Ch. 10 Natural Selection

Question 1

tuberculosis

Answer 1

single-celled bacterium. destroys lung tissue

Question 2

antibiotics

Answer 2

kill certain nonhuman bacterial cells

Question 3

antibiotic resistant

Answer 3

must use second-line drugs

Question 4

MDR-TB

Answer 4

multi-drug resistant tuberculosis

Question 5

XDR-TB

Answer 5

extensive drug resistant tuberculosis

Question 6

natural selection

Answer 6

inference based on 4 observations:

1. individuals within populations vary
2. some variation may be inherited
3. populations produce more offspring than will survive
4. survival and reproduction are not random

Question 7

individual in populations vary

Answer 7

dog may have litter with some black and some white

Question 8

variant

Answer 8

each different type of individual in a population

Question 9

some variation may be inherited

Answer 9

resemblance between parent and offspring

Question 10

populations produce more offspring that will survive

Answer 10

trees make million of seeds every year. capacity for reproduction far outstrips the environmental resources

Question 11

survival and reproduction are not random

Answer 11

some variants are more likely to survive. fitness and adaptations

Question 12

fitness

Answer 12

relative survival and reproduction of one variant compared to others

Question 13

adaptations

Answer 13

traits that increase fitness in a particular environment

Question 14

inference

Answer 14

favorable inherited traits tend to increase over time while unfavorable traits are lost

Question 15

artificial selection

Answer 15

selection imposed by human choice. deliberately control survival and reproduction of organisms with favorable traits to change the population

Question 16

natural selection in lab

Answer 16

looking for adaptations of populations to environments manipulated in lab settings

Question 17

natural selection in wild populations

Answer 17

examples are drug resistant pathogens and the bill size in galapagos finches in response to drought

Question 18

modern synthesis

Answer 18

union between genetics and evolution. gene mutations provide the variation needed for evolution

Question 19

subtleties of natural selction

Answer 19

doesn’t cause evolution of perfect organisms.

1. cant make new traits arise
2. doesn’t result in perfection. only improves fitness in the current environment
3. no progression toward a goal. only adapt to current environment

Question 20

jury rigged design

Answer 20

adaptations using whatever underlying biology is available (‘thumbs’ on pandas)

Question 21

directional selection

Answer 21

population traits move in a particular direction. typically leads to change in a population over time

Question 22

stabilizing selection

Answer 22

populations tend to resist change in unchanging environments. the extreme variants are selected against and the average is in favor

Question 23

diversifying selection

Answer 23

populations with 2 or more variants. likely if different subpopulations are experiencing different environments

Question 24

tuberculosis and natural selection

Answer 24

1. bacteria in population vary, every time reproduction occurs mutation can happen
2. variation can be passed to offspring. drug resistant traits are coded in its DNA
3. more bacteria are produced than survive. antibiotic treatment eliminate the majority
4. survival isnt random. bacteria with traits making them more resistant are more likely to survive

Question 25

drug resistance

Answer 25

patient stops treatment after symptoms are eliminated, leaving the more resistant bacteria still alive. the resistant strain reproduces and the disease returns and is much more difficult to control

Question 26

stopping resistance

Answer 26

maintain drug therapy for several months, or use multiple drugs

Question 27

combination drug therapy

Answer 27

drug cocktail therapy. the greater number of drugs used, the greater number of changes are required to become resistant