ecosystems

Question 1

what is a fertiliser

Answer 1

A fertiliser is a substance that is applied to soil, in order to supply plants with nutrients.

Question 2

why do we need fertilisers

Answer 2

fertilisers are added to soils to replace lost nutrients.

Question 3

how are nutrients lists from the soil?

Answer 3

When crops are harvested
when livestock are removed

Question 4

3 main compounds in fertilisers

Answer 4

nitrogen potassium phosphorus

Question 5

what’s leaching

Answer 5

dissolved ions flow through the soil into bodies of water

Question 6

bad thing about leaching

Answer 6

often wash into waterways such as rivers and ponds, and this can result in eutrophication

Question 7

what is eutrophication

Answer 7

death of aquatic life caused by increased nitrate levels in water from fertilisers

Question 8

what happens when the plants below die

Answer 8

decomposers use oxygen to aerobically respire, so as the number of decomposers increases the oxygen in the water is depleted.- kills fish

Question 9

what’s a biotic factor

Answer 9

any living factor that affects another organism

Question 10

examples of biotic factors

Answer 10

competition for food
competition for territory
amount of disease
mates

Question 11

what’s an abiotic factor

Answer 11

non living parts of the environment that can affect other organisms

Question 12

examples of abiotic factors

Answer 12

light intensity
humidity
pH and mineral content if soil
Co2 conc
temperature

Question 13

what happens when temp increases? for plants

Answer 13

inc rate of photosynthesis
enzymes work faster
inc rate of plant growth

Question 14

what happens when temp increases? for animals

Answer 14

use less energy keeping warm
more energy for growth

Question 15

what is abundance

Answer 15

how many organisms there are

Question 16

what’s distribution

Answer 16

where the organisms are

Question 17

what’s sampling

Answer 17

only measuring a subset of the organisms, and use that subset to make predictions about the whole population.

Question 18

what are quadrants and what are they for?

Answer 18

square frames, that have been subdivided into lots of smaller squares. measure the abundance

Question 19

what are transects and what are they for

Answer 19

A line through a habitat along which organisms are sampled - measure the change in distribution

Question 20

why do we use subsets?

Answer 20

it would be impossible, or very time consuming, to count all the organisms

Question 21

what are producers

Answer 21

Organisms at the very start of a food chain that can create glucose using photosynthesis

Question 22

what’s a predator (not drake)

Answer 22

An animal that hunts and kills other animals for food

Question 23

what’s prey

Answer 23

An organism that is killed and eaten by a predator

Question 24

What does each bar in a pyramid of biomass show?

Answer 24

The biomass of all organisms in that trophic level

Question 25

why is only 10% if energy transferred?

Answer 25

Organisms don’t normally eat every part of their food
Some of the material they eat may not be absorbed
energy that is absorbed is used to release energy (via respiration) for movement

Question 26

what is biodiversity

Answer 26

The variety of living things on earth, or within a particular ecosystem

Question 27

why is biodiversity important

Answer 27

It increases the stability of the ecosystem, so that changes are less likely to have adverse affects
Many of our medicinal drugs come from wild species

Question 28

what’s ecology

Answer 28

Ecology is the study of the relationships between living organisms and their physical environment.

Question 29

what’s a habitat

Answer 29

where an organism lives

Question 30

what’s a population

Answer 30

all the organisms of a particular species that live in the same habitat.

Question 31

what’s a community

Answer 31

All the populations of different species that live together in a habitat

Question 32

what’s an ecosystem

Answer 32

the interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of their environment.

Question 33

what’s competition

Answer 33

interaction between organisms or species in which they both try to use the same limited resources.

Question 34

Give three resources that plants compete for.

Answer 34

water
light
space

Question 35

Give three resources that animals compete for.

Answer 35

food water mates territory

Question 36

steps of eutrophication

Answer 36

1.akgae griw fast using up lots of oxygen and blocking sunlight
2. aquatic plants begin to die bc of fertiliser run off
3. dead matter provides food for microbes
4. increase competition for oxygen
5. water becomes deoxygenated
6. fish die

Question 37

what causes the fertiliser run off

Answer 37

farmers use too much
applying it just before heavy rainfall

Question 38

factors that affect decomposition

Answer 38

temp , moisture
cold slows decay, hot prevents bacterial activity (breaks down active sites denatures enzymes)
if there’s no chemical reaction there’s no energy