B1: Adaptations, Competition, Environmental Change and Measuring Environmental Change

Question 1

How are desert animals adapted to their environment?

Answer 1

1. Large surface area to volume ratio to help them lose more body heat to keep cool
2. They produce small amount of concentrated urine and make very little sweat to reduce water loss
3. They have thin layers of body fat and a thin coat to help them lose body heat
4. They usually have a sandy colour, which gives them a good camouflage top avoid predators or sneak up on prey

Question 2

How have arctic animals adapted to reduce heat loss?

Answer 2

1. Small surface area to volume ratio to minimise heat loss
2. They have a thick layer of blubber for insulation and energy storage.
3. They have a thick coat to keep heat in and greasy fur to shed water after swimming which prevents cooling through evaporation
4. Arctic animals have white fur to help avoid predators, or sneak up prey.

Question 3

How are desert plants adapted to having little water?

Answer 3

1. Small surface area to volume ratio to reduce water loss
2. Plants lose water through their leaves so cacti have spikes instead to reduce water loss
3. They have water storage tissues (cacti stores water in its thick stem)
4. The maximise water absorption by having shallow but extensive roots to absorb water quickly. Other plants have deep root to access water far underground.

Question 4

How are some plants and animals adapted to deter predators?

Answer 4

1. Some plants and animals have armour- roses have thorns, cacti have sharp spines and tortoises have shells
2. Others produce poisons like bees and poison ivy
3. Some have warning colours to scar off predators - like wasps.

Question 5

What is an extremophile?

Answer 5

A microorganism that is adapted to live in seriously extreme conditions like volcanic vents, salty lakes and at high pressure on the sea bed.

Question 6

What resources do plants need?

Answer 6

• Light
• Space
• Water
• Minerals from the soil

Question 7

What resources do animals need?

Answer 7

• Space/territory
• Food
• Water
• Mates

Question 8

Define the term ‘competition’.

Answer 8

When organisms compete with other species and members of their own species for the same resources.

Question 9

What living factors cause an environment to change?

Answer 9

1. A change in the occurrence of infectious diseases
2. A change in the number of predators
3. A change in the number of prey or availability of food sources
4. A change in the number of competitors

Question 10

What non-living factors cause an environment to change?

Answer 10

1. A change in average temperature
2. A change in average rainfall
3. A change in the level of air pollution

Question 11

In what ways can environmental changes affect animals and plants?

Answer 11

1. The population size increases (If number of prey increases, more food is available for predators who will be able to survive and reproduce causing their numbers to increase)
2. The population size decreases (the same as above but opposite)
3. The population distribution changes

Question 12

What things can decrease the size of a population?

Answer 12

1. Some pesticides may have a negative affect on animals such as bees
2. There’s less food available
3. There is more disease so more organisms are dying

Question 13

What does a change in distribution mean?

Answer 13

A change in where an organism lives

• Changing temperatures could cause animals to move to cooler/warmer environments
• Lack/more food will cause animals to change where they live.

Question 14

What is an indicator species?

Answer 14

Organisms that are sensitive to changes in the environment and so can be studied to see the effect of human activities.

Question 15

How can air pollution be monitored?

Answer 15

• Some lichens are sensitive to the concentration of sulfur dioxide in the atmosphere
• The number and type of lichen at a particular location will indicate how clean the air is
• The more lichen the cleaner the air in that location

Question 16

How can water pollution be monitored?

Answer 16

• Mayfly larvae are indicators of clean water because they are very sensitive to the concentration of dissolved oxygen in the water.
• If raw sewage has been released in the water, the bacterial population in the water increases and uses up the oxygen so there will be less mayfly larvae in the water
• Other species, such as rat-tailed maggots, are adapted to live in polluted conditions so if there is a large population of them in the water then the water has a high level of pollution

Question 17

What types of non-living indicators are there? What do they do?

Answer 17

1. Satellites- measure temperature of the sea surface and the amount of snow and ice cover
2. Automatic weather stations- measure the atmospheric temperature at various locations
3. Rainfall gauges- find out how much the average rainfall changes year on year.
4. Dissolved oxygen meters- measure the concentration of dissolved oxygen in water to discover how water pollution is changing.

Question 18

What are the advantages of using non-living indicators?

Answer 18

1. Satellites are modern, accurate instruments that give us global coverage
2. Automatic weather stations are sensitive and very accurate- they can measure to very small fractions of a degree
3. Dissolved oxygen meters and rainfall gauges are more accurate than using indicator species.