Topic 33

Question 1

Polygenic inheritance

Answer 1

refers to those determined by many genes

Question 2

Oligogenic inheritance refers to

Answer 2

refers to those determined by a few genes

Question 3

Pathological traits

Answer 3

abnormalities that cause change in structure or function in the body

Question 4

Threshold traits

Answer 4

A threshold trait is a trait, which is inherited quantitatively, but is expressed qualitatively. Normally a lot of genes form the basis of a threshold trait, which is why it should be treated as a quantitative trait.

expressed in only 2 forms; Single threshold trait, Multiple threshold trait

Question 5

Single threshold trait

Answer 5

mortality, bone breaks, single birth or twin birth

the biological threshold that must be met before a disease(trait) developes

Question 6

Multiple threshold trait

Answer 6

scrapie
mastitis in cattle; blood spots in chicken egg

the biological threshold that must be met before a disease(trait) developes

Question 7

Genetic predisposition

Answer 7

is a genetic characteristic which influences the possible phenotypic development of an individual organism within a species or population under the influence of environmental conditions

genetic discrimination by health insurance companies?

Question 8

Genetic susceptibility

Answer 8

refers to a genetic predisposition to a health problem, which eventually is triggered by a particular environmental and lifestyle factors. E.g. smoking