biology life on earth

Question 1

what is a species

Answer 1

A group of organisms who can interbreed to produce fertile offspring.

Question 2

what is a population

Answer 2

The number of individuals within a species living in a particular area.

Question 2

what is biodiversity

Answer 2

This is the variety of living organisms within an area.

Question 3

what is a producer

Answer 3

An organism that can produce its own food using light energy from the sun.

Question 4

what is a consumer

Answer 4

An organism who has to consume food to gain energy.

Question 5

what is a food web

Answer 5

A diagram to show all of the interlinking food chains within an environment.

Question 5

what is a food chain

Answer 5

Shows the feeding relationship between individuals.

example:
Grasses → Mountain Hare → Golden Eagle

Question 6

whats a community

Answer 6

A community is all of the living organisms living in a particular area.

Question 7

when does competition occur

Answer 7

Competition in ecosystems will occur between organisms when resources are in short supply.

Question 7

what is an ecosystem

Answer 7

An ecosystem consists of all the organisms (the community) living in a particular habitat and the non-living components with which the organisms interact.

Question 8

Describe the interactions of niches between organisms in the environment

Answer 8

A niche is the role an organism plays within a community.

A niche relates to the resource’s organisms require in the ecosystem, such as light and nutrient availability. It can also involve competition, predation and the conditions it can tolerate such as temperature.

Question 9

what are animals in competition for

Answer 9

food
space
water availability
mates

Question 10

what is intraspecific competition

Answer 10

Intraspecific competition occurs from individuals of the same species for all of the resources they require.

Question 11

what is interspecific competition

Answer 11

Interspecific competition occurs from individuals of different species for one or a few of the resources they require.

Question 11

what are plants in competition for

Answer 11

nutrients
water
space
light/sunlight

Question 12

Compare interspecific and intraspecific competition

Answer 12

Intraspecific competition is more intense than interspecific competition because organisms are competing for more resources.

Question 13

what is biotic factors

Answer 13

Biotic factors are living factors which can affect biodiversity in an area.

Question 14

what is abiotic factors

Answer 14

Abiotic factors are non-living factors which can affect biodiversity in an area.

Question 15

examples of abiotic factors

Answer 15

light intensity
soil moisture
pH
temperature

Question 15

examples of biotic factors

Answer 15

competition for resources
disease
grazing
predation

Question 16

light meter limitations and sources of error

Answer 16

accidental covering of the probe, must be taken at the same time of da

Question 17

soil moisture limitations and sources of error

Answer 17

must be placed at the same depth in the ground at each site and wiped clean between readings

Question 17

ph probe limitations and sources of error

Answer 17

must be placed at the same depth and wiped clean between readings

Question 18

temperature limitations and sources of error

Answer 18

thermometer must be held in the same position/depth at every sample point, time must be allowed for the reading to be taken

Question 19

animal sample technique

Answer 19

A pitfall trap is used to measure small invertebrates that live on the ground.

A pot with small holes in the bottom is placed in the ground with the top flush to ground level. It is covered and collected regularly.

Question 20

pitfalll trap sources of error and solutions

Answer 20

A limitation/source of error of this technique is:
Some animals within the trap may eat other captives
Not enough samples taken

How to solve these issues:
Check traps regularly and record
Set up more traps within the sample site

Question 21

plant sample technique

Answer 21

A quadrat is used to sample plants and animals that don’t move. It is a metal/plastic square of varying different sizes. The most common is 1m2.

Question 22

quadrat sources of error

Answer 22

not enough samples taken within the sample site
deliberately ‘choosing’ good spots

Question 23

Biotic antibiotic effects biodiversity

Answer 23

Both biotic and abiotic factors can increase or decrease biodiversity in an area and affect the distribution of organisms.

Question 24

Human influences that impact biodiversity

Answer 24

air pollution
water pollution
habitat destruction by deforestation
desertification
overfishing

Question 25

Describe an indicator species

Answer 25

An indicator species by their presence or absence will indicate environmental quality/levels of pollution in an area.

Question 26

summary equation for photosynthesis

Answer 26

CO2+H20———————>glucose+O2
light energy

Question 27

Describe the light reactions of photosynthesis

Answer 27

During the light reactions, light energy from the sun is trapped by chlorophyll in chloroplasts and is converted into chemical energy which is used to generate ATP.

Water is split to produce Hydrogen and Oxygen. Oxygen diffuses out of the cell.

Question 28

Describe carbon fixation

Answer 28

A series of enzyme-controlled reactions, which use hydrogen and ATP (produced by the light reactions) are combined with carbon dioxide to produce sugar.