Minerals And Decay

Question 1

Why are nitrates needed

How are they used

Answer 1

Nitrates are needed to make proteins cell growth

They provide nitrogen for amino acids that form the proteins

Question 2

Why is potassium needed

How is it used

Answer 2

Potassium is used for respiration and photosynthesis

This helps enzymes actions in these processes to speed them up

Question 3

Why are phosphates needed

How are they used

Answer 3

Phosphates are needed for respiration and growth

It provides phosphorus for DNA for genetic code and cell membranes

Question 4

Why is magnesium needed

How is it used

Answer 4

Magnesium is needed for photosynthesis

It makes the chlorophyll molecule for photosynthesis

Question 5

What happens to plants lacking nitrates

Answer 5

Cells don’t grow properly and leaves are yellow

Question 6

What happens to plants lacking potassium

Answer 6

Have under developed fruit/flowers and discoloured leaves

Question 7

What happens to plants lacking phosphates

Answer 7

Under developed roots and discoloured leaves

Question 8

What happens to plants lacking magnesium

Answer 8

Plant unable to make chlorophyll so leaves are yellow

Question 9

Substances are sometimes absorbed against a concentration gradient

What is this called and what does it require

Answer 9

Substances absorbed from a low to high concentration (opposite direction to diffusion) is called ACTIVE TRANSPORT

It requires energy from respiration

Question 10

Decay is..

Answer 10

The breakdown of complex substances into smaller ones by microorganisms

Question 11

How does temperature affect the rate of microorganisms breaking down substances

Answer 11

Microorganisms responsible for decay work at optimum at 40’c

Below this they work slower and above this they denature and cant carry out reactions

Question 12

How does amount of oxygen affect the rate of microorganisms breaking down substances

Answer 12

Microorganism rate of activity increases as oxygen increases

Question 13

How does amount of water affect the rate of microorganisms breaking down substances

Answer 13

Microorganisms prefer moist conditions

With too much water,air spaces in the substrate become waterlogged, reducing oxygen supply and reduces decay rate

Question 14

Why is decay important for plant growth

Answer 14

It releases minerals into the soil for their healthy growth

Other plants can use them

Question 15

Why does storing food in dry, cool conditions prevent microorganisms and fungi from growing on it

Answer 15

When food is exposed to air, moisture and warmth, microorganisms will quickly grow on it

Question 16

What are saprophytes

Give examples

Answer 16

Bacteria and fungi are saprophytes
Feed on dead organic material by secreting enzymes onto their food then absorbing the digested products

Saprophytes are essential for decay

Question 17

What digestion do saprophytes do

Answer 17

Extra-cellular digestion

Question 18

How does canning preserve food

Answer 18

Food heated to destroy microbes and sealed in sterile container to prevent microorganisms getting oxygen

Question 19

How does refrigeration/freezing preserve food

Answer 19

Food kept at low temperatures to slow growth and reproduction of microorganisms

Question 20

How does pickling preserve food

Answer 20

Food pickled in vinegar slows down growth of microorganisms by denaturing their enzymes with low pH

Question 21

How does adding sugar/salt preserve food

Answer 21

Conditions are too concentrated fir microorganisms to survive

Higher solute concentration draws water out of microorganisms’ cells by osmosis, killing them

Question 22

How does drying preserve food

Answer 22

Reduces moisture preventing microorganism growth

Question 23

Detritivores

Give examples

Answer 23

Feed on dead organisms and waste (detritus) produced by living organisms

Earthworms, woodlice and maggots

Question 24

What is detritus

Answer 24

Waste and dead organisms that feeds detritivores

Question 25

How do detritivores speed up the process of decay

How do they work with decomposers

Answer 25

Break down detritus into small particles which have a large surface area making it easier for decomposers to feed on

Also the faeces if detritivores also provide food for decomposers

Question 26

How do humans use decomposer organisms (microorganisms) to break down waste

Answer 26

Feed on human waste in sewage

Break down plant waste in compost

Question 27

Why are fertilisers used

Answer 27

Minerals are found in soil but in low concentrations so fertilisers ensure the plant gets the minerals it needs (nitrates,phosphates,potassium compounds)