Adaptations, Competition and Environmental Change Flashcards
How have animals living in the desert adapted to their environment?
- Many animals have a LARGER SURFACE AREA to lose more body heat which helps to stop them overheating.
- They lose less water by producing small amounts of CONCENTRATED URINE.
- Camels are able to do this by TOLERATING BIG CHANGES IN BODY TEMPERATURE, while kangeroo rats live in burrows under the ground where its cool.
- Desert animals have very THIN LAYERS OF BODY FAT and a thin coat to help them lose body heat (eg camels keep their fat in their hump)
- A SANDY COLOUR gives good CAMOUFLAGE to help avoid predators or sneak up on prey.
How have Artic animals adapted to reduce heat loss?
- Animals have compact (rounded) shape to keep their surface area to a minimum - this reduces heat loss.
- Animals have a thick layer of blubber for insulation and this also acts as an energy store when food is scarce
- Thick hairy coats keep body heat in and greasy fur sheds water (prevents cooling due to evopration)
- Animals have white fur as CAMOUFLAGE to AVOID predators or SNEAK up on prey.
Hpow have desert plants adapted to having little water?
- Plants lose water vapour from the surface of their leaves eg Cacti have spines instead of leaves to reduce water loss.
- They have a smaller surface area compared to their size (about 1000 times smaller surface area than normal plants) which also reduces the water loss
- The plants can have water storage tissue so for example the cactus stores water in its thick stem.
- Some catus have shallow but extensive roots to absorb water quickly over a large area. Others have deep roots to access underground water.
How have plants and animals adapted to deter predators?
- Some plants and animals have armour/external protection - like roses (thorns), cacti (sharp spines) and tortoises (shells).
- Some have positens - bees, poison ivy
- Some have bright warning colours - wasps and bees
- Some microorganisams (bacteria) are known as EXTREMOPHILES as they are adapted to live in extreme conditions like very salty lakes or deep in sea bed where there is hugh water presure.
What resources do plants and animals compete for?
- Plants compete for light, space, water and mineral (nutrients) from the soil.
- Animals need space (territory), food, water and mates. with other species and their own species
What are the living and non living factors that cause change
Living facors:
1. change in the occurance of infectious diseases
- change in number of predators
change in number of prey or availability of food sources - change in the number or types of competitors
Non-living factors:
1. change in average temperature
- change in average rainfall
- change in the level of air and water pollution
Environmental changes affect populations in different ways. What change could result in an increase in population?
If the number of prey increase then there is more food available for predators so they survive and reproduce and their numbers increase
Environmental changes affect populations in different ways. What change could result in a decrease in population size?
Bees in the US are falling rapidly. Experst are not sure why but believe it could be because:
- Some pesticides may be having a negative effect on bees.
- There’s less food available - there aren’t as many nectar-rich plants around any more
- There’s more disease - bees are being killed by new pathogens or parasites.
Environmental changes affect populations in different ways. What change could result in a a change in distribution of population?
A change in distribution means a change in where an organism lives so for example the distribution of bird species in Germany is changing because of a rise in average temperature e.g. the European Bee- Eater bird is a Mediterranean species but its now present in parts of Germany.
How can you use living indicators to measure environmental changes?
- Some organisms are very sensitive to changes in their environment and so can be studied to see effect of human activities - organism known as INDICATOR SPECIES
- Air pollution can be monitored by looking at particular types of LICHEN that are microorganisms that are very sensitive to the concentration of SULPHUR DIOXIDE in the atmosphere. The number and type of LICHEN in a particular location will indicate how clean the air is.
- Raw sewage - bacterial population will increase with more sewage and this uses up the oxygen.
Some invertebrate animals like mayfly larvae are good indicators for water pollution becuase they are sensitive to concentration of dissolved oxygen so more mayfly the cleaner the water.
- Other invertebrate species have adapted to live in polluted conditions so if you see a lot of them you know there is a problem e.g rat-tailed maggots and sludgeworms indicate very high level of water pollution.
How can you use non living indicators to measure environmental changes?
- The use of satellites to measure the temperature of the sea surface and the amount of snow and ice cover.
- Automatic weather stations tell us the atomospheric temperature at various locations. They contain thermometres that are sensitive and accurate.
- They measure rainfall using rain gauges to find out how much the average rainfall changes year on year.
- They use dissolved oxygen meters which measure the concentration of dissolved oxygen in water to discover how the level of water pollution is changing.
In an exam you may be asked to interpret data.
So for example if the data shows a decrease in Lichen what does this mean?
If there is an increase in mayfly larvae in water what does this mean?
If there is an increase in bacteria population in rivers what does this mean?
- Increase in Lichen suggests lower pollution (SULPHATE DIOXIDE) in air so cleaner air.
- Increase in mayfly larvae suggest cleaner water because they are sensitive to increased oxygen
- Increase in bacteria suggest increase in pollution in rivers.
