Week 2

Question 1

biosphere

Answer 1

Zone of life on earth

Question 2

lithosphere (above biosphere)

Answer 2

Earth’s surface crust and upper mantle

Question 3

troposphere

Answer 3

Lowest layer of the atmosphere.

Question 4

biomes

Answer 4

Large-scale biological communities shaped by the physical environment in which they are found.

Question 5

Flowing waters (lotic)

Answer 5

streams and rivers

Question 6

still waters (lentic)

Answer 6

ponds, lakes and reservoirs

Question 7

land use change

Answer 7

Land conversion and resource extraction by humans.

Question 8

climate diagram

Answer 8

Shows the characteristic seasonal patterns of air temperature and precipitation at a representative location in that biome as well as periods of water shortages and extended periods of subfreezing temperatures.

Question 9

Understory plants

Answer 9

Plants that grow in the shade of the canopy.

Question 10

convergence

Answer 10

The evolution of similar growth forms among distantly related species in response to similar selection pressures.

Question 11

savannas

Answer 11

Communities dominated by grasses with intermixed trees and shrubs.

Question 12

desertification

Answer 12

Long-term droughts in association with unsustainable grazing practices can result in loss of plant cover and soil erosion.

Question 13

permafrost

Answer 13

A subsurface soil layer that remains frozen year-round for at least 3 years.

Question 14

dormancy

Answer 14

A period of extreme heat or cold where organisms have little or no metabolic activity in order to survive.

Question 15

enzymes

Answer 15

Protein-based molecules that catalyze biochemical reactions.

Question 16

isozymes

Answer 16

Different forms of enzymes with different temperature optima as a means of acclimatization to changes in environmental temperature.

Question 17

stomates

Answer 17

Guard cells surrounding pores that control the rate of transpiration. They also take in carbon dioxide from the atmosphere.

Question 18

pubescence

Answer 18

The presence of hairs on the leaf surface that can lower the amount of solar radiation absorbed.

Question 19

ectotherms

Answer 19

Animals that regulate their body temperature primarily through energy exchange with the external environment.

Question 20

endotherms

Answer 20

Animals that rely on internal heat generation.

Question 21

osmotic potential

Answer 21

Energy associated with dissolved solutes.

Question 22

gravitational potential

Answer 22

Energy associated with gravity.

Question 23

pressure potential

Answer 23

Energy associated with the exertion of pressure.

Question 24

matric potential

Answer 24

Energy associated with attractive forces on the surfaces of larger molecules insides cells or on the surfaces of soil particles.

Question 25

water potential

Answer 25

the sums of the energy components

Question 26

osmotic adjustment

Answer 26

An acclimatization response that involves microorganisms changing their solute concentration.

Question 27

spatial variation

Answer 27

place to place

Question 28

temporal variation

Answer 28

time to time

Question 29

Adaptations

Answer 29

heritable trait that enhances the survival and reproduction of an organism under a given set of environmental conditions.

Question 30

tradeoffs

Answer 30

There is no super-organism that can survive

Question 31

avoidance

Answer 31

a behavioral or physiological réponse of an organism to a stressful environmental condition

Question 32

migration

Answer 32

Moving to another region where condition are more favorable. Takes advantage of spatial variation in environmental conditions.

Question 33

dormancy

Answer 33

Becoming inactive during periods of adverse conditions. Takes advantage of temporal variation in conditions.

Question 34

storage

Answer 34

Reliance on resources accumulated under more favorable conditions.

Question 35

water balance

Answer 35

Driven by exchange of water solutes within external environment.

Question 36

maritime climate

Answer 36

Costal terrestrial regions that are influenced by an adjacent ocean.

Question 37

continental climate

Answer 37

Characerized by a greater variation in daily and seasonal temperatures.