HELP

1 The table below shows some information about Charlotte′s body before and after she went on a six month fitness training programme.

Factor / Before training / After training
Heart rate in beats per minute / 90 / 72
Breathing rate in breaths per minute / 18 / 16
Body weight in kg / 70 / 65
Diameter of leg around the calf muscle in cm / 36 / 41

a How has training affected Charlotte′s:

i heart rate? ii body weight? iii calf muscle?

b i What has happened to the strength of Charlotte′s heart after six months of training?

ii Explain why this happened.

c Explain why Charlotte′s calf diameter has increased.

d When she began her training, Charlotte did not warm up properly. She often damaged the tendons in her ankle.

i What is the job of a tendon?

ii Why did Charlotte′s tendons become damaged?

CORE

The diagram shows the muscles in Lester′s leg, seen from the outside of his leg.

2 a Which muscle will contract when Lester raises his leg to the front?

b Which muscle will contract when Lester stands on tiptoe?

c Describe what is meant by ′muscles work in pairs′ by explaining how muscles E and G work together.

d Which lettered part is a tendon?


e i Describe how Lester′s leg will move when muscle A contracts.

ii What type of joint is moved by muscle A?

f i Lester over-stretches and strains muscle B. What happens to this muscle when it becomes strained?

ii Why must Lester now stop doing more exercise?

EXTENSION

3 Clare is a rock climber. She has very strong arms. Sometimes, when she has been climbing a very steep cliff, her arm muscles become very tired and her fingers cannot grip so well. This is because lactic acid, from anaerobic respiration, builds up in Clare′s muscles when they work hard. Lactic acid is moved away from Clare′s muscles by her blood. If she has a good rest, the lactic acid clears from her arm muscles and she can grip tightly again.

a Clare′s arm muscles are bigger than those in her friend′s arm, who is not a rock climber. Explain why Clare′s muscles are bigger.

b i Extra capillaries have grown in Clare′s arms, as she has done more and more rock climbing. Why has this happened?

ii When Clare first began climbing her arms became tired very quickly. Now she can hang on for much longer before they tire. Explain why this has happened.

c Clare loves to have a cooked breakfast to give her plenty of energy before she goes climbing. She likes plenty of bacon, fried sausages, fried bread, fried eggs and lots of buttered toast. What advice would you give to Clare about her diet and why would you give her this advice?

d In the winter, when Clare cannot get outdoors to climb, what should she do to keep her arms fit for the next summer?

© Harcourt Education Ltd 2004 Catalyst 3

This worksheet may have been altered from the original on the CD-ROM.