Harnessing Biology Flashcards by ella bates

What is selective breeding?

adapting an animals biological characteristics during breeding

How well did you know this?

Not at all

Perfectly

Why does selective breeding happen?

to create animals with desired characteristics

How well did you know this?

Not at all

Perfectly

How does selective breeding work?

-choose desired feature
-breed organism with that feature
-only select offspring with desired feature
-repeat

How well did you know this?

Not at all

Perfectly

What is the aim of selectively breeding crops?

-give higher yields
-resistant to certain diseases
-resistant to pests
-better balance of nutrients

How well did you know this?

Not at all

Perfectly

What features of animals are selectively bred?

-produce more meat, milk, eggs
-produce more/ better quality fur
-produce more offspring
-increased resistance to diseases and parasites

How well did you know this?

Not at all

Perfectly

What factors do farmers attempt to control to maximise crop yield?

-light intensity
-CO2 conc
-temperature

How well did you know this?

Not at all

Perfectly

What features of a greenhouse are useful for farmers?

-artificial heating
-artificial lighting
-artificial CO2 in air
-regular watering

How well did you know this?

Not at all

Perfectly

Greenhouses and polythene tunnels provide enhanced…

conditions for plants to grow

How well did you know this?

Not at all

Perfectly

GREENHOUSES: Why is it made out of glass?

-transparent
-allows natural light for photosynthesis

How well did you know this?

Not at all

Perfectly

GREENHOUSES: Why is it a benefit that they can be heated easily?

increases enzyme activity

How well did you know this?

Not at all

Perfectly

GREENHOUSES: What is the benefit of burning fossil fuels as a heating method?

-conc of CO2 and water vapour increase
-both factors needed for photosynthesis
-also reduces water loss from plant through transpiration

How well did you know this?

Not at all

Perfectly

5 ways to increase crop yield

use of fertilisers
leguminous crops
ploughing fields
controlling soil pH
controlling CO2, light + heat

How well did you know this?

Not at all

Perfectly

What do fertilisers provide for crops?

elements to grow - e.g. nitrates for proteins, magnesium for chlorophyll

How well did you know this?

Not at all

Perfectly

What are organic fertilisers?

made from faces of farm animals (manure) mixed with straw

How well did you know this?

Not at all

Perfectly

What are inorganic fertilisers?

inorganic compounds, such as potassium nitrates or ammonium nitrates in specific amounts for optimum yield production

How well did you know this?

Not at all

Perfectly

What are ADVANTAGES of organic fertilisers?

-improves soil structure
-greater range of minerals
-less cost for farmer

How well did you know this?

Not at all

Perfectly

What are the ADVANTAGES of inorganic fertilisers?

-mineral ions release immediately (FAST ACTING)
-contents known
-easy to apply

How well did you know this?

Not at all

Perfectly

What are the DISADVANTAGES of organic fertilisers?

-slow acting
-may contain pests
-bulkier, more difficult to apply

How well did you know this?

Not at all

Perfectly

What are the DISADVANTAGES of inorganic fertilisers?

-can lead to eutrophication (as fertiliser is soluble)
-requires regular reapplication

How well did you know this?

Not at all

Perfectly

What do leguminous crops have in their root nodules?

nitrogen-fixing bacteria

How well did you know this?

Not at all

Perfectly

How do leguminous crops increase crop yield?

-converts nitrogen gas into ammonium
-releases ammonium into soil

How well did you know this?

Not at all

Perfectly

What are pests?

organisms that reduce the yield of crops or stock animals

How well did you know this?

Not at all

Perfectly

2 ways to control pests

-use pesticides
-biological control (using another organism to reduce number of pests)

How well did you know this?

Not at all

Perfectly

What pesticide kills plant pests?

herbicides

How well did you know this?

Not at all

Perfectly

What pesticide kills insects?

insecticides

What pesticide kills fungi?

fungicides

What pesticide kills molluscs (slugs, snails)?

molluscicides

Pesticides help improve the...

yield from crops and livestock

Biological control NEVER...

eradicates a pest

Yeast respires...

anaerobically

What is the word equation for anaerobic respiration?

glucose ---> ethanol + carbon dioxide

How does bread rise?

bubbles of carbon dioxide gas expand the dough

Does ethanol remain in bread after baking?

NO - due to high temperatures during bread making ethanol is evaporated

How can we investigate the rate of anaerobic respiration?

production of carbon dioxide

2 ways to test for carbon dioxide

-limewater (turns cloudy) -hydrogen carbonate (yellow high conc, purple low conc)

PRACTICAL: Testing for rate of anaerobic respiration

-dissolve sugar in boiled water -add yeast and mix -add a layer of vegetable oil -connect a delivery tube to a second boiling tube containing hydrogen carbonate indicator

PRACTICAL: What is the function of the layer of vegetable oil?

prevents oxygen entering (ensuring anaerobic respiration takes place)

What fungus produces the antibiotic penicillin?

Pencillium

Bacteria can be genetically engineered to produce...

human insulin

What bacteria is used in yoghurt prodcution?

Lactobacillus

Why is milk initially pasteurised?

to kill bacteria

What temperature is Lactobacillus maintained at?

46C

How does Lactobacillus respire and what are the products?

anaerobically to produce lactic acid

What temperature is yoghurt cooled to after production and why?

-5C -helps preserve the yoghurt

What do farmers feed their fish?

-high lipid and protein food -promotes rapid growth

How often do farmers feed their fish?

-regularly -in small amounts

What is the problem of putting multiple species in one pond?

-interspecific competition (competition for food causing species to be wiped out)

What is Predation?

carnivorous species preying on other fish

How can Predation be solved?

place different species in different ponds, tanks etc

What is intraspecific competition?

when larger individuals out-compete small individuals for food/ larger individuals feed on smaller individuals

How do fish farms affect the environment?

-can reduce biodiversity (as some fish escape and out-compete others) -parasites or pathogens can be introduced into ecosystems by farmed fish -eutrophication + reduction in oxygen conc of water

Biodiversity def

the measure of how many different species live in an ecosystem

Effects of deforestation: Leaching

-mineral ions removed from soil -can lead to eutrophication

Effects of deforestation: soil erosion

reduces chances of plants re-growing

Effects of deforestation: evapotranspiration

breaks cycle of transpiration - can lead to droughts

Fertilisers normally contain...

nitrates and phosphates

Fertilisers are extremely soluble in...

water

Eutrophication (step by step)

1. fertilisers run off into rivers 2. nitrates (in fertilisers) are absorbed by algae on top of river 3. algal bloom (completely covers surface of water) 4.blocks sunlight for other plants in river 5. other plants die (as cannot photosynthesise) 6. the algae dies 7. bacteria multiplies and grows (feeding from dead plants) 8. bacteria uses up oxygen in water 9. decreases oxygen levels of water 10. increases death of other organism (e.g. fish)

What is sewage?

undigested food material

Sewage provides a good source of food for...

bacteria to grow and multiply

What is beer made from?

barley

What does barley contain?

-starch -starch is broken down into glucose -glucose id fermented by yeast

How is wine made?

yeast is used to ferment sugars in grape juice

What is biotechnology?

using any organism to make products that are useful to humans

The inside of a fermenter tank must be...

sterilised

Why must the inside of a fermented tank be sterilised?

prevents product becoming contaminated by other microorganisms

What is an aseptic technique?

method to prevent contamination by unwanted organisms

Aseptic technique example

-filtering the air -sterilising fermenter with steam