3.24c Mitosis 3

• We look down the microscope we would be unable to absorb the chromosomes. During the interphase the DNA replication occurs.
• The nucleus break down in the phase of the prophase the chromosomes become visible.
• The nucleus is gone. Insides the cell a network of protein molecules known as a "Spindle"/ fibres. Extend from one pole of the cell to another, which is known as late prophase.
• The metaphase is showing one pair of chromotids. The chromosomes are in the middle. The anaphase the fibre shortens, pulling each direction and the pair of chromotids moving apart to the poles and separate pair of chromotids later.
• Telophase is when the nucleus began to form. We see two set of chromosomes in each end. Cytokinesis is when there are new copy of chromosomes.

3.24b Mitosis 2

• Copying chromosomes are DNA replication.
• The two copy are held together by the centromere.
• We would called 'Pair of chromatids".
• The process of DNA replication takes place inside the nucleus while nucleus is still intact we can't see the process.
• This is known as "Interphase".

3.24a Mitosis 1

• The outline, we will begin with a cell. The diploid number is known as chromosome number.
• For example, human is 2n= 46 and cat is 2n=38.
• The cell will divide into two cells and each of the cells we will find diploid nucleus, we say these cell are identical or daughter cells.
• There are two points about the cell:

1. Same  number if chromosomes.
2. Same sex of chromosomes.

•  We would find same version in each cells cause there are copies of chromosomes.

3.16 DNA and Genetic information

• The chromosome are likely to contain 1000's of genes. We would expand the geneloci.
• We would find double helix when we expand, the would appear to be parallel.
• Then we expand again, we would see the two sides that are holding which is known as "sugar-phosphate backbone". There are no chemical it.
• In the base there are 4 letters that are stand for A (adenine) that pairs with T (thvmine) and another pair is C (cvtosine) that pairs with G (guanine).
• The order of the bases we call the gene. So, the gene is  the order of the bases of 1 side of double helix.

* What is the other side of the double helix be if the other side is "gene"?

3.15 Genes

• The section is called "Gene" this gene carry information which form characteristic of the organism. E.g. blood group, petal colour.
• There is an important thing that you need to remember is that the gene is located in the nucleus.
• The information is past through the cytoplasm.
• The cytoplasm is the protein.
• The information flow from gene to the protein.

* Why does the gene located in the nucleus?

3.14 Chromosomes

• A typical cell has a nucleus and we would find a chromosome.
• The chromosome is compose of a molecule of DNA.
• This form a shape "double helix"  section of the molecule are called "gene". Each gene carry the information for a construction of protein.
• The protein gives us characteristic of the gene e.g. blood.
• Operated in pairs are homologous pairs.

* Why does it need to go in pairs?

3.1 Sexual and Asexual reproduction

• Sexual Reproduction are sex from male and female, Asexual Reproduction doesn't need the sexes.
• Sexual Reproduction produces cells called "Gametes" which are sperm cells for male and egg for female and Asexual Reproduction doesn't produce Gametes.
• In Sexual Reproduction has Meisosis that are half of the chromosones in the Gametes cells. In human for total number of chromosones in adult is 46 per cell and in Gametes is 23 per cell. In Asexual Reproduction there is Mitosis/Binary fission in bacterial cell.
• Fertilisation fuse would be found in the Sexual Reproduction. There are no fertilisation found in Asexual Reproduction.
• In Sexual Reproduction variation is broad and in Asexual Reproduction show small amount of variation but the are identical which is "clone".