carbon cycle and water cycle

Question 1

what causes the distribution of organisms

Answer 1

environmental changes

Question 2

what key environmental changes cause a change in the availability of water

Answer 2

• a change in the availability of water
• a change in the temperature
• a change in the composition of atmospheric gases

Question 3

how can a change in the availability of water affect the distribution of species

Answer 3

the distribution of some animal and species change between the wet and dry seasons, the times of year where there is more or less rainfall so there are certain seasons with more or less water available

Question 4

how can a change in temperature affect the distribution of species

Answer 4

a rise in temperature causes species to migrate to areas where its cooler or migrate in higher altitudes where the air is cooler

Question 5

how does a change in the composition of atmospheric gases affect the distribution of species

Answer 5

as air pollution increases the distrubution of species will decrease

Question 6

what are environmental changes caused by

Answer 6

seasonal factors, geographic factors or human interaction

Question 7

stages of the water cycle

Answer 7

1) energy from the sun causes the water to evaporate from the surface of the sea, turning it into water vapour
2) water also evaporates from the plants known as transpiration
3) the warm water vapour travels into the air and cools down and when it cools the water vapour condenses to form clouds
4) the water in the clouds then falls to the ground as precipitation
5) once the water hits the ground some of it evaporates back into the atmosphere as water vapour, some of the water passes through rocks and form aquifers whilst others provide freshwater for plants and animals
6) it then drains into the sea before the whole process starts again

Question 8

how plants play a role in the water cycle

Answer 8

1) plants take up water in their roots
2) the water then moves up the plant in the xylem and passes out of the leaves through stomata as water vapour (this is transpiration)

Question 9

how do animals take part in the water cycle

Answer 9

1) they take in water through drinking and in their food
2) they release water in their urine, faeces and when they exhale

Question 10

what transpiration

Answer 10

when water evaporates from the plants

Question 11

whats precipitation

Answer 11

when rain, snow, hail and sleet fall from the sky

Question 12

whats percolation

Answer 12

the movement of water through the soil itself.

Question 13

what are living things made out of

Answer 13

materials they take from the world around them

Question 14

where do the materials that make up living things go

Answer 14

they get passed up the food chain and then are returned to the environment as waste products or are decayed when an organism dies

Question 15

why do materials decay

Answer 15

as they are broken down by microorganisms

Question 16

how can you increase the rate of decay and why

Answer 16

in warm, moist aerobic conditions as the microorganism are more active in these conditions

Question 17

what does decay do

Answer 17

it puts the stuff that plants need to grow back into the soil

Question 18

what happens to the materials in a stable community

Answer 18

the materials that are taken out of the soul and used by plants are put back in

Question 19

how does plants release carbon into the air

Answer 19

1) CO2 is removed from the atmosphere by green plants and algae during photosynthesis, the carbon is used to make glucose which can be tuned in to make carbohydrates, fats and proteins that make up the bodies of plants and algae
2) when the plants and algae respire some carbon is returned to the atmosphere as CO2
3) when the plants and algae are eaten by animals some carbon becomes part of the fats and proteins in their bodies, the carbon then moves through the food chain
4) when plants, algae and animals die detritus feeders and microorganisms feed on their remains, and when these organisms respire CO2 is returned to the atmosphere

Question 20

how do animals release C02 into the atmosphere

Answer 20

5) when the animals respire some carbon is returned to the atmosphere as CO2
6) when plants, algae and animals die detritus feeders and microorganisms feed on their remains, and when these organisms respire CO2 is returned to the atmosphere
7) animals also produce waste that is broken down by detritus feeders and microorganisms

Question 21

how do fossil fuels release CO2 into the atmosphere

Answer 21

7) the combustion of wood and fossil fuels also release CO2 back into the air

Question 22

how does carbon enter the carbon cycle

Answer 22

by photosynthesis

Question 23

stages f the carbon cycles

Answer 23

1) CO2 is removed from the atmosphere by green plants and algae during photosynthesis, the carbon is used to make glucose which can be tuned in to make carbohydrates, fats and proteins that make up the bodies of plants and algae
2) when the plants and algae respire some carbon is returned to the atmosphere as CO2
3) when the plants and algae are eaten by animals some carbon becomes part of the fats and proteins in their bodies, the carbon then moves through the food chain
4) when the animals respire some carbon is returned to the atmosphere as CO2
5) when plants, algae and animals die detritus feeders and microorganisms feed on their remains, and when these organisms respire CO2 is returned to the atmosphere
6) animals also produce waste that is broken down by detritus feeders and microorganisms
7) the decomposers release mineral ions into the soil and under certain conditions the decomposers cannot function properly so the carbon in the dead remains are slowly converted to fossil fuels, causing the carbon to be trapped in the ground
8) the combustion of fossil fuels and wood caused carbon dioxide to be released into the atmosphere

Question 24

what is compost

Answer 24

a decomposed organic matter that is used as a neutral fertiliser for crops and garden plants

Question 25

what factors is rate of decay affected by

Answer 25

• temperature
• oxygen availability
• water availability
• number of decay

Question 26

why does temperature affect the rate of decay

Answer 26

• warmer temperatures make things decompose quicker as they increase the rate of enzymes
• if its too hot or too cold decomposition slows down or stops as the enzymes denature causing the organism to die

Question 27

why does temperature affect the rate of decay

Answer 27

• warmer temperatures make things decompose quicker as they increase the rate of enzymes
• if its too hot or too cold decomposition slows down or stops as the enzymes denature causing the organism to die

Question 28

how does oxygen availability affect the rate of decomposition

Answer 28

As the volume of available oxygen increases, the rate of decomposition also increases as Oxygen is needed for many decomposers to respire, to enable them to grow and multiply, however some decomposers can survive in anaerobic conditions

Question 29

how does water availability affect rate of decomposition

Answer 29

decay takes place faster in moist conditions as the organisms involved in decay need water to carry out the biological processes

Question 30

how does water availability affect rate of decomposition

Answer 30

decay takes place faster in moist conditions as the organisms involved in decay need water to carry out the biological processes

Question 31

how does the number of decay organisms affect rate of decomposition

Answer 31

the more microorganisms and detritus feeders the faster decomposition

Question 32

how is biogas made

Answer 32

made by anaerobic decay of waste materials in a simple fermenter called a biogas generator

Question 33

what is biogas made up of

Answer 33

methane

Question 34

how is biogas made

Answer 34

• the anaerobic decay of plants and animal waste
• sludge waste from sewage works or sugar factories makes biogas on a large scale

Question 35

why do biogases have to be used straight away

Answer 35

as it cant be stored as a liquid as it would require a high pressure

Question 36

what is biogas used for

Answer 36

• heating
• cooking
• lighting
• generate electricity

Question 37

what are the two main types of biogas generators

Answer 37

• batch generators
• continuous generators

Question 38

what do batch generators do

Answer 38

• batch generators makes biogas in small batches, by being manually loaded with waste and this is left to digest and the by products are cleared away at the end of each session

Question 39

what are continuous generators

Answer 39

• this makes biogas all the time by water being continuously fed in so the biogas is produced at a steady rate, these are suited for large scale biogas projects

Question 40

what do biogas generators need

Answer 40

• an inlet for waste materials to be put in
• an outlet for the digested material to be removed through
• an outlet so the biogas can be piped to where it is needed

Question 41

REQUIRED PRACTICAL for the effect of temperature on the rate of decay of fresh milk by measuring pH

Answer 41

1) label a test tube lipase and then use a pipette to place 5cm3 of lipase solution into the test tube
2) label another test tube milk and add 5 drops of phenolphthalein into the test tube
3) add 5cm3 of milk into the test tube labelled milk and 7cm3 of sodium carbonate into the same test tube, this causes the solution into the tube alkaline as sodium carbonate is alkaline and so the solution should be pink
4) then place both of the test tubes into a water bath set to 30 degrees and leave them to reach the temperature of the water bath, by placing a thermometer into the test tube containing the milk to check the temperature
5) once the tubes have reached 30 degrees we use a pipette to put 1cm3 of the lipase solution into the test tube containing mil and start a stopwatch straight away
6) stir the solution with a glass rod and at this point the enzyme lipase will start to break down fat molecules in the milk, releasing fatty acids causing the solution to become acidic
7) as soon as the solution loses its pink colour, stop the stopwatch and record how long the colour change took in a table
8) repeat the experiment with a range of different temperatures

Question 42

why does milk go sour when left in room temperature

Answer 42

as the bacteria in the milk start the decay process by using enzymes to produce acidic molecules, causing the sour milk to taste acidic

Question 43

problems of REQUIRED PRACTICAL for the effect of temperature on the rate of decay of fresh milk by measuring pH

Answer 43

• decay is a very slow process so its hard to observe in a lesson
• we have to use a clean test tube for milk in each experiment
• as we are looking for a change of colour it can be difficult to decide the exact point to stop the timer

Question 44

whats the different variables for the REQUIRED PRACTICAL for the effect of temperature on the rate of decay of fresh milk by measuring pH

Answer 44

• independent - temperature
• dependent - time taken for the milk solution to turn colourless
• control - the volumes of the different solutions

Question 45

why should we use a clean test tube for the milk solution for each experiment REQUIRED PRACTICAL

Answer 45

any trace of lipase from previous experiments will trigger the reaction before we are ready