10.2 and 10.3

Question 1

What is a dihybrid cross?

Answer 1

2 unlinked traits are crossed

Question 1

What is a gene pool?

Answer 1

A gene pool consists of all the genes and their different alleles, present in an interbreeding population

Question 2

What are the 3 different types of selection?

Answer 2

Stabilising selection (it gets narrower)
Directional selection (it shifts)
Disruptive selection (it parts)

Question 3

What are the 3 types of reproductive isolation?

Answer 3

Temporal isolation: different reproductive cycles
Geographical isolation: not in the same place
Behavioral isolation: different courtships

Question 4

What are the 2 types of speciation?

Answer 4

1. Allopatric speciation: different locations
2. Sympatric speciation: same location

Question 5

How can speciation occur by polyploidy?

Answer 5

Meiotic cells fail to undergo cytokinesis & chromosomal number doubles in gametes. Speciation occurs if the offspring is fertil and cannot reproduce with the original ones.

Question 6

In which genus does speciation due to polyploidy occur commonly?

Answer 6

In the genus allium: onion, garlic…

Question 7

What are the 2 different speed types of speciation?

Answer 7

1. Gradualism: gradual accumulation of genetic changes
2. Punctuated Equilibrium: sudden events suddenly reduce populations and resources