Lecture 37 - Our Global Environment/Ecology/Biosphere I Flashcards Preview

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Flashcards in Lecture 37 - Our Global Environment/Ecology/Biosphere I Deck (43):
1

What is ecology?

scientific study of interactions between organisms + the environment

2

What are the 6 levels of ecology?

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

3

What is the biosphere?

-global ecosystem
-sum of all the planet's ecosystems

4

What is global ecology?

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

5

What is a landscape?

-mosaic of connected ecosystems

6

What is landscape?

-mosaic of connected ecosystems

7

What is landscape ecology?

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

8

What is an ecosystem?

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

9

What is ecosystem ecology?

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

10

What is a community?

group of populations of different species in an area

11

What is community ecology?

-examines effect of interspecific interactions on community structure and organization

12

What is a population?

-group of individuals of same species living in an area

13

What is population ecology?

-focuses on factors affecting population size over time

14

What is organismal ecology?

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

15

What are abiotic factors?

-temperature, light, water, nutrients

16

What are biotic factors?

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

17

What are biomes? What are they characterized by?

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

18

What are 2 types of climate?

-macro
-micro

19

What is dispersal?

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

20

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

abiotic factors

21

What are 5 biotic factors that affect distribution of organisms?

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

22

similar characteristics can arise in distant biomes through _______

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

23

Population growth is ____ under ____ conditions

exponential
idealized

24

What is r

growth rate

25

Why is exponential population growth unrealistic?

-population will reach carrying capacity (K)

26

What is carrying capacity? (K)

maximum amount the environment can support

27

6 factors that are affected by density

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

28

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

-dense
-emigration

29

What are metapopulations

-groups of populations linked by immigration and emigration

30

What are 3 main variables of life history?

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

31

What is semelparity?

"big-bang" reproduction
-reproduce once and die

32

What is iteroparity?

-repeated reproduction
-produce offspring repeatedly

33

Which kind of environments favor semelparity?

-variable/unpredictable environments

34

Which environments favor iteroparity?

dependable environments

35

What is k-selection?

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

36

What is r-selection?

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

37

When did human population start growing exponentially?

1650

38

When did growth of the human population slow?

1960s

39

Different populations in the world go through _____ at different times

demographic transition

40

What is demographic transition?

high birth/death rate to low birth/death rate

41

What is a major factor associated with demographic transition?

-improved healthcare/education for women

42

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

age structure pyramids

43

What is an ecological footprint?

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