lesson 23

Question 1

What is the biosphere?

Answer 1

All of the living communities on Earth

Question 2

What modifies solar energy before it reaches Earth’s surface?

Answer 2

Reflection and absorption by the atmosphere.

Question 3

What is the greenhouse effect?

Answer 3

Trapped heat in the lower atmosphere warms the Earth.

Question 4

Why is there less solar warming near the poles?

Answer 4

Solar rays are spread over a larger area due to Earth’s curvature.

Question 5

What causes seasonal changes on Earth?

Answer 5

Earth’s tilt and orbit around the Sun.

Question 6

Where is mean annual temperature highest and most stable

Answer 6

At the equator.

Question 7

Why does air rise at the equator?

Answer 7

Warm air rises, holds more moisture, and causes high precipitation.

Question 8

Why are deserts found at 30° latitude?

Answer 8

Dry air sinks and evaporates moisture from land surfaces.

Question 9

What causes surface winds to curve?

Answer 9

the Coriolis effect due to Earth’s rotation.

Question 10

What drives ocean surface currents?

Answer 10

Surface winds powered by the Sun.

Question 11

What is a gyre?

Answer 11

A large closed ocean circulation system.

Question 12

What is upwelling?

Answer 12

Movement of deep, nutrient-rich water to the surface.

Question 13

What causes a rain shadow?

Answer 13

Dry air descending on the leeward side of a mountain.

Question 14

How does temperature change with elevation?

Answer 14

It decreases by about 6°C for every 1000 meters.

Question 15

What two factors best predict biome type?

Answer 15

Temperature and precipitation.

Question 16

What biome has the highest terrestrial NPP?

Answer 16

Tropical rainforest.

Question 17

What adaptations are common in desert plants?

Answer 17

Drought tolerance or dormancy during dry periods.

Question 18

Why have many temperate grasslands been lost?

Answer 18

Converted to agriculture due to fertile soils.

Question 19

What is the dominant vegetation in the taiga?

Answer 19

Evergreen conifers.

Question 20

What conditions characterize the Arctic tundra?

Answer 20

Low precipitation, permafrost, soggy soils, herbaceous plants.

Question 21

What is the alpine tundra?

Answer 21

A tundra-like biome at high elevations.

Question 22

What is the photic zone?

Answer 22

The sunlit region of a body of water where photosynthesis occurs.

Question 23

What are oligotrophic lakes?

Answer 23

Lakes with low nutrients, clear water, and low algal density.

Question 24

What are eutrophic lakes?

Answer 24

Lakes high in nutrients, with dense algae and possible oxygen depletion.

Question 25

What is eutrophication?

Answer 25

Nutrient enrichment of water leading to algal blooms and oxygen depletion.

Question 26

What causes eutrophication?

Answer 26

Runoff of fertilizers and other nutrients into bodies of water.

Question 27

Why is productivity low in open ocean ecosystems?

Answer 27

Limiting nutrients.

Question 28

Why are continental shelf areas more productive?

Answer 28

Higher nutrient availability.

Question 29

Why are upwelling zones highly productive?

Answer 29

They bring nutrient-rich deep water to the surface.

Question 30

What characterizes the deep sea habitat?

Answer 30

Darkness, cold temperatures, high pressure, low food availability.

Question 31

What is El Niño?

Answer 31

A periodic warming event caused by weakening trade winds, disrupting ocean currents and climate.

Question 32

How does El Niño affect marine ecosystems?

Answer 32

Reduces upwelling, lowering productivity and causing declines in fish, seabirds, and sea lions.

Question 33

How does El Niño affect terrestrial ecosystems?

Answer 33

Changes weather patterns, e.g., wetter in the southeastern U.S., drier in Asia.