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Cellular organization

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Living things are highly organized and structured, following a hierarchy that can be examined on a scale from small to large. The atom is the smallest and most fundamental unit of matter.Atoms form molecules Many molecules that are biologically important are macromolecules,   An example of a macromolecule is deoxyribonucleic acid (DNA), which contains the instructions for the structure and functioning of all living organisms. Macromolecules can form aggregates within a cell that are surrounded by membranes; these are called organelles. Organelles are small structures that exist within cells. Examples of these include: mitochondria and chloroplasts, which carry out indispensable functions. Mitochondria produce energy to power the cell while chloroplasts enable green plants to utilize the energy in sunlight to make sugars. All living things are made of cells, and the cell itself is the smallest fundamental unit of structure and function in living organisms. cells combine to make tissues,
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Retrotransposons and its type

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Define retrotransposons with example. Class 1 transposons also known as retrotransposons move through the active RNA intermediaries. In other words, class 1 Te1 do not encode transposase, rather they produce RNA transcripts and then relay upon reverse transcriptase enzymes to reverse transcribe the RNA sequence back into which is then inserted into target site. There are two types of class 1 Te s 1) LTR ( long terminal repeat): LTR retrotransposons are characterized by the presence of long terminal repeats on both ends of LTR retrotransposons and DNA transposons are only ancient genomic relics and are not capable of jumping. Eg: Human endogenous retroviruses and various Ty elements S cerenisione. 2) Non LTR retrotransposons:  Non LTR Te s, lack the repeats and include both autonomous and non-autonomous members. Autonomous Non LTR retrotransposons include LINES (long interspersed nuclear elements). In mammals non LTR retrotransposons are the most common type of mobile elements. Line 1 o
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PROKARYOTIC TRANSPOSONS

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Define Prokaryotic transposons with diagram. Although the presence of transposons was predicted in Eukaryotes but first observation at molecular level was done in bacteria. Which is a Prokaryote. Bacterial transposable elements are of following types: A) Insertion sequence or I s elements: They are the transposable sequence which can insert at different sites in the bacterial chromosomes.  I s  elements contains ITRs (inverted terminal repeats) these were first observed in E.coli. The term ITRs implies that the sequence at 5' end of one strand is identical to the sequence at 5' end of the other strand but they run in opposite direction. B) Prokaryotic transposon element: These are also called composite transposons and are shown by symbol "Tn".  These are large transposons which are formed by capturing of an immobile DNA sequence within two insertion sequences thus enabling it to more. Eg:  Tn1, Tn5, Tn9, Tn10, etc..
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Cdc 25A

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M phase inducer phosphatase 1 also know as dual specificity phosphatase CDC 25A is a protein that in humans encoded by cell division cycle 25 homolog A (Cdc 25A)  gene. It is a member of the Cdc 25 family of dual specificity phosphatases. Cdc 25A is required for progression from G1 to the S phase of the cell cycle.  Plays role in later cell cycle events. In particular it is stabalised in metaphase cells and is degraded upon metaphase exit  akin to  cyclin B. It is competent to activate G1/S cyclin dependent kinases Cdk 4 and Cdk 2 by removing inhibitory phosphatase groups from adjacent tyrosine and theronine residues.  It can also activate Cdc 2 (cdk 1) the principal mitotic cdk. Cdc 25A is specifically degraded in response to DNA damage, resulting in cell cycle arrest. 
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GOLGI BODY

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Golgi body or Golgi apparatus is an organelle in eukaryotic organisms that move molecule from endopasamic reticulum to their destinations. It was founded by or discovered by Camillo Golgi. The component of golgi body are: 1. Cisternae  2. Tubule 3. Vesicles  4. Golgi vacuole (lysosomes) STRUCTURE: The image below shows the structure of Golgi apparatus. The cis face of the organelle is closest to the endoplasmic reticulum (ER). The trans face is the side farthest to the nucleus, which secrets vesicles to various parts of the cell.  There are a number of lumens and cisternae through which the products flow. These appear as a series of flattened sacs stack on each other, much like the endoplasmic reticulum.  LOCATION: The Golgi apparatus is situated in between the endoplasmic reticulum (ER) and cell membrane. Most often the Golgi appears to be an extension of endoplasmic reticulum which is slightly smaller and smoother in appearance. FUNCTION: 1. Packages products into vesicles for transp
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EFA- Omega-3

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It us correctly said "what we eat, is what we are." This fits best in terms of fatty acids. Though some are formed in animals, predominantly in liver, adipose tissue and mammary glands (during lactation) through it from carbohydrates, some are also found in eatables.  Our body has a great demand of fatty acids. Few important terms of fatty acids like omega-3 and omega-6 are of immense importance for our body. Today, I would be discussing about fatty acids and essential fatty acids. Which play a very important role in our body functioning. So let's start. Fatty acid is a carboxylic acid with a long aliphatic chain, which is either saturated or unsaturated. Most naturally occuring fatty acids have unbranched chain of even number of carbon atoms, from 4-28. Fatty acids are usually not found in organisms, but instead as three main classes of esters: triglycerides, phospholipids and cholesteryl esters. In any of these forms, fatty acids are both important dietary sources of fu
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STERILIZATION AND ITS CHEMICAL METHODS.

In last post we discussed about sterilization and its physical methods. In this post we will discuss about sterilization and its chemical methods in the most precise way. By this far we know that sterilization can be defined as the process of killing all microorganisms (including spores) on or in a material or object.  We also know that heating is the most common and reliable method for sterilization.  Here are some chemical methods of sterilization: 1) Gases: Types used in sterilization: a) Ethylene oxide b) Formaldehyde gas: This is widely employed for fumigation of OT and other rooms. c) Betapropiolactone:  -having rapid bactericidal activity but carcinogenic. - capable of killing all microorganisms and is very active against viruses. 2) Surface active agents:  Substances that alter the energy relationship at interfaces, producing a reduction Of surface or interfacial tension is called surface active agents. They are widely used as wetting agents, emulsifiers and detergents. These a
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