Genetics

Question 1

What are dominant genes?

Answer 1

Genes that mask recessive alleles and show through in physical appearance

Question 2

What are recessive genes?

Answer 2

Genes that are masked by dominant genes and only show through if there are two recessive genes

Question 3

What is homozygous?

Answer 3

When both inhereted alleles / genes are the same
E.G. aa or AA

Question 4

What is heterozygous?

Answer 4

When both inherited genes are different
E.G. Aa

Question 5

What is the phenotype?

Answer 5

The physical appearance

Question 6

What is the genotype?

Answer 6

The genes that’re present that make up the animal
E.G. Aa

Question 7

What is the locus?

Answer 7

The specific area on the chromosome where the gene is located

Question 8

What is incomplete dominance?

Answer 8

When neither gene dominates are both are equally expressed - This gives a dilution or a blend.
E.G. Pink flowers = P
White flowers = p
Pp = Pale pink flowers

Question 9

What is co-dominance?

Answer 9

When neither dominates but both are expressed
E.G. P = Pink flowers
p = White flowers
Pp = Stripy pink and white flowers / blooms of both colour

Question 10

What is an allele?

Answer 10

An alternative form of a gene (one of a pair)

Question 11

What is DNA?

Answer 11

• Nucleic acid in the cell that carries the genetic information
• Occurs in a double helix structure

Question 12

What are chromosomes?

Answer 12

Thread-like structure found in the cells nucleus that makes up DNA

Question 13

What is Mendle’s First law?

Answer 13

• Law of segregation
• During gamete formation, two alleles at a gene locus segregate from each other
• each gamete has an equal probability of containing either allele

Question 14

What’s Mendle’s Second Law?

Answer 14

• Law of independent assortment
• Traits are inherited independently of each other
• Created the DiHybrid cross