Keeping internal conditions constant
1
a
The human body must keep internal conditions constant.
List A shows some conditions.
List B shows some monitoring or control centres.
Match each condition with its correct monitoring or control centre.
List A
(3)
List B
blood glucose level
kidneys
body temperature
pancreas
blood water content
thermoregulatory centre
skin
b
Choose the correct words from the list below to complete the sentence. (2)
amino
fatty
kidney
lactic
liver
lung
pancreas
Urea is produced in the ……………… by the breakdown of ……………acids.
2
a
Which two of the following substances are found in the urine of a healthy
person? Circle your answers.
glucose
mineral
ions
proteins
water
AQA B3.3 Controlling internal conditions – Joe Ewen, Rebecca Timms and Rebecca Bartlett
(Cheney School)
b
A person with kidney disease can be treated by dialysis.
The diagram shows how dialysis works. The circles represent molecules of
different substances.
Choose the correct word or phrase to complete each sentence.
i
During dialysis, urea moves out of the ……………… .
blood cells
ii
blood plasma
dialysis fluid
During dialysis, urea moves into the ……………… .
blood cells
blood plasma
digestion
(1)
dialysis fluid
iii Urea moves by the process of ……………… .
diffusion
(1)
(1)
transpiration
AQA B3.3 Controlling internal conditions – Joe Ewen, Rebecca Timms and Rebecca Bartlett
(Cheney School)
iv To allow the movement of urea, the dialysis
membrane is ……………. .
impermeable
v
(1)
partially permeable
thick
The urea can pass through the membrane because the
urea molecules are ………………. .
large
c
round
(1)
small
For most patients, a kidney transplant is better than continued dialysis
treatment.
Underline the correct phrase to complete the sentence.
One major problem with a kidney transplant is that …
(1)

… drug treatment is needed to suppress the immune system.

… hospital visits are needed three times a week.

… yearly costs are higher than for dialysis.
AQA, 2002
3
When a person has a kidney transplant, the donor kidney must be matched to their
tissue type.
Choose the correct words from the list below to complete the sentences.
antibodies
antiseptics
protein
aspirin
immunosuppressants
urea
On the surface of the kidney cells are antigens …………………….
Antigens are made of …………………….
The antigens may be attacked by the person’s …………………….
AQA B3.3 Controlling internal conditions – Joe Ewen, Rebecca Timms and Rebecca Bartlett
(Cheney School)
To prevent the attack on the donor kidney the person is
given drugs called …………………….
4
(3)
When a person gets too cold, the organs cannot function properly. Below 35 °C the
person could die. Alcohol causes blood vessels to stay dilated.
A person found collapsed on a cold mountain should not be given an alcoholic
drink. Explain why.
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5
In this question you will be assessed on using good English, organising information
clearly and using specialist terms where appropriate.
A person with type 1 diabetes cannot produce enough of the hormone insulin.
Some diabetics use an insulin pump that is attached to the body. They can increase
or decrease the amount of insulin which is injected, depending on
their lifestyle.
Describe how insulin controls blood glucose levels and explain why a diabetic may
need to change their insulin levels at certain times.
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AQA B3.3 Controlling internal conditions – Joe Ewen, Rebecca Timms and Rebecca Bartlett
(Cheney School)
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AQA B3.3 Controlling internal conditions – Joe Ewen, Rebecca Timms and Rebecca Bartlett
(Cheney School)