selective breeding Flashcards
genome
the sum total of genes in an organism
phenotype
the observable characteristics of an organism. depends on a genotype and environment
genotype
the alleles present in an organism
locus
position on a homologous chromosome of a particular gene
homologous chromosome
a pair of chromosomes that have the same gene loci but not necessarily the same allele
allele
alternative form of a gene
gene
length of DNA that codes for a polypeptide
gene pool
Total number of all alleles of all genes of al individuals within a particular population at a given time
population
all the organisms of one species in a habitat
species
A group of similar organisms that can interbreed to produce fertile offspring
dominant allele
the allele which exerts an affect on the phentoype of the heterozygote
recessive allele
The allele which has no effect on the phenotype of the heterozygote
co-dominant allele
When both alleles exert an effect on the phenotype of the heterozygote
gamete
a sex cell e.g. sperm or ovum
zygote
the fertilised female gamete
homozygous
A genotype in which the 2 alleles of a gene are the same
heterozygous
A genotype in which the 2 alleles of a gene are different
haploid
Cells containing one full set of chromosomes
diploid
Cells containing two full set of chromosomes
what is variation?
difference that exists between individuals.
variation between species and within species
variation between species
Different species have different genes which results in different phenotypes
variation with A species
Individuals of the same species have the same genes but different alleles (version of gene)
what is genetic diversity
Genetic diversity is the “total number of different alleles in a population”
what causes variation in a species?
genetic and environmental factors