Ap Enviro Ch 09

Front 1

asexual reproduction

Back 1

Reproduction in which a mother cell divides to produce two identical daughter cells that are clones of the mother cell. This type of reproduction is common in single-celled organisms. Compare sexual reproduction.

Front 2

biotic potential

Back 2

Maximum rate at which the population of a given species can increase when there are no limits on its rate of growth. See environmental resistance.

Front 3

carrying capacity (K)

Back 3

Maximum population of a particular species that a given habitat can support over a given period.

Front 4

dieback

Back 4

Sharp reduction in the population of a species when its numbers exceed the carrying capacity of its habitat. See carrying capacity.

Front 5

environmental resistance

Back 5

All the limiting factors that act together to limit the growth of a population. See biotic potential, limiting factor.

Front 6

exponential growth

Back 6

Growth in which some quantity, such as population size or economic output, increases at a constant rate per unit of time. An example is the growth sequence 2, 4, 8, 16, 32, 64 and so on; when the increase in quantity over time is plotted, this type of growth yields a curve shaped like the letter J. Compare linear growth.

Front 7

genetic drift

Back 7

Change in the genetic composition of a population by chance. It is especially important for small populations.

Front 8

intrinsic rate of increase (r)

Back 8

Rate at which a population could grow if it had unlimited resources. Compare environmental resistance.

Front 9

J-shaped curve

Back 9

Curve with a shape similar to that of the letter J; can represent prolonged exponential growth. See exponential growth.

Front 10

K-selected species

Back 10

Species that produce a few, often fairly large offspring but invest a great deal of time and energy to ensure that most of those offspring reach reproductive age. Compare r-selected species.

Front 11

K-strategists

Back 11

See K-selected species.

Front 12

limiting factor

Back 12

Single factor that limits the growth, abundance, or distribution of the population of a species in an ecosystem. See limiting factor principle.

Front 13

limiting factor principle

Back 13

Too much or too little of any abiotic factor can limit or prevent growth of a population of a species in an ecosystem, even if all other factors are at or near the optimum range of tolerance for the species.

Front 14

linear growth

Back 14

Growth in which a quantity increases by some fixed amount during each unit of time. An example is growth that increases in the sequence 2, 4, 6, 8, 10, and so on. Compare exponential growth.

Front 15

logistic growth

Back 15

Pattern in which exponential population growth occurs when the population is small, and population growth decreases steadily with time as the population approaches the carrying capacity. SeeS-shaped curve.

Front 16

monoculture

Back 16

Cultivation of a single crop, usually on a large area of land. Compare polyculture, polyvarietal cultivation.

Front 17

pathogen

Back 17

Organism that produces disease.

Front 18

population density

Back 18

Number of organisms in a particular population found in a specified area or volume.

Front 19

population dispersion

Back 19

General pattern in which the members of a population are arranged throughout its habitat.

Front 20

population distribution

Back 20

Variation of population density over a particular geographic area. For example, a country has a high population density in its urban areas and a much lower population density in rural areas.

Front 21

population dynamics

Back 21

Major abiotic and biotic factors that tend to increase or decrease the population size and age and sex composition of a species.

Front 22

population size

Back 22

Number of individuals making up a population's gene pool.

Front 23

r-selected species

Back 23

Species that reproduce early in their life span and produce large numbers of usually small and short-lived offspring in a short period. Compare K-selected species.

Front 24

r-strategists

Back 24

See r-selected species.

Front 25

reproduction

Back 25

Production of offspring by one or more parents.

Front 26

reproductive potential

Back 26

See biotic potential.

Front 27

S-shaped curve

Back 27

Leveling off of an exponential, J-shaped curve when a rapidly growing population exceeds the carrying capacity of its environment and ceases to grow.

Front 28

sexual reproduction

Back 28

Reproduction in organisms that produce offspring by combining sex cells or gametes (such as ovum and sperm) from both parents. This produces offspring that have combinations of traits from their parents. Compare asexual reproduction.

Front 29

survivorship curve

Back 29

Graph showing the number of survivors in different age groups for a particular species.

Front 30

asexual reproduction

Back 30

Reproduction in which a mother cell divides to produce two identical daughter cells that are clones of the mother cell. This type of reproduction is common in single-celled organisms. Compare sexual reproduction.

Front 31

biotic potential

Back 31

Maximum rate at which the population of a given species can increase when there are no limits on its rate of growth. See environmental resistance.

Front 32

carrying capacity (K)

Back 32

Maximum population of a particular species that a given habitat can support over a given period.

Front 33

dieback

Back 33

Sharp reduction in the population of a species when its numbers exceed the carrying capacity of its habitat. See carrying capacity.

Front 34

environmental resistance

Back 34

All the limiting factors that act together to limit the growth of a population. See biotic potential, limiting factor.

Front 35

exponential growth

Back 35

Growth in which some quantity, such as population size or economic output, increases at a constant rate per unit of time. An example is the growth sequence 2, 4, 8, 16, 32, 64 and so on; when the increase in quantity over time is plotted, this type of growth yields a curve shaped like the letter J. Compare linear growth.

Front 36

genetic drift

Back 36

Change in the genetic composition of a population by chance. It is especially important for small populations.

Front 37

intrinsic rate of increase (r)

Back 37

Rate at which a population could grow if it had unlimited resources. Compare environmental resistance.

Front 38

J-shaped curve

Back 38

Curve with a shape similar to that of the letter J; can represent prolonged exponential growth. See exponential growth.

Front 39

K-selected species

Back 39

Species that produce a few, often fairly large offspring but invest a great deal of time and energy to ensure that most of those offspring reach reproductive age. Compare r-selected species.

Front 40

K-strategists

Back 40

See K-selected species.

Front 41

limiting factor

Back 41

Single factor that limits the growth, abundance, or distribution of the population of a species in an ecosystem. See limiting factor principle.

Front 42

limiting factor principle

Back 42

Too much or too little of any abiotic factor can limit or prevent growth of a population of a species in an ecosystem, even if all other factors are at or near the optimum range of tolerance for the species.

Front 43

linear growth

Back 43

Growth in which a quantity increases by some fixed amount during each unit of time. An example is growth that increases in the sequence 2, 4, 6, 8, 10, and so on. Compare exponential growth.

Front 44

logistic growth

Back 44

Pattern in which exponential population growth occurs when the population is small, and population growth decreases steadily with time as the population approaches the carrying capacity. SeeS-shaped curve.

Front 45

monoculture

Back 45

Cultivation of a single crop, usually on a large area of land. Compare polyculture, polyvarietal cultivation.

Front 46

pathogen

Back 46

Organism that produces disease.

Front 47

population density

Back 47

Number of organisms in a particular population found in a specified area or volume.

Front 48

population dispersion

Back 48

General pattern in which the members of a population are arranged throughout its habitat.

Front 49

population distribution

Back 49

Variation of population density over a particular geographic area. For example, a country has a high population density in its urban areas and a much lower population density in rural areas.

Front 50

population dynamics

Back 50

Major abiotic and biotic factors that tend to increase or decrease the population size and age and sex composition of a species.

Front 51

population size

Back 51

Number of individuals making up a population's gene pool.

Front 52

r-selected species

Back 52

Species that reproduce early in their life span and produce large numbers of usually small and short-lived offspring in a short period. Compare K-selected species.

Front 53

r-strategists

Back 53

See r-selected species.

Front 54

reproduction

Back 54

Production of offspring by one or more parents.

Front 55

reproductive potential

Back 55

See biotic potential.

Front 56

S-shaped curve

Back 56

Leveling off of an exponential, J-shaped curve when a rapidly growing population exceeds the carrying capacity of its environment and ceases to grow.

Front 57

sexual reproduction

Back 57

Reproduction in organisms that produce offspring by combining sex cells or gametes (such as ovum and sperm) from both parents. This produces offspring that have combinations of traits from their parents. Compare asexual reproduction.

Front 58

survivorship curve

Back 58

Graph showing the number of survivors in different age groups for a particular species.