Inheritance key words

Question 1

Define Co-dominance

Answer 1

• When 2 alleles do not have complete dominance over each other
• Both expressed in phenotype

(3 phenotypes, 2 alleles)

Question 2

Define Multiple alleles

Answer 2

• More than 2 alleles for a gene
  (eg. Blood groups ABO)

Question 3

Define Autosomal linkage

Answer 3

• 2 different genes on the same autosome
• Not X or Y chromosome
• Linked because aren’t separated in meiosis independent segregation

Question 4

Define Epistasis

Answer 4

• 1 gene masks and modifies the expression of another
• alters expected ratio

Question 5

Define Monohybrid

Answer 5

• Crossing one gene
• 3:1 ratio

Question 6

Define phenotype

Answer 6

• expression of genetic constitution
• and its interaction with the environment

Question 7

Define genotype

Answer 7

• genetic constitution of an organism

Question 8

Define Homozygous

Answer 8

• 2 copies of the same allele for a gene

Question 9

Define linkage

Answer 9

When more than 2 genes are located on the same chromosome, they are linked.

Question 10

Define heterozygous

Answer 10

• 2 different alleles for a gene

Question 11

Define sex linkage

Answer 11

• Genes loci located on X or Y chromosome
• in non-homologous region
• Mostly X chromosome as Y is too small

Question 12

Define dominant allele

Answer 12

A version of a gene that is always expressed in phenotype

Question 13

Define recessive allele

Answer 13

Version of a gene that’s not expressed if there is dominant alleles present