Ch. 6 Evolution And Ecology

Question 1

Biological evolution -

Answer 1

Change in populations of organisms over time

Question 2

Genes can have two or more forms called ___.

Answer 2

Alleles

Question 3

___ is the genetic makeup, and can be represented by letters, one for each allele.

Answer 3

Genotype

Question 4

___ is a change in allele frequencies over time.

Answer 4

Evolution

Question 5

Evolution can be defined more broadly as ___ ___ ___.

Answer 5

Descent with modification

Question 6

Who used the phrase “descent with modification?”

Answer 6

Charles Darwin

Question 7

Proposed populations change over time through ___ ___.

Answer 7

Natural selection

Question 8

Individuals with certain __ __ survive and reproduce more successfully than individuals with other ___ ___.

Answer 8

Heritable characteristics

Question 9

Natural selection requires three attributes:

Answer 9

• genetic variation
• variation must be heritable
• differential reproductive fitness related to this variation

Question 10

Natural selection causes the two populations to ___ genetically over time.

Answer 10

Diverge

Question 11

Natural selection acts only as a ___ ___.

Answer 11

Sorting process

Question 12

Populations may evolve, but ..

Answer 12

Individuals do not evolve

Question 13

Four key processes influence evolution:

Answer 13

• mutation
• natural selection
• genetic drift
• gene flow

Question 14

Phenotype -

Answer 14

Observable characteristics of individuals that are determined by the genotype

Question 15

Why is variation so important?

Answer 15

Natural selection acts upon variation

Question 16

Different alleles arise by __.

Answer 16

Mutation

Question 17

Mutation results from:

Answer 17

• copying errors during cell division
• mechanical damage
• exposure to certain chemicals
• exposure to high energy radiation

Question 18

Homogeneity -

Answer 18

Lack genetic variation

Question 19

Mutation is the “___ ___” of variation.

Answer 19

Raw material

Question 20

__ is essentially a random process.

Answer 20

Mutation

Question 21

Individuals in a population differ genetically because of both mutation and ___.

Answer 21

Recombination

Question 22

Mutations occur too rarely to be direct cause of ___ ___ change.

Answer 22

Allele frequency change

Question 23

Natural selection -

Answer 23

Occurs when individuals with particular heritable traits tend to leave more offspring than individuals with other heritable traits

Question 24

What is the only process that consistently results in adaptive evolution?

Answer 24

Natural selection

Question 25

Natural selection can be categorized into three types:

Answer 25

• directional selection
• stabilizing selection
• disruptive selection

Question 26

Directional selection -

Answer 26

Individuals with one extreme of a heritable phenotypic trait are favored

Ex: drought favored large beak size in medium ground finches -> eating larger seeds

Question 27

Stabilizing selection -

Answer 27

Individuals with an intermediate phenotype are favored

Ex: parasitic wasps select against small gall size, birds select against large gall size -> medium size galls

Question 28

Disruptive selection -

Answer 28

Individuals at both phenotypic extremes are favored

Ex: African seedcrackers have two food sources -> really small seeds and really big seeds -> caused disruptive selection -> some birds got big beaks and some birds got small beaks

Question 29

Altruism -

Answer 29

Helping others when it costs you

Question 30

Typically there is a selfish interest called ___.

Answer 30

Cooperation