Lecture 37 - Our Global Environment/Ecology/Biosphere I

Question 1

What is ecology?

Answer 1

scientific study of interactions between organisms + the environment

Question 2

What are the 6 levels of ecology?

Answer 2

1. global
2. landscape
3. ecosystem
4. community
5. population
6. organismal

Question 3

What is the biosphere?

Answer 3

• global ecosystem

- sum of all the planet’s ecosystems

Question 4

What is global ecology?

Answer 4

-examines influence of energy + materials on organisms across the biosphere

Question 5

What is a landscape?

Answer 5

-mosaic of connected ecosystems

Question 6

What is landscape?

Answer 6

-mosaic of connected ecosystems

Question 7

What is landscape ecology?

Answer 7

-focuses on exchanges of energy, materials + organisms across multiple ecosystems

Question 8

What is an ecosystem?

Answer 8

-community of organisms in an area + physical features they interact with

Question 9

What is ecosystem ecology?

Answer 9

-emphasizes energy flow + chemical cycling among various biotic + abiotic components

Question 10

What is a community?

Answer 10

group of populations of different species in an area

Question 11

What is community ecology?

Answer 11

-examines effect of interspecific interactions on community structure and organization

Question 12

What is a population?

Answer 12

-group of individuals of same species living in an area

Question 13

What is population ecology?

Answer 13

-focuses on factors affecting population size over time

Question 14

What is organismal ecology?

Answer 14

-studies how an organism’s structure, physiology + behavior meet environmental challenges

Question 15

What are abiotic factors?

Answer 15

-temperature, light, water, nutrients

Question 16

What are biotic factors?

Answer 16

-other organisms that are part of an individual’s environment

Question 17

What are biomes? What are they characterized by?

Answer 17

• major life zones

- characterized by vegetation type (terrestrial) or physical environment (aquatic)

Question 18

What are 2 types of climate?

Answer 18

• macro

- micro

Question 19

What is dispersal?

Answer 19

-movement of individuals or gametes away from centers of high population density or area of origin

Question 20

The ability for a species to disperse or transplant often depends upon _____

Answer 20

abiotic factors

Question 21

What are 5 biotic factors that affect distribution of organisms?

Answer 21

1. predation
2. herbivory
3. competition
4. mutualism
5. parasitism

Question 22

similar characteristics can arise in distant biomes through _______

Answer 22

convergent evolution

EX: cacti in N. America and euphorbs in African deserts

Question 23

Population growth is ____ under ____ conditions

Answer 23

exponential

idealized

Question 24

What is r

Answer 24

growth rate

Question 25

Why is exponential population growth unrealistic?

Answer 25

-population will reach carrying capacity (K)

Question 26

What is carrying capacity? (K)

Answer 26

maximum amount the environment can support

Question 27

6 factors that are affected by density

Answer 27

1. competition for resources 2. disease 3. predation 4. territoriality 5. intrinsic 6. toxic wastes

Question 28

As population becomes more ______ this leads to movement out or _____

Answer 28

- dense | - emigration

Question 29

What are metapopulations

Answer 29

-groups of populations linked by immigration and emigration

Question 30

What are 3 main variables of life history?

Answer 30

1. age at which reproduction begins 2. how often the organism reproduces 3. how many offspring are produced per reproductive episode

Question 31

What is semelparity?

Answer 31

"big-bang" reproduction | -reproduce once and die

Question 32

What is iteroparity?

Answer 32

- repeated reproduction | - produce offspring repeatedly

Question 33

Which kind of environments favor semelparity?

Answer 33

-variable/unpredictable environments

Question 34

Which environments favor iteroparity?

Answer 34

dependable environments

Question 35

What is k-selection?

Answer 35

- density dependent selection | - selects for life history traits that are sensitive to population density

Question 36

What is r-selection?

Answer 36

- density-independent selection | - selects for life history traits that maximize reproduction

Question 37

When did human population start growing exponentially?

Answer 37

1650

Question 38

When did growth of the human population slow?

Answer 38

1960s

Question 39

Different populations in the world go through _____ at different times

Answer 39

demographic transition

Question 40

What is demographic transition?

Answer 40

high birth/death rate to low birth/death rate

Question 41

What is a major factor associated with demographic transition?

Answer 41

-improved healthcare/education for women

Question 42

What figure can you use to tell what stage of the demographic transition that a country is in?

Answer 42

age structure pyramids

Question 43

What is an ecological footprint?

Answer 43

summarizes aggregate land and water area needed to sustain the people of a nation