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Flashcards in Unit 2 Deck (62)
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1
Q

What is a habitat

A

Where an organism lives

2
Q

What is a population

A

Total number of one type of organism in an ecosystem

3
Q

What is a community

A

All the living things in an ecosystem

4
Q

What is an ecosystem

A

Interaction between living and non-living parts of ecosystem(habitats and communities)

5
Q

What is biodiversity

A

The range of species which exists within am ecosystem

6
Q

What is a species

A

A group of organisms that are so similar to one another genetically that they are able to interbreed and produce fertile offspring

7
Q

What is an abiotic factor

A

Abiotic factors are non living or physical factors that affect organisms e.g. light intensity, pH, temperature

8
Q

What is a biotic factor

A

Biotic factors are related to living things e.g. competition for food space or light etc.

9
Q

What is predation

A

Predation is the eating of one organism by another

10
Q

What is a niche

A

A niche is a role that an organism plays within a community . It relates to the resources it requires in its ecosystem,such as light and nutrient availability

11
Q

What is a producer

A

Green plants able to make their own food by photosynthesis

12
Q

What is a consumer

A

An animal which get their energy by feeding on plants or animals

13
Q

What is a herbivore

A

Animal which only feeds on plants

14
Q

What is carnivore

A

Animal that only eats meat

15
Q

What is an omnivore

A

Animal which feeds on both plants and animals

16
Q

What is a prey

A

The animal eaten by the predator

17
Q

What is decomposer

A

Bacteria and fungi, which breakdown organic matter

18
Q

What is a food chain

A

A relationship where one organism feeds on the previous one in a series and in turn provides food for the next one

19
Q

What is a food web

A

Several inter-connecting food chains

20
Q

When does competition in an ecosystem occur

A

When resources are in short supply

21
Q

What is interspecific competition

A

It occurs amongst most individuals of different species for one or a few of the resources they require

22
Q

What is intraspecific competition

A

It occurs amongst individuals of the same species and is for all resources they require, it is more intense that interspecific competition

23
Q

What is an adaption

A

When organisms, which occupy different niches, have special features that allow them to survive in their habitats

24
Q

Name 2 examples of sampling techniques

A

Pitfall trap and quadrat

25
Q

What is a pitfall trap used for

A

A pitfall trap is used to sample organism that move around in the leaf litter

26
Q

What is a quadrat used for

A

A quadrat is used to sample plants and animals that do not move around much

27
Q

What is used to measure light intensity

A

A light meter

28
Q

What is used to measure soil moisture

A

A moisture meter

29
Q

What is an indicator species

A

Indicator species are species that by their presence or absence indicate the environmental quality/level of pollution

30
Q

Name 2 biological keys

A

A paired statement key and a branched key

31
Q

What is the name of the pores in leaves

A

Stomata

32
Q

What are the 2 stages of photosynthesis

A

Light reactions and carbon fixation

33
Q

Where is the sight of photosynthesis

A

The chloroplast

34
Q

Explain stage 1 of photosynthesis (light dependent stage)

A

Light energy from the sun is absorbed by chlorophyll in chloroplast and used to: convert light energy into chemical energy, generate ATP, split water (Called photosythilis)

35
Q

Why is water split in photosynthesis

A

To release oxygen gas that diffuses from the cell as a by-product, also to release hydrogen

36
Q

Explain stage 2 of photosynthesis (carbon fixation )

A

Carbon fixation is a series of enzyme controlled reactions, which use hydrogen and ATP, produced by the light reactions with carbon dioxide to produce a sugar, called glucose

37
Q

What is the word equation did photosynthesis

A

Light energy

Carbon dioxide + water ————> glucose + oxygen Chlorophyll

38
Q

What are limiting factors

A

These are factors which if in short supply restrict the rate of photosynthesis and plant growth

39
Q

Name 3 limiting factors

A

Light intensity, carbon dioxide concentration, temperature

40
Q

Arrows in a food chain show what?

A

The direction of energy flow

41
Q

Name 3 producers

A

Daisies, grass, dandelions

42
Q

What does a food chain always start with

A

A plant

43
Q

What is a primary consumer

A

First consumer in a food chain

44
Q

What is a secondary consumer

A

The second Consumer in a food chain

45
Q

What is a tertiary consumer

A

The third consumer in a food chain

46
Q

What is the majority of energy lost as in energy transfer

A

Heat

47
Q

Only a very small quantity Of what is used for growth in energy transfer

A

Energy

48
Q

What is a pyramid of numbers

A

A diagram that represents the number of organisms at each stage in a food chain

49
Q

What is a pyramid of energy

A

A diagram that shows the available energy stored in the biomass of organisms at each stage of a food chain

50
Q

Name 3 developments in agriculture

A

Increased use of pesticide to kill predators, which attack crops. Increased use of herbacide to kill weeds, which compete with crops for resource. Developing genetically modified crops

51
Q

What is a control experiment

A

Can be compared to the experiment to prove that the one variable being changed has caused the result

52
Q

What happens to nitrated dissolved in soil water

A

They are absorbed into plants

53
Q

Describe the algal bloom process

A

Fertilisers dissolve in rainwater and leech from the soul into the freshwater, adding unwanted nitrate, the extra nitrate increases populations which creates algal bloom, algae blooms reduce light levels killing aquatic plants, dead plants become food for bacteria , the bacteria use up large quantities of oxygen for other organisms . As a result many animals die (biodiversity decreases)

54
Q

What is herbicide used to kill

A

Weeds

55
Q

Name 3 bad effects of pesticides

A

Kills other species, as the toxic molecules pass along the food chain the concentration increases, pesticides toxicity increases and can reach lethal levels

56
Q

What is biological control

A

Uses pests’ natural enemies against them

57
Q

What is a mutation

A

A mutation is a random change to the DNA that occurs rarely

58
Q

What is a mutagenic agent

A

Something that increases the rate of mutation

59
Q

What is a isolating barrier

A

An isolation barrier splits a population, it can be geographical, ecological or reproductive

60
Q

What is speciation

A

The formation of a new species

61
Q

How do you improve results when using a light meter

A

Don’t cast a shadow

62
Q

How to improve results when using a moisture meter

A

Always dry the probe