Biology Flashcards
What is a phenotype?
A phenotype is the set of observable characteristics of an individual.
The percentage
What is a genotype?
What alleles you have e.g Ee
What is a allele?
An allele is two or more alternative forms of a gene that are usually caused by mutation
Variation:
Members of a population that are different, and genetically based variations can be passed on to offspring.
Inheritance:
Organisms reproduce giving rise to descendant populations
Over production:
For many organisms more offspring are produced than can possibly survive.
Adapted:
Individuals that can compete successfully for environmental resources are selected for.
Selection pressures
Environment change over time and inherited characteristics that suit a particular environment will be selected.
Genetic drift
In small populations shifts in frequency of certain characteristics can occur buy chance
Isolation
When population are geographically isolated and cannot interbreed they may change over time to become different species
What is natural selection
The prices where selection pressures acts on a population in the wild and results in some organisms having more surviving offspring than others.
What are the three main sources of variation in a species?
Mutations
Meiosis
Sexual reproduction
Hetrozygous
Different e.g Hh
Homozygous
The same e.g HH, hh
Dominant
Is capital letter BB
Recessive
The lower case cc
What is mutation?
Mutation is something that causes a change to DNA usually when being copied
Haploid
Having a single set of unpaired chromosomes
Diploid
Containing two complete sets of chromosomes one from each parent
Mitosis
Process in which body cells undergo division to produce daughter cells identical to parent cells from which they came
Gene
Process in which gametes are created the division results in the gamete cells containing only half the normal chromosome number
