Characteristics and Classification of Living Organisms

8 questions, 55 marks, every one with its mark scheme, 3 of them Higher Tier or Extended only.

Or open them one at a time, as you finish each question.

Question 1

6 marks

A student watches a desert hedgehog in a wildlife park over several months.

1(a)[2 marks]

The student lists some observations of the hedgehog.

Which two observations describe characteristics of all living organisms?

Tick (✓) two boxes.

It has spines on its back
It removes carbon dioxide produced in its cells
It sleeps during the day
Its dry mass increases permanently as it gets older
It lives in a burrow

Mark scheme

It removes carbon dioxide produced in its cells1
Its dry mass increases permanently as it gets older1

1(b)[2 marks]

The hedgehog rolls into a ball when it hears a loud noise. This is an example of sensitivity.

State what is meant by the term sensitivity.

Mark scheme

the ability to detect stimuli in the internal or external environment1
and make appropriate responses1

1(c)[2 marks]

Define excretion.

Mark scheme

removal of waste products of metabolism1
and substances in excess of requirements1

Question 2

4 marks

Three species of gazelle that live in dry grassland and desert are:

Gazella dorcas
Gazella subgutturosa
Nanger dama

2(a)[1 mark]

State the genus of the goitered gazelle, Gazella subgutturosa.

Mark scheme

Gazella1

2(b)[1 mark]

State what the second word of the name Nanger dama represents.

Mark scheme

species1

2(c)[2 marks]

Define the term species.

Mark scheme

a group of organisms that can reproduce1
to produce fertile offspring1

Question 3

5 marks

A diver records four species of fish, P, Q, R and S, on a coral reef. The table shows some of their features.

Fish	Spines on back	Stripes on body	Barbels under mouth
P	present	present	absent
Q	present	absent	absent
R	absent	absent	present
S	absent	present	absent

3(a)[3 marks]

Complete the dichotomous key to identify the four fish.

Step	Statement	Go to
1a	has spines on back	go to 2
1b	spines on back absent	go to 3
2a		P
2b	stripes on body absent	Q
3a	has barbels under mouth
3b		S

Mark scheme

has stripes on body1
R1
barbels under mouth absent1

3(b)[2 marks]

The diver then records a fifth species, fish T. Fish T has no spines on its back, no stripes on its body and no barbels under its mouth.

Using the key, fish T would be identified as fish S.

Suggest how the key could be changed so that it separates fish T from fish S.

Mark scheme

add a new step after 3b1
with the statements has stripes on body and stripes on body absent1

Question 4

10 marks

A pond in a nature reserve contains many different organisms.

4(a)[3 marks]

Duckweed and water snails both live in the pond.

State three features of organisms in the plant kingdom that are not features of organisms in the animal kingdom.

Mark scheme

cellulose cell wall1
chloroplasts containing chlorophyll1
large permanent vacuole1

4(b)[4 marks]

The table shows four vertebrates seen at the pond.

Complete the table.

Animal	Vertebrate group	Body covering
heron	birds
water vole		fur
carp	fish
grass snake	reptiles

Mark scheme

feathers1
mammals1
scales1
dry scaly skin1

4(c)[3 marks]

Newts are amphibians that live in and around the pond.

State three features of amphibians that are not features of reptiles.

Mark scheme

Any 3 from:

moist skin1
eggs laid in water1
larvae have gills and adults have lungs1
gas exchange through skin1

Question 5

5 marks

A student collects small animals from leaf litter and from a rock pool. All of the animals are arthropods.

5(a)[2 marks]

State two features shared by all arthropods.

Mark scheme

Any 2 from:

exoskeleton1
segmented body1
jointed legs1

5(b)[1 mark]

One arthropod from the rock pool has two pairs of antennae and gills.

Name the group of arthropods it belongs to.

Mark scheme

crustaceans1

5(c)[2 marks]

One arthropod from the leaf litter has wings.

Describe two other features that would show that this arthropod is an insect.

Mark scheme

Any 2 from:

three body regions: head, thorax and abdomen1
three pairs of legs1
one pair of antennae1

Question 6

Extended7 marks

The table describes four organisms, A, B, C and D, found in a sample of soil.

Organism	Description
A	single cell; no nucleus; circular DNA and plasmids
B	body made of hyphae; cells have a nucleus; cell wall not made of cellulose
C	single cell; has a nucleus and chloroplasts
D	multicellular; no cell wall; no chloroplasts

6(a)[3 marks]

Complete the table to name the kingdom of each organism.

Organism	Kingdom
A
B
C
D	animal

Mark scheme

prokaryote1
fungus1
protoctist1

6(b)[2 marks]

State two features of organism C, other than a nucleus, that organism A does not have.

Mark scheme

Any 2 from:

membrane-bound organelles1
linear chromosomes1
chloroplasts1

6(c)[1 mark]

Give one feature from the table which shows that organism C is not a plant.

Mark scheme

it is a single cell1

6(d)[1 mark]

Some of the organisms in the soil are infected by viruses.

Name the structure that surrounds the genetic material of a virus.

Mark scheme

protein coat1

Question 7

Extended10 marks

A student finds two flowering plants, E and F, growing on waste ground.

Plant E has broad leaves, each joined to the stem by a petiole. Its flowers each have ten petals.

Plant F has narrow leaves. Its flowers each have six petals.

7(a)[3 marks]

Plants are divided into ferns and flowering plants.

State three structures produced by flowering plants that are not produced by ferns.

Mark scheme

Any 3 from:

flowers1
pollen1
ovules1
seeds1
fruit1

7(b)[3 marks]

State which plant, E or F, is a dicotyledon.

Give two reasons from the description for your answer.

Mark scheme

E1
broad leaves with a petiole1
flower parts in multiples of five1

7(c)[4 marks]

Complete the table to compare monocotyledons and dicotyledons.

Feature	Monocotyledons	Dicotyledons
Seed leaves	one cotyledon
Veins in leaves
Vascular bundles in the stem		in a ring

Mark scheme

two cotyledons1
parallel veins1
network of veins1
throughout the stem1

Question 8

Extended8 marks

Scientists discovered a new species of gecko, W, on an island. They compared the base sequence of one gene in species W with the same gene in four known gecko species, J, K, L and M.

The table shows the number of differences between the base sequence of each species and that of species W.

Species	Number of differences from species W
J	46
K	9
L	31
M	58

8(a)[2 marks]

State which species, J, K, L or M, is most closely related to species W.

Give a reason for your answer.

Mark scheme

K1
fewest differences in base sequence1

8(b)[1 mark]

A classification diagram is drawn for the five gecko species.

State which species has the branch that splits off earliest from the branch leading to species W.

Mark scheme

8(c)[5 marks]

Describe how scientists use DNA to classify a newly discovered species, and how the results show which species are most closely related.

Mark scheme

Any 5 from:

use extracted DNA1
determine the base sequences1
compare them with other known species1
more similar base sequences have fewer differences1
groups that share a more recent common ancestor are more closely related1
classification systems aim to reflect evolutionary relationships1
DNA data is more accurate and not subjective1

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