Biology: Nutrient Cycles & Population

Question 1

TRUE OR FALSE: Some plants (such as peas and alfalfa) have bacteria living on their roots and they make the soil rich in phosphorus.

Answer 1

FALSE, they make the soil rich in nitrogen.

Question 2

TRUE OR FALSE: The bacteria that turn nitrogen into the form of nitrogen that plants can use are called denitrifying bacteria.

Answer 2

FALSE, Nitrogen-Fixing Bacteria.

Question 3

TRUE OR FALSE: The form that nitrogen must be in for plants to use it is nitrogen dioxide.

Answer 3

FALSE, Nitrate.

Question 4

TRUE OR FALSE: The shells of crabs are made mostly of carbon.

Answer 4

TRUE.

Question 5

TRUE OR FALSE: Water cannot seep down farther than ground water because of the layer of bedrock.

Answer 5

TRUE.

Question 6

TRUE OR FALSE: The three fossil fuels are nitrogen, carbon, and gas.

Answer 6

FALSE, coal, oil, and natural gas.

Question 7

TRUE OR FALSE: Carbon Dioxide is returned to the atmosphere through photosynthesis, burning fossil fuels and burning wood products.

Answer 7

FALSE, cellular respiration NOT photosynthesis.

Question 8

TRUE OR FALSE: The carrying capacity of the Earth is estimated to be about 12 billion people.

Answer 8

TRUE.

Question 9

TRUE OR FALSE: Nitrogen-fixing bacteria and denitrifying bacteria belong to the decomposer group.

Answer 9

FALSE, the BACTERIA group.

Question 10

TRUE OR FALSE: Plants go through photosynthesis while only animals go through cellular respiration.

Answer 10

FALSE, both animals and plants go through cellular respiration.

Question 11

ALL WATER CYCLE TERMS:

Answer 11

1. EVAPORATION
2. CONDENSTATION
3. PRECIPITATION
4. SURFACE RUNOFF
5. ABSORPTION
6. PERCOLATION
7. GROUND WATER
8. TRANSPIRATION
   BEDROCK (don’t forget)

Question 12

Where is Nitrogen found in all cells?

Answer 12

Nitrogen is found in the DNA of all cells.

Question 13

What would happen to the Nitrogen Cycle if all the plants on Earth were gone?

Answer 13

• Nitrates would not be used
• Nitrogen won’t enter food chains
• Nitrogen-fixing bacteria would die
• The whole Nitrogen Cycle would be disrupted.

Question 14

Give the name and definition for the “dotted line.”

Answer 14

Carrying Capacity: The maximum number of population that an ecosystem can sustain.

Question 15

Give two limiting factors against population growth:

Answer 15

• Disease
• # of predators
• Lifespan (if short)

Question 16

Example of parasitism:

Answer 16

Tapeworms on cats and dogs:
- Tapeworms benefit because they have something to feed off of
- Cats and Dogs suffer.

Question 17

Example of a predator-prey relationship:

Answer 17

A fox eating a rabbit.

Question 18

Why don’t predators overpopulate?

Answer 18

• If at any point their population overgrows some will pass away due to the lack of a food source.
• Predators typically have less babies per litter.

Question 19

Why is it important to not pour chemicals down drains or use them on lawns?

Answer 19

• Releases chemicals into the ocean, leading to water pollution.
• Chemicals can harm the plants, affecting the Nitrogen Cycle.

Question 20

Why is it important to talk to plants?

Answer 20

• Gives them carbon dioxide.
• It means that you care about them and/or put the effort into replenishing them everyday.