5. EVOLUTION

Question 1

Explain the process of evolution.

Answer 1

• Cumulative change in the heritable characteristics of a species
• more offspring than the environment can support
• competition for resources
• variation existing in a popluation necessary for Evolution
• variation comes from random orientation of chromosomes, crossing over, random fertilisation
• better adapted individuals will survive and pass on their traits to offspring
• change in frequancy of allelles over time
• gradualism/ punctuated equilibrium

Question 2

Classify one animal species from domain to species level.

Answer 2

Domain: Eukaryote
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primate
Family: Hominidae
Genus: Homo
Species: sapiens

Question 3

Classify one plant species from domain to species.

Answer 3

Domain: Eukaryote
Kingdom: Plantae
Phylum: Angiospermophyta
Class: Magnoliopsida
Order: Rosales
Family: Rosacae
Genus: Fragaria
Species: ananassa

Question 4

Distinguish Archaea and Eubacteria

Answer 4

Archaea: DNA associated with histones, has introns, no glycoprotein on cell wall, cell wall with glycerol-ether
Eubacteria: naked DNA, no introns, glycoprotein on cell wall, glycerol-ester

Question 5

Explain how cladistics can be used to investigate evolutionary relationships.

Answer 5

• cladistics used DNA base sequence or aminoacid sequence as evidence for evolutionary relatedness to a common ancestor
• the more differences there are between species the longer ago the species have diverged
• less differences means closer evolutionary relationship