Exam 1 Material

Question 1

Ecology:

Answer 1

Relationship between organisms and their environment

Question 2

Habitat:

Answer 2

is the physical location of a species

Question 3

Ecological niche:

Answer 3

total way of life or functional role of a species in an ecosystem

Question 4

Population:

Answer 4

One species, same place and time

Question 5

Community:

Answer 5

Assemblage of organisms in a habitat

Question 6

Ecosystem:

Answer 6

All populations in a community with their physical environment

Question 7

Biosphere:

Answer 7

Thin outer layer of earth capable of supporting life (land, water, atmosphere)

Question 8

Population size:

Answer 8

the number of individuals in a population

Question 9

Population density:

Answer 9

number of individuals living in a given area

Question 10

Population distribution:

Answer 10

the way individuals are arranged in space

Question 11

Distribution:

Answer 11

spacing of individuals relative to each other

Question 12

Clumped:

Answer 12

concentrated in specific parts of habitat, common.

Question 13

Uniform:

Answer 13

evenly spaced in habitat, less common

Question 14

Random:

Answer 14

spacing unrelated to presence of others, rare-animals

Question 15

Population growth:

Answer 15

difference between rates of birth and death. effected on a local scale by dispersal (movement of individuals among populations)

Question 16

Survivorship Curve
Type 1:

Answer 16

Young and those at reproductive age have a high probability of surviving.

Question 17

Survivorship Curve
Type 2:

Answer 17

> Probability of survival doesn’t change with age
E.g. adult bird, rodents

Question 18

Survivorship Curve
Type 3:

Answer 18

Probability of mortality greatest early in life

Question 19

Age Structures:

Answer 19

population growth slows as countries become more industrialized

Question 20

Carrying Capacity (K):

Answer 20

> Largest population that can be maintained for a given amount
No population can increase exponentially indefinitely
Populations rarely stabilize at K
Populations that overshoot K may crash

Question 21

Population crash:

Answer 21

abrupt decline from high to low density

Question 22

Exponential Growth:

Answer 22

> Accelerating population growth rate
J shaped curve

Question 23

Density Dependent factors:

Answer 23

> Influence varies with density of population
Slows growth at high densities and increases it at low densities to regulate around K
Predation, disease, competition

Question 24

Population Cycles:

Answer 24

an absence of predators allows an herbivore population to exceed carrying capacity, which results in overgrazing of the habitat

Question 25

Density Independent factors:

Answer 25

>Environmental factor that affects population size >Not influenced by changes in density >Weather, fire

Question 26

Primary producers (autotrophs):

Answer 26

make organic molecules from inorganic substances; photosynthesis

Question 27

Heterotrophs (consumers);

Answer 27

Obtain energy by feeding on other organisms

Question 28

Decomposers:

Answer 28

break down organic material and use products for energy

Question 29

Predator-Prey interactions:

Answer 29

>Involve continuous evoluntionary change

Question 30

Aposematic warning coloration:

Answer 30

Conspicuous markings make animal easy to recognize and warn predators

Question 31

Cryptic coloration:

Answer 31

match background to hide from predator (or prey)

Question 32

Mimicry:

Answer 32

resemblance of species to another or aspect of its environment

Question 33

Symbiosis:

Answer 33

association in which two species live together tin a close relationship

Question 34

Mutualism:

Answer 34

Both members benefit

Question 35

Commensalism:

Answer 35

one of the partner species benefits and the other partner is unaffected

Question 36

Parasitism:

Answer 36

one member of the relationship benefits while the other is harmed

Question 37

Competiton:

Answer 37

struggle for 2 organisms to use limited resources

Question 38

Competitive exclusion:

Answer 38

one species eliminates the other

Question 39

Fundamental niche:

Answer 39

theoretical niche organism would occupy in the absence of competition

Question 40

Realized niche:

Answer 40

actual niche organism occupies in nature

Question 41

Resource Partitioning:

Answer 41

Natural selection favors individuals of species that reduce competition for resources

Question 42

Character displacement:

Answer 42

when two species diverge more in sympatry then they do in allopatry, this reduces competition

Question 43

Sympatry:

Answer 43

they live in the same place

Question 44

Allopatry:

Answer 44

they live in two different places

Question 45

Keystone Species:

Answer 45

interacts in critical ways with the ecosystem

Question 46

Evolution:

Answer 46

changes in allele frequencies of a population over generations

Question 47

Aristotle:

Answer 47

>greek philosopher >Scala naturae-great chain of being >No mechanism proposed >Fossils were former life

Question 48

Georges-Louis Buffon:

Answer 48

>French naturalist >Earth was very old (70,000 years) >Influence of environment on modifications on animal form

Question 49

Jean-Baptiste Lamarck:

Answer 49

>fossils were remains of extinct animals >inheritance of acquired characteristics >emphasized great age of the earth >ideas almost universally rejected

Question 50

Charles Lyle:

Answer 50

>small forces acting over long periods of time >influenced Darwin

Question 51

Charles Darwin:

Answer 51

>characteristics of species varied from place to place >great variety of organisms on young volcanic islands

Question 52

Alfred Russel Wallace:

Answer 52

He wrote Darwin expressing the same ideas which prompted Darwin to write On the Origin of Species

Question 53

Origin of Species:

Answer 53

>All organisms have descended with modification from common ancestors >Chief agent of modification is action of natural selection on individual variation

Question 54

Natural Selection:

Answer 54

>Differential survival and/or reproduction of individuals that differ in one or more heritable traits >Better adapted organisms are more likely to survive and become the parents of the next generation

Question 55

How Natural Selection Operates:

Answer 55

>Overproduction >Heritable variation >Limits on population growth >Differential reproductive success

Question 56

Endler Selection Experiment:

Answer 56

Spots can help guppies blend with their environment but males also need spots to attract females

Question 57

Population:

Answer 57

All of the individuals of the same species that live in a particular place at the same time

Question 58

Gene Pool:

Answer 58

>Sum total of all genes possessed by all the individuals in the population >Characterized by allele frequencies

Question 59

Allele Frequency:

Answer 59

Percentage of a specific allele of a given gene locus in the population

Question 60

Stabilizing Selection:

Answer 60

> Two or more opposing selection pressures >Selects against extreme phenotypes - Shifts phenotypic curve toward average >Decreases diversity

Question 61

Disruptive Selection:

Answer 61

>Directional selection pressures favoring the two extremes >Acts against the average phenotype

Question 62

Species:

Answer 62

Groups of populations that are reproductively isolated from other groups of populations Members of the same species can interbreed and produce fertile offspring

Question 63

Reproductive Isolating Mechanisms:

Answer 63

Prevent successful mating

Question 64

Prezygotic vs. Postzygotic:

Answer 64

> prevent fertilization >prevent gene flow when mating occurs

Question 65

Temporal:

Answer 65

Do not breed at the same time of day or season

Question 66

Ecological:

Answer 66

Use different habitats Will hybridize if contact

Question 67

Behavioral:

Answer 67

Differences in courtship rituals

Question 68

Mechanical:

Answer 68

Structural differences in reproductive organs

Question 69

Gametic incompatibility:

Answer 69

a. sperm transfer takes place but egg is not fertilized b. gametes are chemically incompatible c. ex. external fertilization in sponges

Question 70

Hybrid inviability:

Answer 70

die as embryos or shortly after birth

Question 71

Hybrid sterility:

Answer 71

sterile hybrid (ex: mules; horse x donkey)

Question 72

Hybrid breakdown:

Answer 72

male lion x female tiger a. F1: liger (female) b. F2: generation has lower fitness

Question 73

Sympatric Speciation:

Answer 73

population diverging in same physical location

Question 74

Phyletic Gradualism (Darwin):

Answer 74

a. speciation occurs gradually and stasis is apparent rather than real b. transitional links should be found c. an ancestral species can be transformed into a new species

Question 75

Punctuated Gradualism (Gould and Eldridge):

Answer 75

a. speciation occurs rapidly and then a species experiences stasis b. transitional links will not necessarily be found c. a subpopulation of the ancestral species become a new species

Question 76

Adaptive Radiation:

Answer 76

Evoluntionary diversification from common ancestral sock Most common during periods of big environmental change