Ecology

Question 1

Levels in an ecosystem

Answer 1

Habitat - population - community - ecosystem

Question 2

Abiotic factors

7

Answer 2

1. pH of soil and water
2. Oxygen content
3. Salinity of soil and water
4. Temperature
5. Water and food content
6. Light intensity

Question 3

Biotic environment

Answer 3

All the living organisms that an organism interacts with

Question 4

Food chains example

Answer 4

grass - cow - lion

Question 5

Food web example

Answer 5

shrub - aphid - ladybug - spider

shrub - ant - ladybug - spider

Question 6

Trophic levels

Answer 6

Producer (autotrophs) - primary consumer - secondary consumer - tertiary consumer

Question 7

Carbon cycle step 1

Answer 7

During photosynthesis, CO2 is taken in by plants and converted to organic carbon

Question 8

Carbon cycle step 2

Answer 8

During respiration, organisms give out carbon dioxide

Question 9

Carbon cycle step 3

Answer 9

During consumption/ingestion, organic carbon is passed from one organism to another

Question 10

Carbon cycle step 4

Answer 10

When organisms die, decomposition occurs to release carbon dioxide

Question 11

Carbon cycle step 5

Answer 11

During fossilisation, decaying matter is compressed over millions of years to form fossil fuels

Question 12

Carbon cycle step 6

Answer 12

Fossil fuels are mined by factories

Question 13

Carbon cycle step 7

Answer 13

Combustion of fossil fuels release carbon dioxide into the air

Question 14

Carbon cycle step 8

Answer 14

Carbon dioxide may enter the sea via ocean uptake

Question 15

Causes of deforestation

3

Answer 15

1. Human activities
2. Human demand
3. Logging

Question 16

Effects of deforestation

6

Answer 16

1. Loss of habitat
2. Loss of species
3. Soil erosion
4. Flooding
5. Climate change
6. Desertification

Question 17

Solutions to deforestation

3

Answer 17

1. Reforestation
2. Laws
3. Public education

Question 18

Causes of overfishing

3

Answer 18

1. Economic needs
2. Illegal fishing
3. Advancements in fishing technology

Question 19

Effects of overfishing

4

Answer 19

1. Loss of habitat
2. Loss of species
3. Pollution
4. Economic (prices increase)

Question 20

Solutions to overfishing

5

Answer 20

(FECAL)

1. Environmentally friendly fishing gear
2. Eat less seafood
3. Regulate catch size
4. Areas that are protected
5. Laws

Question 21

Causes of eutrophication

Answer 21

1. Waste (faeces) or fertilisers

2. Enter a still body of water (lake)

Question 22

Effects of eutrophication

Answer 22

1. Amount of algae increases (algae bloom)
2. Covers surface of lake and underwater plants cannot receive sunlight
3. Underwater plants cannot photosynthesise and die
4. Amount of oxygen underwater decreases
5. Plants decompose
6. Amount of oxygen further decreases
7. Marine organisms die
8. Algae die

Question 23

Biomagnification

Answer 23

Harmful chemicals get magnified from trophic level to trophic level

Question 24

Bioaccumulation

Answer 24

Accumulation of substances in an organism

Absorbed faster than lost

Question 25

Why doesn’t organic waste get washed out of body

Answer 25

Sneaks past blood-brain barrier, accumulates in tissues, muscles and fats

Question 26

Bio-m/a case study 1

Answer 26

DDT

DDT - water - zooplankton - small fish - large fish - birds

Question 27

Bio-m/a case study 2

Answer 27

Minamata

Organic mercury - water - phytoplankton - small fish - large fish - adults