Pupil sheet · Excretion and the kidneys

Excretion and the kidneys — final check

Name ______________________ Date ____________

Work alone, with the lesson closed. Answer every question; there are no hints.

1. identify

The picture shows the urinary system from the front. A nurse passes a thin, soft tube into the body from the outside to drain the urine that is being stored. Which row is correct?

A painted picture of the urinary system seen from the front, with four parts lettered: M, a bean-shaped organ high in the back of the abdomen, on the person's left; N, a thin tube running down from M; V, a rounded bag low in the body that N leads into; W, a tube leading down out of V to the outside.

Row	Tube that the nurse's tube passes along	Organ that stores the urine	Tube for urine that a person has two of
A	W	V	N
B	N	V	W
C	W	M	N
D	N	M	W

Circle one answer.

2. identify

On Monday a pupil sits at a desk all day. On Tuesday the pupil eats the same meals with much more salt added, drinks the same volume of water, and spends two hours cycling. The day is cool, so the pupil hardly sweats. Which row shows how Tuesday compares with Monday?

Row	Mass of ions in the urine	Volume of carbon dioxide breathed out	Organ that excretes the extra ions
A	more	more	kidneys
B	more	the same	kidneys
C	the same	more	kidneys
D	more	more	lungs

Circle one answer.

3. identify

Supplement. The picture shows two teaching models on stands. Look at the kidney model on the left, which is cut lengthways. Its maker painted a row of small dark dots on the cut face, and some fan shapes. Which row is correct?

A painted picture of two models on white stands. On the left, a model kidney cut lengthways stands upright, with a cut slice lying in front of it. It has a reddish band with a row of dark dots just under its surface, striped fan-shaped areas inside that band, a cream branching space in the middle, a red and a blue vessel at its inner dent and a cream tube pointing down. On the right, a model of one nephron: a cup round a knot of red capillaries, a coiled yellow tube with a long loop, and a wide tube with side branches.

Row	Region with the row of dark dots	Region with the fan shapes	Cream tube leaving the bottom of the kidney
A	cortex	medulla	ureter
B	medulla	cortex	ureter
C	cortex	medulla	urethra
D	medulla	space where urine collects	ureter

Circle one answer.

4. identify

Supplement. Blood flows into a glomerulus in one small vessel and out of it in another. Compare the blood flowing out with the blood flowing in, over one minute. Which row is correct?

Row	Volume of plasma	Mass of protein	Mass of glucose
A	less	the same	less
B	less	less	less
C	the same	the same	less
D	less	the same	the same

Circle one answer.

5. identify

Supplement. A computer model of a nephron is run with four settings. Each time, 300 water particles, 30 glucose particles and 60 ion particles are filtered into the capsule. The table shows how many of each are left in the urine at the end of the tubule. Which setting reabsorbs as a healthy nephron does?

Row	Water particles left in the urine	Glucose particles left in the urine	Ion particles left in the urine
A	3	0	30
B	3	0	0
C	3	12	30
D	150	0	30

Circle one answer.

6. explain

Supplement. The table shows the concentrations of ions and of urea in one person's filtrate and urine. From filtrate to urine, the urea becomes about 60 times as concentrated, but the ions less than 2 times. Explain why the two change by such different amounts.

Substance	Filtrate (g per dm³)	Urine (g per dm³)
ions	7.2	13
urea	0.28	17

7. explain

Supplement. A growing 12-year-old and an adult eat the same mass of protein each day. The child excretes less urea. Explain why, using assimilation.

8. identify

Supplement. A man's liver is badly damaged, and its cells can no longer deaminate amino acids. He eats the same meals as before, and his kidneys still work normally. Which row shows how his blood and urine compare with before the damage?

Row	Amino acids in the blood	Urea in the blood	Urea in the urine
A	higher	lower	less
B	higher	higher	less
C	higher	the same	the same
D	the same	lower	less

Circle one answer.

9. describe / explain

Supplement. Stones block both of a man's ureters, and he is not yet treated. The table shows the concentration of urea in his blood over five days. (a) Describe the change. (b) Explain why the concentration changes in this way. (c) Explain why this is dangerous.

Day	Urea in the blood (g per dm³)
1	0.26
2	0.48
3	0.70
4	0.91
5	1.13

(a) Change

(b) Why