You and your genes Flashcards
What carries the instructions for the proteins that are needed to make your cells to work?
Genes
What chemical makes up a gene?
DNA (DeoxyriboNucleic Acid)
What are the coils of DNA called?
Chromosones
What is the shape of a chromosome?
Double helix
How do you tell the sex of a chromosome?
Take off its genes. In mammals, the y chromosome makes male, XX is female.
Where would you find the chromosomes?
In the cell nucleus
How are genes coded?
The order of the bases determines the order of the amino acids in the protein
What two groups of proteins are coded on genes?
Functional proteins and structural proteins.
What is a functional protein?
A protein needed to make the body function, eg enzymes, hormones, antibodies
What is a structural protein?
A protein that is part of the structure of the body, eg skin (keratin) or collagen (found in skin, ligaments)
What was the project to map the human genes called?
The human genome project
What is the complete set of genes of an organism called?
The genome
What controls the characteristics of an organism?
Genes, environment, or a combination.
What are the ethical considerations of the human genome project?
Some companies want to patent genes. They would then “own” genes and could charge other scientists to investigate those genes. This would restrict research.
What is the consequences of differences in genes?
Variations within the species.
How many genes control each characteristic?
It can be one, or many.
If there are many genes controlling a characteristic how is the characteristic expressed within the population?
There will be continuous variation within the population, eg height.
What is the genotype?
The genes of an organism, usually expressed as two letters, eg Ee
What is the phenotype?
The observable physical characteristic of the organism
What is the phenotype affected by?
Genes and environment.
Why are studies on identical twins so valuable?
It enables research into the effects of the environment on an organism.
How many pairs of chromosomes does the human have?
23
How many chromosomes does the human have?
46
How many chromosomes in a human sex cell?
23
What do a sperm cell and an egg form when they combine?
A zygote
What is the process of the joining of egg and sperm?
fertilisation
How many chromosomes in the human zygote?
46
What are changes to DNA called?
Mutation