5. Evolution and Biodiversity

Question 1

Causes of genetic variation

Answer 1

Mutations (germline mutation), Meiosis (crossing over - prophase 1, independent assortment - metaphase 1), Sexual Reproduction

Question 2

Classifications of Adaptions

Answer 2

Structural, behavioral, physiological, biochemical, developmental

Question 3

5 conditions when natural selection occurs

Answer 3

Inherited Variation – There is genetic variation within a population which can be inherited
Competition – There is a struggle for survival (species tend to produce more offspring than the environment can support)
Selection (Selection pressure) – Environmental pressures lead to differential reproduction within a population
Adaptations – Individuals with beneficial traits will be more likely to survive and pass these traits on to their offspring
Evolution – Over time, there is a change in allele frequency within the population gene pool

Question 4

Conditions for selection pressures

Answer 4

predators, availability of resources, nutrient supply, diseases, natural disasters, abiotic factors (temp./CO2 levels), weather conditions (flood/storms)

Question 5

What is adaptive radiation?

Answer 5

It describes the rapid evolutionary diversification of a single ancestral line

Question 6

What are antibiotics?

Answer 6

Chemicals produced by microbes that either kill (bactericidal) or inhibit the growth (bacteriostatic) of bacteria

Question 7

List the taxonomic groups

Answer 7

Domain, Kingdom, Phylum, Class, Order, Family, Genus and Species (Dont kill pets cos otherwise family get sad)

Question 8

List the three domains that all living organisms classify as

Answer 8

1) Eukarya – eukaryotic organisms that contain a membrane-bound nucleus (includes protist, plants, fungi and animals)
2) Archaea – prokaryotic cells lacking a nucleus and consist of the extremophiles (e.g. methanogens, thermophiles, etc.)
3) Eubacteria – prokaryotic cells lacking a nucleus and consist of the common pathogenic forms (e.g. E. coli, S. aureus, etc.)

Question 9

What is + Adv. and Dis. of natural classification

Answer 9

• Natural classification involves grouping organisms based on similarities first and then identifying shared characteristics
• According to a natural classification system, all members of a particular group would have shared a common ancestor. This means that natural classification schemes can be used to predict characteristics shared by species within a group
• A disadvantage of such schemes is that they are highly mutable and tend to change as new information is discovered

Question 10

Structure, vascularisation, reproduction, other features and examples for Bryophyta, Filicinophyta, Coniferophyta and Angiospermophyta

Answer 10

Look at rev. notes 5.2

Question 11

Symmetry, body cavity, segmentation, external features, examples of Porifera, Cnidaria, Platyhelmintha, Annelida, Mollusca, Anthropoda

Answer 11

Look at rev. notes 5.2

Question 12

Body covering, reproduction, breathing, temperature and other features of fish, smphibian, reptile, bird, mammal

Answer 12

Look at rev. notes 5.2

Question 13

Definition of Classification

Answer 13

Process of grouping living organisms that sahre similiar features

Question 14

Definition of clade

Answer 14

A group of organisms that have evolved from a common ancester

Question 15

Convergent, adaptive radiation and divergent evolution meaning

Answer 15

See Rev. notes 5.3

Question 16

Define molecular clock concept

Answer 16

When rate change of mutations is reliable, scientists can calculate year of divergence occured from number of differences per time

Question 17

3 Limitations to molecular clock concepty

Answer 17

• Different genes or proteins may change at different rates (e.g. haemoglobin mutates more rapidly than cytochrome c)
• The rate of change for a particular gene may differ between different groups of organisms
• Over lobng periods of time, earlier changes may be reversed by later changes