Exam practice
Every question from the end of every unit, with hints and answers to open. After you check an answer, mark how you did, and come back to the ones you didn’t get.
12 questions
Unit 5 · Life Process
2. Fill in the blanks
Living things take in ______ and give out ______ in respiration.
Answer
Living things take in oxygen and give out carbon dioxide in respiration.
Animals like fish and frogs reproduce by laying ______ in water.
Answer
Animals like fish and frogs reproduce by laying eggs in water.
Giving off extra water from a plant’s leaves is called ______.
Answer
Giving off extra water from a plant’s leaves is called transpiration.
In photosynthesis, plants take in ______ and give out ______.
Answer
In photosynthesis, plants take in carbon dioxide and give out oxygen.
In an animal’s body, things are usually carried around by the ______.
Answer
In an animal’s body, things are usually carried around by the blood.
4. Answer these questions
What is a life process?
Answer
A life process is a job that a living thing does again and again, all its life, to stay alive. Nutrition, respiration, transportation, excretion and reproduction are life processes.
What are the life processes of living things?
Answer
- Nutrition: getting food.
- Respiration: getting energy from food, with oxygen.
- Transportation: carrying food, water, oxygen and wastes around the body.
- Excretion: getting rid of wastes.
- Reproduction: making young ones.
What does a plant excrete?
Answer
- Carbon dioxide, from respiration.
- Oxygen, from making food.
- Extra water, as water vapor from the leaves (transpiration).
- Resin and latex, from the stem.
Can all plants make their own food? Give a reason.
Answer
No. Only green plants can make their own food, because only they have chlorophyll. Chlorophyll catches the sunlight needed to make food. A plant with almost no chlorophyll, like dodder (akashbeli), the yellow, leafless vine that climbs over bushes, can’t make its own food. It takes its food from the plant it grows on. (Mushrooms can’t make food either, but they are not plants.)
Write any two differences between autotrophs and heterotrophs.
Answer
- Autotrophs make their own food. Heterotrophs can’t; they take food from others.
- Autotrophs have green chlorophyll. Heterotrophs have none.
- Autotrophs: green plants, like mango and grass. Heterotrophs: animals and mushrooms.
Breathing and respiration are different. Do you agree? Explain.
Answer
Yes, they are different.
- Breathing is taking oxygen into the body and giving carbon dioxide out. It happens in the breathing organs, like the lungs.
- Respiration is breaking down food with oxygen, inside the body, to get energy. It makes carbon dioxide and water. It happens in every part of the body.
Breathing brings in the oxygen that respiration uses, and takes away the carbon dioxide it makes.
When we have a headache or a stomach ache, we swallow a medicine. Which life process carries the medicine from the stomach to the part that hurts? Explain.
Answer
Transportation. The medicine dissolves in the stomach and passes into the blood. The heart pumps the blood all round the body. So the medicine reaches every part, including the part that hurts, such as the head.