unit 2 - mechanisms of population change

Question 1

microevolution

Answer 1

variation within a species (small changes or time)

- Darwins finches

Question 2

Speciation

Answer 2

happens over a long period of time, populations evolve into distinct species

Question 3

microbial evolution

Answer 3

among viruses, bacteria, and single celled organisms

Question 4

macroevolution

Answer 4

major groups evolving into entirely new creations

Question 5

chemical evolution - abiogenesis

Answer 5

idea of life coming from no life only chemicals

Question 6

co-evolution

Answer 6

the joint evolution of two or more systems that interact with each other (ex. bees and flowers)

Question 7

divergent evolution

Answer 7

newly developed species becoming different over time

Question 8

covergent evolution

Answer 8

two different groups of organisms becoming similar over time (ex. wolf and Tasmanian wolf)

Question 9

adaptation

Answer 9

a physical feature, behavioural or physiological process that helps an organism survive and reproduce in a particular environment

Question 10

variation

Answer 10

is a visible or invisible difference that helps an individual or population survive

Question 11

mutations

Answer 11

are changes in the genetic material (DNA) of an organism, then they are passes down through offspring

Question 12

natural selection

Answer 12

the process by nature ‘selects’ which organism will or will not survive in an environment

Question 13

Anatomy - homologous

Answer 13

structures that have similar structural elements and origin but may have a different function

Question 14

anatomy - analogous

Answer 14

structures perform similar functions but do not come from the same origin

Question 15

embryology

Answer 15

closely related species go through similar stages in their embryonic development

Question 16

molecular biology

Answer 16

humans, chimps and fruit flies all share genes

Question 17

2 pathways of speciation

Answer 17

transformation - new species may result from accumulated changes in the population over a long period of time

divergence - one or more species arises from one parent which continues to exist

Question 18

adaptive radiation

Answer 18

is the diversification of a common ancestral species into a variety of species, all of which are differently shaped

Question 19

two models that scientists have proposed for the pace of evolution

Answer 19

• gradualism: slow steady, linear change over time

- punctuated equilibrium: long periods of no change interrupted by periods of speciation