Chromosomes, Genes and Proteins

Chapter 1: Chromosomes

Chromosomes are long, thin strands of DNA that are located in the nucleus of a cell.
All chromosomes are made of two main parts which are DNA and protein compounds.
There are 23 pairs of chromosomes in a human cell; one from the mother and one pair from the father.
Variations in chromosomes and genetic information can lead to different features or genetic disorders.

Chapter 2: Genes

Genes are sections of DNA found on a chromosome.
Each gene contains the instructions for the development of a particular characteristic.
Genes control the characteristics of an organism.
Each gene codes for a specific sequence of amino acids which form a specific protein.
Genes can be dominant or recessive, where the dominant ones mask the effect of the recessive ones.

Chapter 3: Proteins

Proteins are a vital building block for cells and directly affect the structure and function of cells.
They are composed of one or more chains of amino acids which are determined by the DNA sequence of a gene.
Proteins play a massively crucial role in nearly all biological processes.
Some proteins act as enzymes and control the rate of metabolic reaction.
Changes or mutations in the sequence of amino acids can result in faulty proteins which cause genetic diseases.

Chapter 4: DNA

DNA stands for deoxyribonucleic acid.
DNA is a molecule that carries the genetic instructions for growth, development, functioning and reproduction of all known organisms.
DNA molecules are double-stranded and shaped like a double helix, with bases paired in the middle.
The order of the bases determines the order of the amino acids in a protein, thereby determining its function.
Mutations occur when there are changes in the base pair sequence in DNA.