The arthropods — questions

1. identify

Which features do all arthropods have? Choose all that apply.

Tick every correct statement.

• Jointed legs
• An exoskeleton
• A segmented body
• Wings
• A backbone
• Six legs

Nudge (only if you are stuck): Think of a beetle, a spider and a centipede: which features do all three share?

2. identify

Match each group of arthropods to the features that place an animal in it.

Write the number of the matching option.

1. Three body parts, three pairs of legs, one pair of antennae
2. Two body parts, four pairs of legs, no antennae
3. More than four pairs of legs, two pairs of antennae
4. A long body of many segments with legs on each, one pair of antennae

• Insects: ______
• Arachnids: ______
• Crustaceans: ______
• Myriapods: ______

Nudge (only if you are stuck): Only one group has no antennae. Only one has two pairs.

3. identify

A garden spider has two body parts, four pairs of legs and no antennae. Next to its mouth are two short feelers. Which group of arthropods is it in?

Circle one answer.

• Insects, because it is small and has jointed legs
• Arachnids, because of its two body parts, four pairs of legs and no antennae
• Crustaceans, because with its feelers it has more than four pairs of legs
• Myriapods, because its legs are long and many

Nudge (only if you are stuck): The short feelers are not legs. Which group has four pairs of legs and no antennae?

4. state

How many legs in total does each of these animals have?

An insect: ______________ unit ________

A spider: ______________ unit ________

A woodlouse: ______________ unit ________

Nudge (only if you are stuck): Count the pairs first, then double. The woodlouse walkthrough in the reading counts one side.

5. identify

A woodlouse lives under logs and stones. Through a hand lens you count seven pairs of legs and two pairs of antennae, one pair tiny. Which statement places it in the right group?

Circle one answer.

• Insect: a small animal that lives under logs and leaves
• Crustacean: more than four pairs of legs and two pairs of antennae
• Myriapod: many legs, one pair under each body plate
• Arachnid: more than three pairs of legs and no wings

Nudge (only if you are stuck): Count the antennae. Which group has two pairs?

6. describe

A pupil says: "A spider is an insect, because it is small and has jointed legs." Give two differences between a spider and an insect that show the pupil is wrong.

Difference 1

Difference 2

Nudge (only if you are stuck): Count three things on each animal: body parts, legs and antennae.

7. identify

A millipede curls into a spiral when touched. It has a long, round body of many segments, with two pairs of short legs on most segments, and one pair of short antennae. Which group of arthropods is it in?

Circle one answer.

• Insects, because it has a pair of antennae
• Crustaceans, because it has more than four pairs of legs
• Myriapods, because of its many segments with legs and one pair of antennae
• Arachnids, because it has more than three pairs of legs

Nudge (only if you are stuck): More than four pairs of legs is not enough on its own. Count the antennae too.

8. identify

Put the three body parts of an insect in order, from the front of the animal to the back.

Write the number of each step in order.

1. Abdomen
2. Head
3. Thorax

• First: ______
• Second: ______
• Last: ______

Nudge (only if you are stuck): The legs are on the middle part.

9. identify

Match each arthropod to its group. You can use a group more than once.

Write the number of the matching option.

1. Insects
2. Arachnids
3. Crustaceans
4. Myriapods

• Scorpion: two body parts, four pairs of legs, a pair of large claws at the front, no antennae: ______
• Crab: a hard shell, five pairs of legs including two large claws, two pairs of antennae: ______
• Centipede: a long, flat body of many segments with one pair of legs on each, one pair of antennae: ______
• Butterfly: three body parts, six legs, two pairs of large wings, one pair of antennae: ______
• Worker ant: no wings, three body parts, six legs, one pair of antennae: ______

Nudge (only if you are stuck): For each one, count body parts, legs and antennae. Wings and claws do not decide the group.

10. deduce / explain

In leaf litter, a pupil finds a small animal with a long, thin body of 15 segments. Each segment has one pair of legs, and it has one pair of antennae. The pupil writes: "It has antennae, so it is an insect." (a) Which group does the animal belong to? (b) Explain why having antennae does not make it an insect. (c) Which feature would you count to check the group?

(a) Group

(b) Why antennae are not enough

(c) Feature to count

Nudge (only if you are stuck): Which groups of arthropods have antennae? How many pairs of legs does an insect have?

11. identify / explain

On a sunny wall, a pupil sees two small black animals running side by side. Both look like ants. Through a hand lens, the first has three body parts, three pairs of legs and one pair of antennae. The second has a narrow waist that makes it look like three parts, but it has two body parts. It has four pairs of legs: it holds the front pair up beside its head and waves them like antennae, and it has no antennae of its own. (a) Name the group of arthropods each animal belongs to. (b) Explain why the second animal is not an insect, even though it looks and moves like an ant.

(a) Group of each animal

(b) Why the second animal is not an insect

Nudge (only if you are stuck): Count the raised front legs as legs. Then count body parts, legs and antennae for each animal.