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What is Cell division and its types?

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Cell Division - Cell division is a process in which the single cell divide or multiply into two or more identical cells. It play important role in growth, reproduction and repair. There are three types of cell division-  1) Amitosis 2) Mitosis 3) Meiosis 1) Amitosis - is the process in which the cell is directly divide into two daughter cell without any formation of spindle and appearance of chromosomes. The nucleus present inside the cell elongates and develops a constriction round its middle. This constriction gradually deepens and finally cuts the nucleus into two daughter cells. Example - Paramecium divide by amitosis.   2) Mitosis- is the process in which two identical daughter cell produced by a single parent cell by karyo-kinesis, cytokinesis and cell separation. The daughter cells carry same amount of DNA, same amount and kind of Chromosomes and same hereditary instruction from parent cell so that this division also known as equational division. It occur in all ...

What is MITOSIS?

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MITOSIS is the one of cell division method. It is the process in which the parent cell divide into two identical daughter cells. Both daughter cells having nucleus with same amount of DNA, chromosomes and same hereditary instructions from parent cell. This division called equational division. It takes place in somatic cells of animals. So that it also known as somatic division.  In 1875 Eduard Strasburger   firstly described the mitosis in plant cells. After that, In 1879 Walther Flemming described the mitosis in animal cells.  Mechanism of Mitosis- The parent cell divide into two equal daughter cells by Karyo-kinesis, Cytokinesis and Cell separation. Karyo-kinesis is the division of  nucleus. Cytokinesis is the division of  cytoplasm. The duration of Mitosis is from 30 minutes to 3 hours.  A. Karyo-kinesis  is the division of cell nucleus. This process divide into four stages-  1) Prophase 2) Metaphase 3) Anaphase  4) Telophase 1) Prophas...

Difference between Osmosis and Diffusion?

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                                                                                                                                       Osmosis - 1) It is the movement of solvent from higher water concentration to lower water concentration . 2) It take place through semi permeable membrane. 3) Osmosis occurs in liquid medium only.    4) Only the solvent molecules move from one place to another. 5) It does not equalize the concentration of solvent molecules. 6) Osmosis can be stopped and reversed by applying external pressure. 7) Example - Sugar molecules are solute and the water molecules are solvent. This example shows the movement of water ...

BLOOD GROUP?

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Blood is a circulating life sustaining fluid. It provides oxygen and nutrients for cells, tissue and organs. It keeps body warm 37degreeC. In some clinical cases we need to do blood transfusion. The blood transfusion is done on the basis of BLOOD GROUP.  Blood are four types A, B, AB, O these are known as ABO blood group . The types of blood group is depend upon the presence and absence of antigen and antibody on Red blood cells. In 1900 Karl Landsteiner recognized these types of blood group in human being. He observed that ABO blood group are determined by gene I. This gene I have three alleles IA, IB and IO.  Each blood group has antigen on the surface of red blood cell and opposing antibody in plasma.  The presence of antigen and anti-antibody accordingly-  1) Blood group A - In this the A antigen is present on the surface of red blood cell and Anti-B antibody present in plasma 2) Blood Group B - In this the B antigen present on the surface of red blood cell and ...

How molecules transport across the Cell Membrane?

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  Cell membrane is made up of phospholipid bilayer. It provide a path for material or molecule to go inside the cell or outside the cell. Cell membrane is a Semipermeable membrane. That ensures only useful material go inside the cytoplasm. There are two main processes for transporting of material inside or outside the cell.    I) Physical process   II) Biological process   I) Physical Process -   in this process the molecules are move across the cell membrane by diffusion, osmosis, filtration and dialysis.   i) Diffusion - is the process in which the solute molecules move from higher concentration to the lower concentration. This process does not require semi- permeable membrane. Diffusion molecules may be solid, liquid or gas. It can take place in any medium.    Example - Take a beaker and fill it with water. Now place a cube of sugar in the beaker . T he concentration of solute is higher than the concentration of solvent. S...