Which of the following is true?
1. Hormones regulate cellular functions, and generally negative feedback regulates hormone levels.
2. The circulating level of a hormone is held constant through a series of positive feedback loops.
3. Both lipid-soluble hormones and water soluble hormones bind to intracellular protein receptors.
4. The ducts of endocrine organs release their contents into the bloodstream.

The amino acid derivative among the following hormone is:-

1. Insulin
2. Epinephrine
3. Estradiol
4. Testosterone

Which of the following statement is correct in relation to the endocrine system?

1. Adenohypophysis is under direct neural regulation of the hypothalamus

2. Organs in the body like gastrointestinal tract. heart, kidney and liver do not produce any hormones

3. Non-nutrient chemicals produced by the body in trace amount that act as intercellular messenger are known as hormones

4. Releasing and inhibitory hormones are produced by the pituitary gland

How many of the following are peptide hormones?

Gastrin, Secretin, Cholecystokinin, Gastric inhibitory peptide, ANF, Erythropoietin

1. 3

2. 4

3. 5

4. 6

Which of the following is not true about hormones