Continuity of Species | Part 1

Question 1

Define

Allele

Answer 1

Variants of a gene, e.g. eye colour.

Question 2

Define

Gene Pool

Answer 2

Number and type of genes within a population.

Question 3

Comment on the relationship between:

Offspring Diversity & Gene Pool

Answer 3

↑ Offspring diversity, ↑ Gene pool

Question 4

Explain why:

A low genetic diversity in a population may cause all of its inhabitants to die.

Answer 4

Limited genetic variation — less chance for a ‘fit’ gene to be present.

Question 5

Define

Genetic Drift

Answer 5

The random changes in a population’s gene pool and allele frequencies from generation to generation

(i.e. drift from the founding generation)

Question 6

Explain why:

A small population size leads to very inconsistent generation-to-generation allele frequencies.

Answer 6

Random changes in

Question 7

Divergent Evolution

Answer 7

Characteristics that come from the same organism changing over time due to selection pressures

Question 8

Convergent Evolution

Answer 8

Genetically dissimilar organisms adopt similar characteristics due to environment

Question 9

Evidence for Evolution

Answer 9

• Fossils
• Comparative Anatomy – Homologous and Analogous Structures
• Embryology

Question 10

Homologous Structures

Answer 10

These are structures within different organisms which are similar in shape, but not necessarily function.

(e.g. dolphin are mammal, shark are fish, both have fins)

Question 11

Analogous Structures

Answer 11

Similar structures, which are not genetically linked. Sometimes these similar structures have similar functions.

(e.g. birds and bats’ wings)

Question 12

Define

Allopatric Speciation

Answer 12

When biological populations of the same species become isolated from each other to an extent that prevents or interferes with interbreeding even when the isolation barrier is removed.

Since they cannot interbreed, the two populations are now species

Question 13

Types of Fossils

Answer 13

• Bones
• Coprolites
• Whole Body