- Genes, Chromosomes and DNA
- Most cells in your body have a nucleus. this contains all of your genetic material.
- The genetic material in the nucleus is arranged into chromosomes and there is 23 pairs of chromosomes in the human body.
- Each chromosome is one very long molecule of DNA that is coiled up. this is what gives it its shape
- A gene is a short length of a chromosome.
- A gene controls the development of different characteristics eg: hair colour, and how an organism functions
- Genes can exist in different versions. each version gives a different form of a characteristic, like blue eyes or green eyes. the different versions of the same cell are called allels.
- Each gene is a code for making a certain protein.
- Having different versions of proteins means that we end up with different charecteristic
- Some proteins are structural proteins.
- They are part of things like skin, hair, blood and the cytoplasm in our cells. eg: collagen is a structural protein that is found in tendons bones and cartilages
- Other proteins are functional proteins. for example enzymes are proteins that help with digestion by breaking down food molecules.
- An organism genotype is all of the genes it has and a phenotype is the characteristics that the organism displays.
Similar Biology resources: