Basic Mendelism

Question 1

Basic cross ratio

Answer 1

3:1

Question 2

Locus

Answer 2

Chromosomal location of genetic instruction

Question 3

Allele

Answer 3

Alternative forms at particular locus

Question 4

Phenotype

Answer 4

Physical appearance of individual with particular genotype

Question 5

Genotype

Answer 5

Genetic constitution that underlies phenotype

Question 6

Mendel’s 1st Law

Answer 6

(Law of segregation)

Two members of a gene pair segregate into separate gametes

Question 7

Dominant inheritance

Answer 7

Unaffected parents = unaffected children

In families with affected parent around 1/2 children are affected

Question 8

Examples of dominant inheritance

Answer 8

Hapsburg Lip in Philip IV Spain

Huntington’s Disease

Question 9

Recessive Inheritance

Answer 9

Unaffected parents can have affected children

In an affected family around 1/4 children affected

Question 10

Example of recessive inheritance

Answer 10

Cystic Fibrosis carried by 1/25 Europians

Question 11

Genetic counselling

Answer 11

Terminating a pregnancy if it is carrying a certain gene