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Introduction
Cells are the smallest building blocks of life. Within cells there are smaller structures which are called organelles.
All cells have a cell membrane. The following diagrams show the main differences between plant and animal cells:

Structure Purpose
Chromosomes Structures that carry the genes which determine the characteristics.
Cell wall Provides rigidity and strength in plant cells.
Vacuoles Contains water and dissolved materials. This helps to retain the cell shape by increasing or decreasing in size.
Cytoplasm Fills the cell and is a fluid like “jelly”. Most cellular reactions occur here.
Cell Membrane The outer”skin” of the cell. This acts as the edge of the cell.

Chromosomes are found in the nucleus of cells. Chromosomes are small thread-like structures made up of
deoxyribonucleic acid — commonly called DNA. This DNA has a double helix structure linked by base pairs
spaced at regular intervals. The whole chromosome looks like a double spiral ladder. The genes of an organism
are found on the chromosomes. Each gene is a specific length of the chromosome, probably several thousand
base pairs in length. The specific length and sequence of the base pairs determines a particular protein of an
organism, which in turn forms together with other proteins to form a particular feature, e.g. the colour of your
eyes. A human being has over 80 000 genes along the 46 chromosomes found in the nucleus of every cell in
the human body.

Mitosis 
This is cell division that results in the cells having different sets of chromosomes and half the number of chromosomes.  One cell will divide and form 4 new cells called gametes and these cells are the sex cells.

The process is used to produce the sex cells of the eggs and sperm.

Meiosis
This is cell division that results in the cells having different sets of chromosomes and half the number of chromosomes. One cell will divide and form 4 new cells called gametes and these cells are the sex cells.

The process is used to produce the sex cells of the eggs and sperm.