Exam One

Question 1

Define evolution

Answer 1

The change in genetic composition of populations over time

Question 2

Define evolutionary theory

Answer 2

Large body of accumulated science on what evolutionary changes have occurred and how they occur

Question 3

What are the three principles of Darwin’s theory?

Answer 3

1. ) Species change over time
2. ) Divergent species share a common ancestor
3. ) The change in species can be explained by natural selection

Question 4

Define natural selection

Answer 4

Increased survival and reproduction of some individuals compared with others due to preferable traits

Question 5

Define population

Answer 5

Group of individuals of a single species that live and interbreed in a particular geographic area at the same time

Question 6

Fill in the blank:

Individuals do not evolve; ________ do.

Answer 6

Populations

Question 7

What are the five processes for evolution?

Answer 7

1. ) Mutations
2. ) Selection
3. ) Gene flow
4. ) Genetic drift
5. ) Non-random mating

Question 8

Define mutation

Answer 8

Change in sequence of organism’s DNA

Question 9

Are mutations helpful, harmful, or random in that sense?

Answer 9

Random

Question 10

Define adaptation

Answer 10

1. ) Favored trait that evolves through natural selection

2. ) The process of evolving favored traits

Question 11

What is the difference between stabilizing, directional, and disruptive selection?

Answer 11

Stabilizing favors average individuals.
Directional favors one extreme.
Disruptive favors both extremes.

Question 12

Define genetic drift

Answer 12

Random changes in allele frequencies in generations

Question 13

When is genetic drift most likely to occur?

Answer 13

Smaller populations as a result of “population bottlenecks”

Question 14

Define founder effect

Answer 14

Small number of individuals colonize new area; unlikely to include all genetic variation of source population

Question 15

Why does non-random mating affect allele frequencies?

Answer 15

1. ) An organism that survives but fails to reproduce makes no contribution to the next generation.
2. ) Traits evolved to appeal to non-random mating can harm chances of survival (i.e. bright feathers can be appealing to mates but also predators)

Question 16

How is evolution measured?

Answer 16

Changes in allele/genotype frequencies over time

Question 17

Define Hardy-Weinberg equilibrium

Answer 17

Purely theoretical situation where evolution does not occur

1. ) No mutation
2. ) No selection among genotypes
3. ) No gene flow
4. ) Huge population size
5. ) Mating is random

Question 18

Define genome

Answer 18

Complete DNA sequence

Question 19

Define phylogeny

Answer 19

Evolutionary history of organisms

Question 20

Define phlyogenetic tree

Answer 20

Diagram of evolutionary history organized by lineage

Question 21

Define ancestral trait and derived trait

Answer 21

Ancestral trait: initial condition

Derived trait: new condition

Question 22

Define morphology

Answer 22

Physical characteristics

Question 23

Define paleontology

Answer 23

Study of fossils

Question 24

Define molecular data

Answer 24

DNA, genome

Question 25

Define species

Answer 25

1. ) Groups of organisms that mate with one or another 2. ) Groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups

Question 26

Define reproductive isolation

Answer 26

Situation where two groups of organisms cannot exchange genes

Question 27

Define taxonomy and systemics

Answer 27

Science of classifying and naming species

Question 28

Define habitat partitioning

Answer 28

Speciation dependent on fulfilling survival/reproductive niche (i.e. birds that become separate in diet and their abilities to fulfill their dietary needs)

Question 29

What are the limitations of hybridization?

Answer 29

1. ) Mechanical isolation: reproductive organs are physically incompatible 2. ) Temporal isolation: species have different mating seasons, so are partitioned in time 3. ) Behavioral isolation: rejection or failure to recognize individuals of other species as mating partners.

Question 30

Define hybrid zones

Answer 30

Areas where hybridization can still occur

Question 31

Define de-extinction

Answer 31

Science of bringing extinct species back to life

Question 32

Define binomial nomenclature

Answer 32

Two part naming system: 1. ) Genus 2. ) Specific identifier i.e. Homo sapiens

Question 33

Define half-life

Answer 33

Half of the atoms in a radioisotope decay to become a different, stable, isotope; basis for radiometric dating

Question 34

Define plate tectonics

Answer 34

Movement of major land masses

Question 35

What happens in response to dramatic changes in Earth's physical environment?

Answer 35

Mass extinctions

Question 36

What words describe earth's conditions on a short-term and long-term basis?

Answer 36

Short-term: weather | Long-term: climate

Question 37

Define fossil

Answer 37

Remains or impression of an ancient organism

Question 38

Define prokaryote

Answer 38

Single-celled organism lacking nucleus

Question 39

Define eukaryote

Answer 39

Multi-cellular organism with genetic material in a nucleus

Question 40

Define endosymbiosis

Answer 40

Engulfment of one cyanobacterium by larger eukaryotic cell

Question 41

Define chloroplasts

Answer 41

Enzymes and pigments that perform photosynthesis and only occur in eukaryotes

Question 42

Define alternation of generations

Answer 42

Process that includes a multicellular diploid stage (sporophyte) and a multicellular haploid stage (gametophyte). Spores develop into gametophytes.

Question 43

Define gametes

Answer 43

Mature reproductive cell (egg or sperm)

Question 44

Define vascular plants (tracheophytes)

Answer 44

Well developed vascular systems with fluid-containing cells called tracheids

Question 45

Define nonvascular plants

Answer 45

Plants in which some have conduction cells, but no tracheids

Question 46

Define tracheids

Answer 46

A type of water-conducting cell in the xylem; used for transport

Question 47

Give examples of nonvascular plants

Answer 47

Liverworts, mosses, hornworts

Question 48

Where do nonvascular plants live?

Answer 48

Moist habitats

Question 49

How big are nonvascular plants and why?

Answer 49

Generally small because the lack of transport of water; must rely on diffusion

Question 50

What do liverworts look like?

Answer 50

Green, leaflike gametophytes

Question 51

Mosses have what important structure that is important in gas exchange and water retention?

Answer 51

Stomata

Question 52

# Fill in the blank: Mosses have a similar structure to tracheids called ____.

Answer 52

Hydroids

Question 53

Where do mosses live?

Answer 53

Almost all land environments

Question 54

What do hornworts' sporophytes look like?

Answer 54

Small horns

Question 55

How many chloroplasts do the cells of hornworts contain?

Answer 55

One chloroplast

Question 56

The sporophytes grow from where and can divide how many times?

Answer 56

Basal region; infinite

Question 57

Hornworts have symbiotic relationships with what? Where do they live? What do they do?

Answer 57

Cyanobacteria; internal caveties; nitrogen fixation

Question 58

Define vascular system

Answer 58

System consisting of tissues specialized for the transport of water and materials from one part of the plant to another.

Question 59

Define xylem

Answer 59

Structure that conducts water and minerals from the soil to the aerial parts of the plant.

Question 60

Phloem

Answer 60

Structure that conducts products of photosynthesis from production sites to use or storage sites.

Question 61

What is the significance of lignin?

Answer 61

Exists in cell walls to provide structural support, allowing taller growth

Question 62

Define monilophytes

Answer 62

horsetails and ferns

Question 63

What do the leaves of the horsetails look like?

Answer 63

They're smaller and in whorls

Question 64

# Fill in the blank: Horsetails have an independent ________ and _______.

Answer 64

Sporophytes and gametophytes

Question 65

Define seed plants

Answer 65

Gymnosperms and angiosperms

Question 66

What are the significance of seeds?

Answer 66

Seeds provide a secure and lasting dormant stage for the embryo. They also provide nutrients when the embryo begins to grow.

Question 67

What is the male gametophyte in seed plants? What is its significance?

Answer 67

Pollen grain; contains sporopollenin which prevents drying and chemical damage.

Question 68

Define secondary growth

Answer 68

Increasing diameter of roots and stems by growth of xylem (forms wood)

Question 69

Define gymnosperms

Answer 69

Seed plants that do not form flowers or fruits

Question 70

Gymnosperms produce "naked seeds", which means what?

Answer 70

The ovules and seeds are not protected by ovary or fruit tissue

Question 71

Gymnosperms include conifers, which mean what?

Answer 71

Cone-bearing plants

Question 72

Define cuticles

Answer 72

a waxy coating that slows water loss

Question 73

Define stomata

Answer 73

closable openings that regulate gas exchange and water loss

Question 74

Embryos

Answer 74

young plants contained within a protective structure