Year 4 Science: Using a key for animals
Part of the Year 4 Science classification keys chapter. Chapter overview · whole chapter on one page
Using a key for animals
This is the animal key. Start at step 1. Answer each question yes or no, then follow the arrow: go to step a number, or read the name.
| Step | Question | If yes | If no |
|---|---|---|---|
| 1 | Does it have a backbone? | go to step 2 | go to step 6 |
| 2 | Does it have feathers? | bird | go to step 3 |
| 3 | Does it live in water and have fins? | fish | go to step 4 |
| 4 | Does it have fur or hair? | mammal | go to step 5 |
| 5 | Does it have dry, scaly skin? | reptile | amphibian |
| 6 | Does it have 8 legs? | spider | go to step 7 |
| 7 | Does it have 6 legs? | insect | go to step 8 |
| 8 | Does it have a shell? | snail | worm |
Key ideas
- Start at step 1, and answer every question in order.
- If the answer is yes, follow the yes column. If the answer is no, follow the no column.
- A key ends when you reach a name in the table.
- Do not skip a step, even if you think you know the name.
Method. Start at step 1 and follow the answer.
- Read step 1. Step 1 asks: Does it have a backbone? The robin answers yes.yes
- Find the next step. The yes column for step 1 says go to step 2.go to step 2
- Write the answer. 2
Check. Step 2 asks about feathers, and the robin has them. ✓
Method. Follow step 2.
- Read step 2. Step 2 asks: Does it have feathers? The robin answers yes.yes
- Read the name. The yes column for step 2 gives the name bird.bird
- Write the answer. bird
Check. Feathers and a beak make a bird. ✓
Method. Follow the steps one at a time.
- Step 1: backbone. Yes, so go to step 2.step 2
- Step 2: feathers. No, so go to step 3.step 3
- Step 3: fins and water. Yes, so the key gives the name fish.fish
- Write the answer. fish
Check. The goldfish is named after three steps. ✓
Watch out
Watch out: follow the answer for each question. A yes answer and a no answer lead to different steps, so do not use the same column twice.
Try it at home or school (with a grown-up). Look at the pictures of animals in a book with a grown-up. Use the animal key on one picture at a time. Say each step aloud, and write the name the key gives.
Exam tip
Grown-up tip. Ask: “Which question are you on? Did you answer yes or no? Where does the arrow go?” Let your child read each step, and say which number to go to next.
Exercise 3B Using a key for animals
Method. Read the table in section 3.2.
- Read step 1. The answer is yes, so the table says go to step 2.go to step 2
- Write the answer. 2
Check. Step 2 is about feathers. ✓
Method. Follow step 2.
- Read step 2. The answer is yes, so the name is given.yes
- Read the name. The name in the yes column of step 2 is bird.bird
- Write the answer. bird
Check. A robin is a bird. ✓
Method. Find the step that gives the name fish.
- Look at the table. The name fish is in the yes column of step 3.step 3
- Write the answer. 3
Check. A goldfish has fins and lives in water. ✓
Method. Follow the steps for a frog.
- Step 1. A frog has a backbone, so go to step 2.step 2
- Steps 2 to 5. A frog has no feathers, no fins, no fur, and no dry scaly skin.no
- Read the name. The no column of step 5 gives amphibian.amphibian
- Write the answer. amphibian
Check. A frog has moist skin. ✓
Method. Follow the steps for a lizard.
- Steps 1 to 4. A lizard has a backbone, no feathers, no fins and no fur.no fur
- Step 5. A lizard has dry scaly skin, so the yes column gives reptile.reptile
- Write the answer. reptile
Check. Lizards and snakes are reptiles. ✓
Method. Follow the steps for a dog.
- Step 1. A dog has a backbone, so go to step 2.step 2
- Step 4. A dog has fur, so the yes column gives mammal.mammal
- Write the answer. mammal
Check. Dogs feed their young on milk, so they are mammals. ✓
Method. Follow the steps for a spider.
- Step 1. A spider has no backbone, so go to step 6.step 6
- Step 6. A spider has 8 legs, so the yes column gives spider.spider
- Write the answer. spider
Check. Count the legs to check: a spider has 8. ✓
Method. Follow the steps for a ladybird.
- Step 1. A ladybird has no backbone, so go to step 6.step 6
- Step 6. A ladybird does not have 8 legs, so go to step 7.step 7
- Step 7. A ladybird has 6 legs, so the yes column gives insect.insect
- Write the answer. insect
Check. A ladybird is an insect with 6 legs. ✓
Method. Follow the steps for a snail.
- Steps 1 to 7. A snail has no backbone, no 8 legs and no 6 legs, so go to step 8.step 8
- Step 8. A snail has a shell, so the yes column gives snail.snail
- Write the answer. snail
Check. The shell is the feature that names the snail. ✓
Method. Follow the steps for a worm.
- Steps 1 to 7. A worm has no backbone, no legs, and so the key goes to step 8.step 8
- Step 8. A worm has no shell, so the no column gives worm.worm
- Write the answer. worm
Check. A worm has a long soft body and no legs. ✓
Method. Follow the key for a worm, then compare with Ruby’s prediction.
- Follow the key. A worm has no shell, so the key gives worm at step 8.worm
- Compare. The key gives worm, not snail, so Ruby’s prediction is wrong.not snail
- Write the answer. worm
Check. Testing a prediction with a key shows whether the prediction was right. ✓
Method. Follow the steps for a bat.
- Step 2. A bat does not have feathers, so go to step 3.step 3
- Step 4. A bat has fur, so the yes column gives mammal.mammal
- Write the answer. mammal
Check. Flying does not make a bat a bird. ✓
Method. Follow the key for a penguin.
- Step 1. A penguin has a backbone, so go to step 2.step 2
- Step 2. A penguin has feathers, so the key gives bird.bird
- Write the answer. yes. Accept any sentence that says a penguin has feathers, so the key gives the name bird.
Check. The key follows the features of the penguin. ✓