Hormones — return questions key

1. CR1 · Return

Model answer. The jump within the first second is caused by nerve impulses, and the nerves still work, so the jump remains. The slower rise to a peak and the long, slow fall are caused by adrenaline. If adrenaline cannot act on the heart, that part is missing.

A full answer includes

• I chose "a jump in the first second, but no slower rise to a peak".
• I did not choose "no change at any time": the nerves to the heart still work.

Also accept

• a jump in the first second, but no slower rise to a peak

Watch for

• “No jump in the first second, but a slow rise to a peak after it.” — That trace has lost the nervous part and kept the hormonal part: the wrong way round. The nerves still work; adrenaline does not.
• “A jump in the first second, then a slow rise to a peak, as usual.” — The slow rise to a peak is caused by adrenaline acting on the heart, and the medicine stops that.
• “No change in the heart rate at any time after the fright.” — The nerves to the heart still work, so the fast jump in the first second still happens.

2. CR2 · Return

Model answer. Halfway back is (peak + resting rate) ÷ 2, so peak + 66 = 2 × 95 = 190, and the peak is 190 − 66 = 124 beats per minute. Check: (124 + 66) ÷ 2 = 95.

Checked automatically

• Peak heart rate (beats per minute): 124 (within ±0.5)
  • Common wrong answer 190 : That doubles 95 but forgets the resting rate. The peak plus 66 makes 190.
  • Common wrong answer 29 : That is the fall from halfway back to the resting rate. The peak is 95 + 29.
  • Common wrong answer 161 : That adds 95 and 66. The peak is 2 × 95 − 66.

A full answer includes

• I used halfway back = (peak + resting rate) ÷ 2, so peak = 2 × 95 − 66.
• I wrote 124 beats per minute.
• I did not simply double the halfway value.

Also accept

• 124 beats per minute

Watch for

• “190 beats per minute.” — That doubles the halfway value but forgets the resting rate: the peak plus 66 makes 190.
• “29 beats per minute.” — That is the fall from halfway back to the resting rate. Add it to 95 to reach the peak.
• “161 beats per minute.” — That adds 95 and 66. The peak is 2 × 95 − 66.

3. AR1 · Return

Model answer. First mistake: a hormone is a chemical substance, not an electrical signal; electrical impulses travel along neurones. Second mistake: a hormone does not act only next to its gland. It passes into the blood, which carries it round the body, and it alters the activity of specific target organs wherever they are: adrenaline from glands on the kidneys acts on the heart and the eyes. "Sent out by a gland" is right.

A full answer includes

• I wrote that a hormone is a chemical substance, not an electrical signal.
• I wrote that a hormone is carried by the blood round the body.
• I wrote that it alters specific target organs, which can be far from the gland.
• I did not write that a hormone is not made by a gland.

Also accept

• chemical, not electrical; carried by the blood to target organs anywhere, not only next to the gland

Watch for

• “A hormone is not made by a gland.” — That part of the student's sentence is right: hormones are produced by glands.
• “A hormone does act next to its gland, because it seeps out into the tissue around it.” — A hormone passes into the blood flowing through the gland, and the blood carries it to target organs all round the body.

4. AR2 · Return

Model answer. All three increases together are the effects of adrenaline, which is secreted in fight or flight situations such as sudden fear or stress. Being told to give a speech at once is such a situation. Dim light widens the pupils only; a meal and falling asleep do not raise all three.

A full answer includes

• I chose the speech.
• I did not choose the dark room: dim light explains the wider pupils only, not the faster breathing and heart rate.

Also accept

• being told to give a speech at once

Watch for

• “They have just walked from a bright room into a dark one.” — Dim light makes the pupils wider, but it does not raise the breathing rate and the heart rate. All three together point to adrenaline.
• “They have just finished eating a large meal.” — A meal does not make the breathing rate, heart rate and pupil diameter all rise at once.
• “They have just started to fall asleep in the chair.” — Falling asleep slows the breathing rate and the heart rate.

5. AR3 · Return

Model answer. A. Waiting nervously to go on stage is a fight or flight situation, so her adrenal glands secrete adrenaline. Adrenaline increases the heart rate and makes the liver release glucose into the blood, so the blood glucose concentration increases.

A full answer includes

• I chose row A.
• I did not choose row B: insulin lowers the blood glucose concentration.

Also accept

• A

Watch for

• “Row B: insulin, and the liver.” — Insulin lowers the blood glucose concentration, and it does not raise the heart rate. Both rises come from adrenaline.
• “Row C: adrenaline, and the pancreas.” — The hormone is right, but adrenaline acts on the liver, and the liver releases the glucose. The pancreas secretes insulin.
• “Row D: adrenaline, and the leg muscles.” — The muscles take glucose out of the blood and use it in respiration. The extra glucose comes from the liver.

6. GR1 · Return

Options as numbered on the pupil sheet: 1 — liver; 2 — pancreas; 3 — ovaries; 4 — adrenal glands; 5 — uterus; 6 — testes.

Model answer. Testosterone is secreted by the testes, oestrogen by the ovaries and adrenaline by the adrenal glands. (Supplement) Glucagon is secreted by the pancreas. The liver and the uterus are organs that hormones act on.

A full answer includes

• I matched testosterone to the testes.
• I matched oestrogen to the ovaries.
• I matched adrenaline to the adrenal glands.
• Supplement: I matched glucagon to the pancreas.
• I did not match glucagon to the liver.

Also accept

• testosterone testes; oestrogen ovaries; adrenaline adrenal glands; glucagon pancreas

Watch for

• “Oestrogen – uterus.” — Oestrogen acts on the uterus, but it is secreted by the ovaries beside it.
• “Glucagon – liver.” — The liver is a target of glucagon. Glucagon is secreted by the pancreas.
• “Testosterone – ovaries.” — The ovaries secrete oestrogen. Testosterone comes from the testes.

7. GR2 · Return

Options as numbered on the pupil sheet: 1 — kidney – adrenaline; 2 — adrenal gland – adrenaline; 3 — liver – none of the four; 4 — kidney – none of the four; 5 — liver – insulin; 6 — pancreas – insulin.

Model answer. Seen from the back, the person's right is on your right. J, the small gland on the upper tip of the organ beside the backbone on the person's right, is an adrenal gland: adrenaline. K, the matching organ beside the backbone on the person's left, is a kidney: it makes urine and secretes none of the four. L, the long, narrow gland lying across the body between the kidneys, is the pancreas: insulin. M, the broad organ high up on the person's right, is the liver: it is a target of insulin and secretes none of the four.

A full answer includes

• I matched J to adrenal gland – adrenaline.
• I matched K to kidney – none of the four.
• I matched L to pancreas – insulin.
• I matched M to liver – none of the four.
• I did not match the kidney to adrenaline: adrenaline comes from the small gland on it.

Also accept

• J adrenal gland – adrenaline; K kidney – none; L pancreas – insulin; M liver – none

Watch for

• “K is a kidney, which secretes adrenaline.” — The kidney makes urine. Adrenaline comes from the small gland on the tip of a kidney, like J.
• “M is the liver, which secretes insulin.” — The liver is a target of insulin. Insulin enters the blood in the long gland lying between the kidneys, L.
• “J is the kidney, which secretes none of the four.” — Look where the line ends: on the small gland on the tip of the kidney, not on the kidney itself.
• “L is the liver, which secretes none of the four.” — The liver is the broad organ high up on the person's right, M. L is long and narrow and lies between the kidneys.