Chapter 35 - The Biosphere

Question 1

Define ecology

Answer 1

The study of how organisms interact with their environment

Question 2

What is the order of ecological study?

Answer 2

1. Organism
2. Population
3. Community
4. Ecosystem
5. Landscape
6. Biosphere

Question 3

What is the ultimate source of energy for our planet?

Answer 3

The sun

Question 4

Why is it colder at the poles than the equator?

Answer 4

Since the earth is curved, the equator is more exposed to the sun since it sticks out at it. The poles however do not receive such direct sun rays since they aren’t directly in the pathway of sunlight.

Question 5

What causes seasons?

Answer 5

The tilt of the earth on its axis.

When the Earths axis points towards the sun, it is summer for that hemisphere. When the earths axis points away from the sun, it is winter for that hemisphere.

Question 6

How much does temperature change for every 1000m increase of elevation?

Answer 6

-6°C for every 1000m elevated

Question 7

What is the pelagic zone of marine/freshwater ecosystems? What are its divisions?

Answer 7

Refers to the open water from shore-to-shore.

Divided into:
Photic zone - the depth at which there is enough light for photosynthesis.
Aphotic zone - below the photic zone, where there is little light available.

Question 8

What is the benthic zone of marine/freshwater ecosystems?

Answer 8

Refers to the bottom sediments of the body of water.
This is where you find seaweed, sponges, coral reefs, clams, crabs…etc.

(Note: if near the shore, the benthic zone is in the photic zone)

Question 9

What are the most diverse marine habitats?

Answer 9

Coral reefs

Question 10

What is an estuary?

Answer 10

Where a freshwater stream meets the ocean.

This is an area with ranging salinity since it is both fresh and salt water.

Question 11

How do lakes stratify in the summer? What are the layers called?

Answer 11

Lakes stratifying refers to having warm (less dense) water on top, and cold (dense) water on the bottom.

Warm layer = epilimnion
Cold layer = hypolimnion (think hypothermia)
Layer in between = thermocline

Question 12

What are some benefits of wetlands

Answer 12

• rich is species diversity
• provide water storage during flooding
• filter the water of pollutants before it goes into the lakes

Question 13

What is the most diverse terrestrial habitat?

Answer 13

Tropical rainforest

Question 14

What are the steps to the water cycle?

Answer 14

1. Evaporation and transpiration
2. Condensation in clouds
3. Precipitation onto ocean and land
4. Storage of water in lakes/rivers or in the soil (percolation)
5. Eventually all water flows back into ocean or is evaporated again