ecosystems test

Question 1

what is symbiosis

Answer 1

relationships between organisms

Question 2

what is commensalism

Answer 2

where one organism benefits and the other is neither harmed nor benefitted

Question 3

what is mutualism

Answer 3

when both organisms benefit

Question 4

what is parasitism

Answer 4

when one organism benefits and the other is harmed

Question 5

how do ecologists study populations?

Answer 5

by examining their geographic range, growth rate, density and distribution, and age structure

Question 6

what factors affect population growth

Answer 6

birth rate, death rate, and migration

Question 7

what happens during exponential growth?

Answer 7

the larger the population gets, the faster it grows

Question 8

what happens during logistic growth?

Answer 8

The population begins growing exponentially, it slows down, and then the rate of pop. growth reaches 0

Question 9

_________ demonstrates how genetics and evolution influence each other

Answer 9

population genetics

Question 10

How many factors change allele frequency within a population?

Answer 10

5

Question 11

How does sexual selection change the population

Answer 11

Sexual selection changes the population because the traits that attract the most mates are going to show up more often in the Gene pool

Question 12

Changes in allele frequency due to random chance is…

Answer 12

genetic drift

Question 13

Changes in allele frequency due to mixing with new genetically different populations

Answer 13

Gene flow

Question 14

What principle states that under the right circumstances Mendelian genetics works at the scale of a whole population

Answer 14

Hardy-Weinberg Principle

Question 15

The Hardy-Weinberg equilibrium requires..

Answer 15

No natural selection, no sexual selection, gigantic population size, no mutations, no gene flow

Question 16

What is the Hardy Weinberg equation?

Answer 16

p^2+2pq+q^2 (q= freq. of recessive allele, p = freq. of dominant allele)

Question 17

What factors determine carrying capacity?

Answer 17

Limiting factors

Question 18

What limiting factors depend on population density?

Answer 18

Density dependent factors like competition, stress, parasitism, disease, predation, and herbivory

Question 19

What limiting factors do not typically depend on population density

Answer 19

Environmental extremes such as hurricanes, droughts, floods, natural disasters, and temperature

Question 20

What is the relationship between limiting factors and extinction

Answer 20

If limiting factors causes the carrying capacity to fall low enough, populations can become extinct

Question 21

Intrinsic growth rate is

Answer 21

whether the pop. is increasing or decreasing

Question 22

A type 1 survivorship curve is most similar to the growth pattern of

Answer 22

K selected species

Question 23

What is a K selected species?

Answer 23

Species that live long with parental care

Question 24

What is a r selected species

Answer 24

Species that live shorter without parental care

Question 25

What are the levels of organization in ecology

Answer 25

Biosphere, ecosystem, community, population, organism

Question 26

What is the competitive exclusion principle?

Answer 26

A principle stating that no two species can occupy exactly the same niche in exactly the same habitat at exactly the same time

Question 27

How do keystone species shape communities

Answer 27

If they are removed from an area, it can cause the ecosystem in that area to collapse entirely

Question 28

What is the Anthropocene

Answer 28

The period during which human activity has become the major cause of global change

Question 29

What are the steps of Ocean acidification

Answer 29

Carbon dioxide is released from fossil fuels burning, dissolves in seawater, and turns into acid

Question 30

What kinds of pollutants are drivers of global change?

Answer 30

CFCs (industrially produced gasses), smog, waste, DDT (a pesticide), PCBs (toxic chemicals causing water pollution), and heavy metals

Question 31

What is the goal of a compost bin

Answer 31

Nutrient rich organic material

Question 32

Where can carbon be found

Answer 32

Fossil fuels, living organisms, the ocean, atmosphere, rocks

Question 33

After a long long time, the carbon from the remains of dead organisms can be stored in

Answer 33

fossil fuels

Question 34

what percent of the air is nitrogen

Answer 34

78%

Question 35

nitrogen can be fixed by what in the roots of some plants and in the soil

Answer 35

bacteria

Question 36

What are the key processes of the carbon cycle?

Answer 36

Photosynthesis, cellular respiration, decomposition, fossilization, and combustion

Question 37

What are the key processes of the nitrogen cycle?

Answer 37

Nitrogen fixation, nitrification, assimilation, ammonification, and denitrification

Question 38

What is nitrogen fixation?

Answer 38

Bacteria converts nitrogen gas into ammonium ions

Question 39

What is nitrification

Answer 39

The process of turning ammonium ions into nitrites and nitrates via nitrofying bacteria

Question 40

What is assimilation

Answer 40

The uptake of nitrate from the soil by the roots of plants

Question 41

What is ammonification

Answer 41

Decomposers turn nitrogen compounds into ammonium

Question 42

What is denitrification

Answer 42

The process of turning nitrates into nitrogen gas via denitrifying bactera

Question 43

The precipitation that hits the ground can run off when

Answer 43

The ground is saturated like a sponge or if it is hard scaped like roads

Question 44

How do plants get phosphate molecules

Answer 44

Fertilizer and soil

Question 45

How are layers of new sedimentary rock containing phosphorus formed

Answer 45

The phosphorus compounds in the water and organisms sink to the ocean floor and form the layers

Question 46

What is Eutrophication

Answer 46

a process by which too much phosphorus runs off into bodies of water

Question 47

What are the key processes of the water cycle?

Answer 47

Evaporation, transpiration, condensation, precipitation, and percolation

Question 48

What is percolation?

Answer 48

When water moves through soil layers back to lakes and oceans.

Question 49

What are the key processes of the phosphorus cycle

Answer 49

Weathering, Surface runoff and fertilizer run off, decomposition, sedimentation, and uplift

Question 50

What is weathering

Answer 50

The physical and chemical breakdown of rocks

Question 51

What is sedimentation

Answer 51

Dead marine organisms get compacted by sediment forming sedimentary rocks

Question 52

What is uplift

Answer 52

A geological process that moves rocks from oceans onto the land

Question 53

How much energy is passed from one level of a food pyramid to the next?

Answer 53

10%

Question 54

Why is a food web better than a food chain at representing interactions in an ecosystem?

Answer 54

It is a combination of multiple food chains put together shows the different relationships.