SATs - Science Exercise 11 - Living Things Levels 5

Living Things - Levels 5 - 7 - Answers

Jane carried out some experiments with food. She wanted to find out if cream crackers contain as much energy as peanuts. She used the equipment shown below.

State two things Jane must do in her experiment to make it a fair test.

1. _same mass of nut and cracker; same _

2. _volume of water; same starting temperature_

Suggest a safety precaution that Jane should take.

__ wear goggles/ tie hair back; stand well back; etc __

The table shows information printed on a packet of peanuts and a packet of cream crackers.

Energy in kJ. Protein in g. Carbohydrate in g. Fat in g. Fibre in g.

100g. of cream crackers 2156 9.1 62.4 25.4 4.8

100g. of peanuts 2411 28.8 12.9 46.0 7.2

Jane burns 2g. of cream cracker under the beaker of water and then repeats the test with 2g. of peanut. Which test will give the greatest change in temperature of the water?

__________ peanut ____________

Use the information in the table to explain why peanuts are good emergency rations for a hiking expedition.

______ contains large amounts of energy/ large amounts of food value in small volume ______

Peanuts do not contain vitamin C. Underline the best source of vitamin C.

meat cheese oranges fish

Fibre does contain energy but our bodies cannot use it. Explain why.

_____ We are unable to digest/ breakdown fibre _____

Why is fibre an essential part of our diet?

__ prevents constipation; provides bulk; keeps food moving through your gut; keeps your gut healthy _

Air is a mixture of gases. It contains nitrogen, oxygen, water vapour, noble gases and carbon dioxide. The air we breathe in (inhaled air) and the air we breathe out (exhaled air) are different. List three differences in the composition of inhaled and exhaled air.

Compared to inhaled air, exhaled air contains:

a) _____ more carbon dioxide _______

b) _____ less oxygen ______________

c) ____ more water vapour/ moisture __

Name the tube that connect the mouth to the lungs

______ trachea/ wind pipe _____

The walls of this tube are stiffened with 'rings' of cartilage. Why is this so?

to keep the tube open/ to prevent the tube from flattening

This is part of the complex food web in a forest.

Basing your answers on this information only:

Name one top carnivore and one herbivore.

top carnivore: hawk, fox, buzzard

herbivore: caterpillar/ aphid

The squirrels were damaging buds on the trees and the forest manager decided to shoot them. Giving reasons for your answers say how this might affect:

(i) the number of foxes?

might reduce because less food is available

(ii) the number of mice?

might reduce because more of them are eaten by the foxes

In a year, a sparrow hawk may eat 150 small birds. This is a mass of well over 2kg of meat, yet a sparrow hawk only weights about 0.5kg. Explain why most of the energy from the bodies of the small birds does not remain in the sparrow hawk?

energy is lost as heat or by respiration or to fly/ move etc.; Some food is wasted/ not digested/ excreted.

Last modified on: Tuesday, June 9, 1998.