Chapter 18 & 19

Question 1

Four Overlapping Stages

Answer 1

1. origin of organic molecules
2. organic polymers
3. formation of boundaries
4. RNA world

Question 2

Chemical Selection

Answer 2

a chemical within a mixture has special properties that cause it to increase in number compared to other chemicals in the mixture

Question 3

Fossil

Answer 3

preserved remains of past life on earth

-radioisotope dating

Question 4

Origins of Eukaryotic cells

Answer 4

hypothesized to involve a union between bacterial & archaeal cells

Question 5

Biological Evolution

Answer 5

heritable change in one or more characteristics of a population or species from one generation to the next

Question 6

Species

Answer 6

group of related organisms

Question 7

Evidence of Evolutionary Change

Answer 7

fossil records
biogeography 
convergent evolution 
selective breeding 
homologies

Question 8

Population

Answer 8

group of individuals of the same species that occupy the same environment & can interbreed with one another

Question 9

Gene pool

Answer 9

all the alleles for every gene in a given population

Question 10

Allele frequency

Answer 10

the number of copies of a species allele in a population divided by total number of all alleles for that gene in a population

Question 11

Genotype frequency

Answer 11

number of individuals with a particular genotype in a population divided by total number of individuals in a population

Question 12

Fitness

Answer 12

relative likelihood that one genotype will contribute to the gene pool of the next generation compared with the other genotypes

Question 13

Natural Selection Patterns

Answer 13

Directional selection
stabilizing
disruptive
balancing

Question 14

Genetic drift

Answer 14

change in allele frequencies due to random change

Question 15

Migration & Nonrandom mating

Answer 15

gene flow occurs when individuals migrate between populations having different allele frequencies

Question 16

Origin of organic molecules

Answer 16

nucleotides & amino acids were produced prior to the existence of cells

Question 17

Organic Polymers

Answer 17

nucleotides became polymerized to form RNA & DNA, & amino acids become polymerized to form proteins

Question 18

Formation of boundaries

Answer 18

polymers become enclosed in membranes

Question 19

RNA world

Answer 19

polymers enclosed in membranes acquired cellular properties

Question 20

Natural Selection

Answer 20

more offspring produced than can survive
compete for limited resources
individuals with better traits flourish & reproduce

Question 21

Biogeography

Answer 21

unique species found on islands & other remote areas

Question 22

Convergent evolution

Answer 22

2 different species from different lineages sometimes become anatomically similar b/c they occupy similar environments

Question 23

Homologies

Answer 23

similar structures due to descent from a common ancestor

Question 24

Directional selection

Answer 24

individuals at one extreme of a phenotype range have greater reproductive success in a particular environment

Question 25

Stabilizing selection

Answer 25

favors the survival of individuals with intermediate phenotypes & selects against those with extreme phenotypes

Question 26

Disruptive selection

Answer 26

favors survival of 2 or more different genotypes that produce different phenotypes

Question 27

Balancing selection

Answer 27

maintains genetic diversity