Evolution, Ageing and Death

Question 1

Biological evolution

Answer 1

change in population or species over time

Question 2

Adaptation

Answer 2

a trait or characteristic that increases the reproductive success of an organism, produced by natural selection in the context of a particular environment

Question 3

biological evo. decent from a common ancestor

Answer 3

explains why life has a common chemistry and cellular structure

Question 4

biological evo. adaptation to the environment

Answer 4

explains the diversity of life and why there are so many different types of organisms

Question 5

scientific theory

Answer 5

a statement of well-supported laws, principles or causes of something known or observed
we can make predictions and testable hypotheses
we can make direct observations or events or objects
specific hypotheses are under constant modification, testing and re-evaluation

Question 6

Charles Darwin’s idea of biological evolution

Answer 6

Natural selection: a mechanism for adaptation whereby species become suited to their enviroment

Question 7

3 vital elements of natural selection

Answer 7

variation
competition
adaptation

Question 8

Variation

Answer 8

there must be physical variations that can be passed from generation to generation

Question 9

Competition

Answer 9

there must be competition for limited resources (food, mates, shelter), and those better adapted will survive and reproduce

Question 10

Adaptation

Answer 10

subsequent generations will see an increase in individuals with the same adaptations, as long as the environment remains unchanged

Question 11

Lamarck’s vs Darwin’s proposal

Answer 11

Lamarck: acquired characteristics cannot be inherited
Darwin: the environment ‘selects’ for better-adapted traits that can be inherited

Question 12

how humans selected organisms with certain traits, examples

Answer 12

modern domestic dog breeds are descendants of the grey wolf
cabbage, brussels sprouts, broccoli and cauliflower are derived from a single species of wild cabbage

Question 13

types of anatomical evidence for evolution

Answer 13

Homologous
Analogous
Vestigial

Question 14

Homologous structures

Answer 14

structures anatomically similar that are inherited by a common ancestor (ie. pentadactyl vertebrate forelimb)
Same structure, different function

Question 15

Analogous structures

Answer 15

structures that serve the same function, but they do not share a common ancestry, and thus are not constructed the same (ie. bat wings and insect wings)
Same function, different structure

Question 16

Vestigial structures

Answer 16

anatomical features full developed in one group that are reduced and may have no function in another group (ie. whales pelvic girdle, human 3rd molars, rudimentary ear muscles, palmaris longs muscle, coccyx)