Origins of Genetic Variation

Question 1

What are the types of gene mutations?

Answer 1

-Deletion
-Insertion
-Substitution

Question 2

What are the types of chromosomal mutations?

Answer 2

-Crossing over
-Independent assortment
-Random fertilisation

Question 3

What is the law of segregation?

Answer 3

One allele is inherited from each parent

Question 4

What is the law of independent assortment?

Answer 4

Different traits are inherited independently of each other

Question 5

Why are flies, bacteria, fungi and pea plants used in experiments?

Answer 5

-Produce large amounts of offspring so results are relevant
-Short life cycle so mutations can be seen quickly
-Easy and cheap to raise

Question 6

What is homogametic?

Answer 6

Female has two X large chromosomes so all of her eggs contain an X chromosome

Question 7

What is hetrogametic?

Answer 7

-Male has one X chromosome and a smaller Y chromosome
-One half of the sperm cell will contain an X chromosome and the other half will contain a Y chromosome

Question 8

What is dihybrid inheritance?

Answer 8

Two characteristics are determined by two different genes on different chromosomes

Question 9

What is autosomal linkage?

Answer 9

When two or more genes that are being inherited are located on the same autosome (a non sex chromosome)
E.g.
-Genes on same chromosome
-Genes are linked

Question 10

What is the equation for allele frequency?

Answer 10

p + q = 1
-p = frequency of dominant allele
-q = frequency of recessive allele

Question 11

What is the equation for genotype frequency?

Answer 11

p2 + 2pq + q2 = 1
-p2 = individuals who are homozygous dominant
-2pq = individuals who are hetrozygous
-q2 = individuals who are homozygous recessive