currently in use worldwide.

(Reporting by Kate Kelland, editing by Alison Williams)

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Here is the first man to be cured of HIV- AIDS

Timothy Ray Brown, 45, from San Francisco Bay Area, is in the news – as the first man cured of HIV- AIDS. “I think so,” he calmly tells his interviewers who ask if he actually is cured.

Brown has been facing cameras, gun mikes and diagnostic kits ever since the publication of a research paper on his unique case in the journal Blood in December 2010.

The researchers led by Kristina Allers and Gero Hutter at Charite University Medicine Berlindocumented what can be dubbed as a miracle.

The successful reconstitution of a set of white blood cells that the HIV eats up in Brown’s body is a “very rare” occurrence, they noted.

Brown, who was tested HIV back in 1995 in Germany, was later diagnosed with another disease — leukemia or blood cancer that involves an abnormal increase in white blood cell.

He was treated with bone marrow stem cell transplant — a cure for blood cancer. The stem cells came from a donor with a rare gene mutation that involves immunity to HIV — again a rare occurrence.

The mechanism involved special white blood cells called CD4+ helper T cells.  When a dangerous material like a bacterium or a virus is detected in the body, immune cells immediately stimulate these special cells.

The helper T cells further activate and direct other immune cells to fight the disease. HIV specifically attacks helper T cells, making the body unable to launch a counter offensive against invaders.

Hence, AIDS patients suffer from other lethal infections. The researchers in Berlin showed that after stem cell therapy Brown’s body had reconstitution of CD4+ T cells at a systemic level and specifically in his gut mucosal immune system.

“While the patient remains without any sign of HIV infection,” they wrote. Brown has quit taking his HIV medication. The secret is that if the white cells could be manipulated to a state in which they are no longer infected or infectable by HIV that would mean a functional cure.

Researchers, however, have warned that though the study offers promise, it is not a surefire cure from the dreaded disease — transplants are risky, and this involved a very rare transplant. Brown is a rather lucky man. He said in a recent interview that appeared in the San Francisco media about his cure: “It makes me very happy — very, very happy.”

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About the metabolic fate of the carbon skeleton of amino acids

An amino acid that yields acetoacetyl CoA during the catabolism of its carbon skeleton would be considered:

a)  glycogenic

b)     ketogenic

c)      glycogenic and ketogenic

d)     neither glycogenic nor ketogenic

e)     essential

f)       non essential

Answer is

Answer: (b) Ketogenic (Since the question only make reference to acetoacetyl CoA, we assume that it is the final product of the catabolism of this amino acid and no glucogenic metabolites are produced.)

Amino acids are used for different purposes in our body. Most of the metabolic pool of amino acids is used as building blocks of proteins, and a smaller proportion is used to synthesize specialized nitrogenated molecules as epinephrine and norepinephrine, neurotransmitters and the precursors of purines and pyrimidines.

Since amino acids can not be stored in the body for later use, any amino acid not required for immediate biosynthetic needs is deaminated and the carbon skeleton is used as metabolic fuel (10-20 % in normal conditions) or converted into fatty acids via acetyl CoA.

The main products of the catabolism of the carbon skeleton of the amino acids are pyruvate, oxalacetate, a-ketoglutarate, succinyl CoA, fumarate, acetyl CoA and acetoacetyl CoA.

When carbohydrates are not available (starvation, fasting) -or cannot be used properly, as in diabetes mellitus, amino acids can become a primary source of energy by oxidation of their carbon skeleton, but also by becoming an important source of glucose for those tissues that only can use this sugar as metabolic fuel.

The formation of glucose from amino acids (gluconeogenesis) in liver and kidney is intensified during starvation and this process becomes the most important source of glucose for the brain, RBC and other tissues.

Amino acids in skeletal proteins can be used, in a situation of prolonged starvation as an “emergency” energy store that can yield 25000 kcal.

Amino acids can be classified according to the metabolic fate of the carbon skeleton in:

• ketogenic,
• glucogenic
• ketogenic and glucogenic

Ketogenics: Amino acids that yield acetyl CoA or acetoacetyl CoA ( e.g. they do not produce metabolites that can be converted in glucose). 

Lysine and Leucine are the only amino acids that are exclusively ketogenics.

Glucogenic: Amino acids whose catabolism yields to the formation of Pyruvate or Krebs Cycle metabolites, that can be converted in glucose through gluconeogenesis (Remember the pathway: pyruvate-àoxalacetate-à (P) enol pyruvate…etc.).

Glucogenic amino acids  are: Alanine, Arginine, Asparagine, Aspartate, Cysteine, Glutamate, Glycine, Histidine, Methionine, Proline, Serine, and Valine

Glucogenic and ketogenic: Amino acids that yield some products that can become glucose and others that yields acetyl CoA or Acetoacetyl CoA.

Amino acids of this kind are Isoleucine, Phenylalanine, Tryptophan, Tyrosine and Threonine.

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PCR Saliva Tests Useful for Congenital CMV Screening

Real-time polymerase-chain-reaction (PCR) assays of saliva samples are accurate for detecting congenital cytomegalovirus infection in newborns, researchers found.

Assays using both liquid and dried saliva had high sensitivity and specificity for identifying the infection, with positive predictive values over 90% and negative predictive values at or near 100%, according to Suresh Boppana, MD, of the University of Alabama at Birmingham, and colleagues.

Unlike the standard rapid cultures of saliva and urine samples, the PCR assays can be automated and adapted for widespread screening, which could identify babies who would benefit from early intervention to mitigate the effects on speech and language development of any cytomegalovirus-related hearing loss, the researchers reported in the June 2 issue of the New England Journal of Medicine.

Although screening would allow for early identification, the standard culture method performed on saliva or urine samples cannot be automated, which limits utility for large-scale screening. Most infants with congenital cytomegalovirus infection are not identified because the infection is asymptomatic and testing is not routine.

A previous study by Boppana's group showed the dried-blood-spot PCR assays identified fewer than 40% of cytomegalovirus-infected newborns, so the researchers compared real-time PCR assays (using either liquid or dry saliva samples) with rapid culture at seven U.S. hospitals.

Of those screened with the liquid-saliva PCR assay, 85 infants (0.5%) were positive on both rapid culture and the PCR assay. Another eight infants were positive on the PCR assay but not on culture. Of the 34,989 screened, 0.5% were positive for cytomegalovirus using at least one of the three screening methods.

Of the newborns screened with the dried-saliva PCR assay, 76 (0.44%) were positive on rapid culture -- 74 of whom were also positive on the PCR assay. Another eight infants were positive on the PCR assay only. The sensitivity and specificity of the PCR assay were 100% and 99.9%, respectively, and the positive and negative predictive values were 91.4% and 100%, respectively.

The sensitivity and specificity of the PCR assay were 97.4% and 99.9%, respectively, and the positive and negative predictive values were 90.2% and 99.9%, respectively.

Of the 16 infants who were positive on one of the PCR assays, but not on rapid culture, 13 underwent follow-up testing of saliva and urine samples; only three actually had a cytomegalovirus infection.

"Although false-positive saliva PCR results could lead to unwarranted parental anxiety and additional testing in infants to confirm or rule out congenital cytomegalovirus infection, the overall frequency of false-positive results for both liquid-saliva and dried-saliva PCR assays was less than 0.03%," they wrote. Those false-positives may have been the result of cytomegalovirus-containing maternal secretions in the infants' mouths, according to the researchers.

"Nevertheless," they added, "when saliva PCR assay is used to screen newborns, a positive screening result should be confirmed within the first three weeks of age to avoid false-positive screening results."
Although the dried-saliva PCR assay failed to identify two infants who had the infection according to the standard rapid culture -- and the liquid-saliva PCR assay did not miss any -- the researchers suggested that using dried saliva may be preferable for screening.

"The simplified procedures for specimen collection, storage, and transport, combined with the high sensitivity, support dried-saliva PCR assay as a reasonable approach to cytomegalovirus screening in newborns," they wrote.

They acknowledged that the study was limited in that the infants who were found negative on initial testing were not enrolled in follow-up testing to confirm the absence of the infection.

Action Points:

• Explain that PCR testing of liquid or dried saliva was able to identify newborns with congenital cytomegalovirus infection with high sensitivity and specificity.
• Note that congenital cytomegalovirus infection is usually asymptomatic but can cause hearing loss; currently newborns are not screened for this infection.

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Periodic table gains two elements

Chemistry officials have confirmed the creation of two new elements - so now names will be given to elements 114 and 116. By John Roach

The periodic table has two new heavyweights, elements 114 and 116, according to a committee of  international chemists and physicists. The elements are fleeting — they are created by bombarding lighter elements together and exist for less than a second before undergoing radioactive decay. Such a short lifespan means that we can't say much about them other than they really do exist.

"The lifetimes of these things have to be reasonably long so you can study the chemistry — meaning, pushing a minute," Paul Karol  of Carnegie Mellon University in Pittsburgh, who chaired the committee that approved the new elements, told New Scientist.

The evidence for element's existence has been mounting for more than a decade. In 1999, for example, Russian scientists with the Joint Institute for Nuclear Research bombarded plutonium-244 with calcium-48 to produce a single atom of 114, which has an atomic weight of 289.

Further collaboration between Russian and U.S. scientists at the Lawrence Livermore National Laboratory resulted in papers published in 2004 and 2006 on the creation of the elements 114, 116, and the yet-to-be-approved 118.

To create 116, the researchers smashed together curium atoms, which have 96 protons in their nucleui, with calcium nuclei, which have 20 protons. This lasted a few milliseconds before decaying into 114, which in turn decayed into copernicum, element 112.

These papers served as the basis for review by the International Union of Pure and Applied Chemistry, which made the formal announcement of the new elements on June 1 with the publication of a paper in Pure Applied Chemistry.

The elements currently go by the placeholder names ununquadium and unuhexium, which by IUPAC convention are derived from the digits 114 and 116. The Russian discovery team at JINR has proposed flerovium for 114, after Soviet element finder Georgy Flyorov, and muscovium for 116, after Russia's Moscow region, according to Wired.

The committee also reviewed claims associated with elements 113, 115, and 118, but found they are not yet conclusive and thus do not meet the criteria for discovery. For more information on how the elements were discovered and the review process, check out the video above from the University of Nottingham's Periodic Table of Videos series.

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Protein folding made easy

Protein folding has nothing to do with laundry. It is, in fact, one of the central questions in biochemistry. Protein folding is the continual and universal process whereby the long, coiled strings of amino acids that make up proteins in all living things fold into more complex three-dimensional structures. By understanding how proteins fold, and what structures they are likely to assume in their final form, researchers are then able to move closer to predicting their function.

This is important because incorrectly folded proteins in humans result in such devastating diseases as Alzheimer's, Parkinson's, Huntington's, emphysema and cystic fibrosis. Developing better modelling techniques for protein folding is crucial to creating more effective pharmaceutical treatments for these and other diseases.

Computational methods of modeling protein folding have existed for a couple of decades. But what McGill researcher Jérôme Waldispühl of the McGill Centre for Bioinformatics has done, working with collaborators from MIT, is to develop algorithms that can work from a laptop computer to examine a protein's fundamental chemical properties and then scan a number of possible protein shapes before predicting the final form that the protein is likely to take.

The results have been impressive. Whereas classical techniques for predicting protein folding pathways required hundreds of thousands of CPU hours to compute the folding dynamics of 40 amino acids proteins, the program folder implemented by Solomon Shenker – a former McGill under-graduate student now at Cornell – has been able to predict correctly in 10 minutes on a single laptop, a coarse-grained representation of the folding pathways of a protein with 60 amino acids.

Waldispühl and his students continue to work on their algorithm to improve its success rate at predicting protein folding with broader categories of proteins including some that are important in DNA-binding. The research was recently presented at the 15th Annual International Conference in Research in Computational Molecular Biology (RECOMB 2011).

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Ninhydrin test or Ninhydrin reagent

Ninhydrin (2,2-Dihydroxyindane-1,3-dione) is a chemical used to detect ammonia or primary and secondary amines. When reacting with these free amines, a deep blue or purple color known as Ruhemann's purple is produced. Ninhydrin is most commonly used to detect fingerprints, as the terminal amines or lysine residues in peptides and proteins sloughed off in fingerprints react with ninhydrin.

Ninhydrin can also be used to monitor deprotection in solid phase peptide synthesis (Kaiser Test). The chain is linked via its C-terminus to the solid support, with the N-terminus extending off it. When that nitrogen is deprotected, a ninhydrin test yields blue. Amino-acid residues are attached with their N-terminus protected, so if the next residue has been successfully coupled onto the chain, the test gives a colorless or yellow result.

Ninhydrin is also used in amino acid analysis of proteins: Most of the amino acids are hydrolyzed and reacted with ninhydrin except proline; Also, certain amino acid chains are degraded. Therefore, separate analysis is required for identifying such amino acids that either react differently or don't react at all with ninhydrin. The rest of the amino acids are then quantified colorimetrically after separation by chromatography.

A solution suspected of containing the ammonium ion can be tested by ninhydrin by dotting it onto a solid support (such as silica gel); treatment with ninhydrin should result in a dramatic purple color if the solution contains this species. In the analysis of a chemical reaction by thin layer chromatography (TLC), the reagent can also be used. It will detect, on the TLC plate, virtually all amines, carbamates and also, after vigorous heating, amides.

When ninhydrin reacts with amino acids, the reaction also releases CO2. The carbon in this CO2 originates from the carboxyl carbon of the amino acid. This reaction has been used to release the carboxyl carbons of bone collagen from ancient bones for stable isotope analysis in order to help reconstruct the palaeodiet of cave bears.

A ninhydrin solution is commonly used by forensic investigators in the analysis of latent fingerprints on porous surfaces such as paper. Amino acid containing fingermarks, formed by minute sweat secretions which gather on the finger's unique ridges, are treated with the ninhydrin solution which turns the amino acid finger ridge patterns purple and therefore visible.

The carbon atom of a carbonyl bears a partial positive charge enhanced by neighboring electron withdrawing groups like carbonyl itself. So the central carbon of a 1,2,3-tricarbonyl compound is much more electrophilic than one in a simple ketone. Thus indane-1,2,3-trione reacts readily with nucleophiles, including water. Whereas for most carbonyl compounds, a carbonyl form is more stable than a product of water addition (hydrate), ninhydrin forms a stable hydrate of the central carbon because of the destabilizing effect of the adjacent carbonyl groups.

Note that in order to generate the ninhydrin chromophore, the amine is condensed with a molecule of ninhydrin to give a Schiff base. Thus only ammonia and primary amines can proceed past this step. At this step, there must also be an alpha proton (H* in the diagram) for Schiff base transfer, so an amine adjacent to a tertiary carbon cannot be detected by the ninhydrin test. The reaction of ninhydrin with secondary amines gives an iminium salt, which is also coloured, and this is generally yellow-orange in color.

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Polysaccharides are carbohydrates

Polysaccharides are carbohydrates formed by more than 9 monosaccharides linked by glycosidic bonds.

When they are formed by the same kind of monosaccharides, they are called homopolysaccharides, like starch, glycogen and cellulose, formed each of them by hundreds of molecules of glucose linked by glycosidic linkages.

If the polysaccharides molecules are formed by different kinds of monosaccharides, they are considered heteropolysaccharides. Hyaluronic acid, formed by thousands of alternative units of N-acetyl glucosamine and glucuronic acid, is an example of heteropolysaccharide.  

HOMOPOLYSACCHARIDES:

Cellulose

Cellulose is a linear polymer of D-glucose residues bonded by b(1, 4)-O-glycosidic linkages. It is the most abundant carbohydrate in nature.

It is formed by glucose units, linked by Beta-1, 4 O-glycosidic linkages. We can say then that, if we consider the kind of linkage, the repeating unit in cellulose is cellobiose, the disaccharide formed by two molecules of glucose linked by Beta-D-O glycosidic bonds, (that is why some text books say that the monomer in cellulose is cellobiose).

The long fibers of cellulose are held together by intermolecular hydrogen bonds. Hydrogen bonding continues in the same plane with other chains as well as in planes above and below this plane to form strong, fibrous bundles. It made cellulose very appropriate for its structural function in plants

Since cellulose is formed by glucose molecules, it can be a source of energy for certain species. The lack in human beings of appropriate enzymes for digesting cellulose make this polysaccharide unsuitable for human nutrition (Have you though about how hunger in the world could disappear if we had enzymes for digesting cellulose?).

Starch:

Starch is the second most abundant carbohydrate in nature.

The biological functions include, in plants, the main way of storage of sugar, and consequently, of energetic sources; in humans, the first supply of glucose on diet (Answer to C-O7)

Starch is not really a molecule, but a grain formed by two different kinds of molecules: Amylose and Amylopectin

Amylose

Amylose is a linear molecule formed by glucose units linked by alpha-1, 4 O glycosidic linkages. Taking in account the kind of linkage we can say that the repeating unit in amylose is maltose. (It explains that some books indicate that the monomeric unit in amylose is maltose).

Amylose molecule is helicoidal

Amylopectin

Amylopectin is the second type of molecule that forms starch. It is a branched molecule, formed also by glucose. Amylopectin contains D-glucose residues bonded together by a(1, 4)-O-glycosidic linkages with branching through a(1 6)-O-glycosidic linkages.

The disaccharides that can be obtained from the digestion of amylopectin are maltose and isomaltose.

Amylopectin shows a branch each 24-30 units of glucose,

Glycogen:

The structure of glycogen is very similar to amylopectin but more branched, with one branch every 8 to 12 glucose unit

Glycogen is the way in which glucose is stored in animals. Glycogen is stored mainly in liver (to release glucose to blood when necessary) and in muscle, where it is used as a reserve of energy for muscular contraction (Answer to C-o8)

HETEROPOLYSACCHARIDES

Heteropolysaccarides contain two or more different kind of monosaccharides. Usually they provide extracellular support for organisms of all kingdoms: the bacteria cell envelope, or the matrix that holds individual cells together in animal tissues, and provides protection, shape and support to cells, tissues and organs.

Heteropolysaccharides provide extracellular support to very different organisms, from bacteria to humans; together with fibrous proteins, like collagen, elastin, fibronectin, laminin and others, heteropolysaccharides are the most important components of the extracellular matrix.  Hyaluronic acid, condroitin sulfates and dermatan sulfates are important heteropolysaccharides in the extracellular matrix. These heteropolysaccharides usually are formed by the repetition of a disaccharide unit of an aminosugar and an acid sugar. 

A typical example

Other common constituents are sulfate groups linked to certain monosaccharides. Usually heteropolysaccharides are associated with proteins forming proteoglycans, glycosaminoglycans or mucopolysaccharides (since they are abundant in mucous secretions). As a group, they perform diverse functions: structural, water metabolism regulation (as a reservoir of water), cellular cement, biological sieve, biological lubricant, docking sites for growth factors, among other functions.

Established specific functions of some glycosaminoglycans are:

Hyaluronic Acid (Hyaluronate): It is a lubricant in the synovial fluid of joints,

give consistency to vitreous humor, contributes to tensile strength and elasticity of cartilages and tendons (Answer to C-O6)

Chondroitin Sulfates: contributes to tensile strength and elasticity of cartilages, tendons, ligaments and walls of aorta.

Dermatan sulfate (former chondroitin sulfate B) is found mainly in skin, but also is in vessels, heart, lungs. It may be related to coagulation and vascular diseases and other conditions.

Keratan sulfate: Present in cornea, cartilage bone and a variety of other structures as nails and hair.

Heparin:

It is a potent natural anticoagulant produced in the Mast Cells that causes antithrombin bind to thrombin and produce inhibition of blood coagulation.

Glycosaminoglycans are synthesized in the ER and Golgi. They are degraded by lysosomal hydrolases. A deficiency of one of the hydrolases results in a mucopolysaccharidosis. These are hereditary disorders in which glycosaminoglycans accumulate in tissues, causing symptoms such as skeletal and extracellular matrix deformities, and mental retardation.

Examples of these genetic diseases are Hunter and Hurler syndromes.

These diseases, caused by different enzyme deficits, are characterized by physical deformities, mental retardation and disturbances in the degradation of heparan sulfate and dermatan sulfate.

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