Nat 5 - Unit 3

Question 1

Food Chain

Answer 1

The sequence of what eats what in a community

Question 2

Food Web

Answer 2

A network of interrelated food chains

Question 3

Carnivore

Answer 3

An organism that eats animals

Question 4

Herbivore

Answer 4

An organism that eats plants

Question 5

Omnivore

Answer 5

An organism that eats plants and animals

Question 6

Producer

Answer 6

Plants that produce chemical energy, through photosynthesis.
(to produce their own food)

Question 7

Primary consumer

Answer 7

An organism which eats a producer

Question 8

Secondary consumer

Answer 8

An organism which eats primary consumers

Question 9

Tertiary Consumer

Answer 9

An organism which eats secondary consumers

Question 10

Quaternary Consumer

Answer 10

An organism which eats tertiary consumers

Question 11

Predetor

Answer 11

An organism which hunts its food

Question 12

Prey

Answer 12

An organism which is hunted

Question 13

Population

Answer 13

The number of organisms of the same species in an area

Question 14

Community

Answer 14

The number of different species of organisms in an area

A group of interdependant organisms that contain different species

Question 15

Ecosystem

Answer 15

All the organisms (community) living in a particular habitat and all the non-living components (abiotic factors) which affect them.

Question 16

Abiotic

Answer 16

A Non-living factor that can affect organisms

Question 17

Biotic

Answer 17

A living factor that can affect organisms

Question 18

Species

Answer 18

A group of similar species that can interbreed to produce fertile offspring

Question 19

Biodiversity

Answer 19

The variety of species in an area

Question 20

Interspecific competition

Answer 20

occurs when when members of different species compete for the same resources.

Question 21

Intraspecific competition

Answer 21

occurs when members of the same species compete for exactly the same resources

Question 22

Why is intraspecific competition more intense than interspecific competition?

Answer 22

Because in intraspecific competition because the competing organisms have identical needs

Question 23

What do animals compete for

Answer 23

food, shelter, territory, mates

Question 24

What do plants compete for

Answer 24

Light, water, nutrients, space to grow

Question 25

Consumers

Answer 25

Organisms which rely on eating other organisms for their food.

Question 26

Mutation

Answer 26

A random change to genetic material: the only source of new alleles.

Question 27

Natural Selection

Answer 27

The process by which those with favourable alleles (best adapted to the environment), survive and reproduce, passing on their genes.

Question 28

Evolution

Answer 28

A change in the inherited characteristics of a population which overtime through a process of natural selection. Which may result in the formation of a new species.

Question 28

What needs to be present in a population for evolution to occur

Answer 28

Variation within a population

Question 28

Mutations may be..

Answer 28

neutral, advantageous or disadvantageous (to survival)

Question 29

Types of isolating barriers

Answer 29

Ecological, geographical or behavioural

Question 30

Environmental factors which increase the rate of mutation

Answer 30

Radiation and some chemicals

Question 31

When does natural selection occur?

Answer 31

When there are selection pressures

Question 32

New alleles from mutations can result in..

Answer 32

Plants and animals becoming better adapted to their environment

Question 33

Natural Selection occurs when..

Answer 33

1. More offspring are produced than the environment can sustain 2. There are selection pressures 3. Only the best adapted individuals survive to reproduce 4. They pass on their favourable alleles that give the selective advantage 5. These alleles increase in frequency in the population

Question 34

Speciation occurs when...

Answer 34

1. Part of the population becomes isolated by an isolation barrier 2. Different mutations occur in each subpopulation 3. Natural selection selects for different mutations in each group 4. Due to different selection pressures 5. Each sub-population evolves until their genetic differences make them two different species.

Question 35

Show the sequence of antibiotic resistance in bacteria as an example of evolution

Answer 35

Mutation -> use of antibiotic -> natural selection

Question 36

What is Speciation?

Answer 36

The process by which two distinct species evolve from a single original species by natural selection

Question 37

Would the best organism within a species to survive and reproduce be: a) the strongest? b) the one which reproduces the fastest? c) the best adapted to the environment?

Answer 37

c) the best adapted to the environment

Question 38

Why is variation important to the survival of a population?

Answer 38

Because it allows the population to adapt to changing environmental conditions.