Thyroxin and iodine
Why salt packets say iodised.
Iodised salt
Many salt packets say iodised salt or enriched with iodine. Sunita's mother buys that kind.
Why do you think iodine is important in our food?
What this lesson covers
The idea
The thyroid gland makes thyroxin, which regulates carbohydrate, protein and fat metabolism to give the best balance for growth; iodine is essential for its synthesis, and iodine deficiency can cause goitre.
Iodised salt
Many salt packets say iodised salt or enriched with iodine. Sunita's mother buys that kind.
Why do you think iodine is important in our food?
- The thyroid gland needs it to make a hormone
- The stomach needs it to make sugar
- The heart needs it to beat faster
Iodine and the thyroid
Press Next step.
No iodine, no thyroxin
Iodine is essential for the synthesis of thyroxin. Without enough of it in the diet, the body is at risk of goitre.
The thyroid gland makes thyroxin, which regulates carbohydrate, protein and fat metabolism to give the best balance for growth. Iodine is essential for its synthesis, and iodine deficiency can cause goitre.
Notes
The thyroid gland makes thyroxin, which regulates carbohydrate, protein and fat metabolism for the best balance for growth. Iodine is essential for its synthesis, and iodine deficiency can cause goitre.
Check yourself
Which hormone does the thyroid gland make?
Which substance in the diet is essential for making thyroxin?
What can iodine deficiency in the diet lead to?
What does thyroxin regulate?
- Insulin. Insulin is produced by the pancreas.
- Adrenaline. Adrenaline is secreted by the adrenal glands.
- Thyroxin — correct. Yes!
- Iodine — correct. Yes!
- Carbohydrate. Thyroxin regulates carbohydrate metabolism. The substance essential for making it is iodine.
- Insulin. Insulin is a hormone made by the pancreas, not something the thyroid needs to make thyroxin.
- Dwarfism. Dwarfism is caused by a deficiency of growth hormone in childhood.
- Goitre — correct. Yes!
- A higher blood sugar level. Blood sugar rises when insulin is not secreted in proper amounts.
- The speed of nerve impulses along an axon. Thyroxin regulates metabolism of carbohydrates, proteins and fats.
- Blood pressure, salivation and vomiting. These involuntary actions are controlled by the medulla in the hind-brain.
- Carbohydrate, protein and fat metabolism, for the best balance for growth — correct. Yes!