10 Science:
Genetics Terms and Definitions
Match the following terms with the definitions listed below:
, Gamete,,
Pedigree, Trait,
Gene
A section of DNA that codes for a protein and determines a trait.
allele
An alternative form of a gene. Eg the allele codes for eye colour,
the gene is blue eyes.
chromosomes
A length of DNA found inside the nucleus of a cell.
DNA
A long molecule of information that organises life and can be passed on to the
next generation.
Trait that will show up in an organism’s phenotype if the gene is present.
dominant
recessive
phenotype
Trait that will only show up if the organism inherits two of the same alleles.
Will not show up if a dominant allele is present.
The physical expression of a gene.
genotype
The genetic make up of an organism.
variation
Changes from the original feature. Differences in a population.
homozygous
Two identical alleles for a particular trait, eg HH, hh
heterozygous
Two different alleles for a particular trait, eg Hh.
punnett square
A diagram that shows all the possible outcomes of a genetic cross between
two parents.
A specific characteristic that varies from one individual to another.
trait
karyotype
pedigree
gamete
A chromosome map that shows the order of chromosomes of an individual.
Can be used to show genetic disease.
A map showing a specific trait through several generations of one family
A sex cell, a sperm or ovule (egg).