Identify the statement that correctly describes the catecholamine, Dopamine:

1. It cannot act as a hormone
2. It is a neuropeptide
3. Its structure has a sterol nucleus
4. It may act as a neurotransmitter or a hormone

Identify the incorrect statement regarding the main glucocorticoid cortisol in the human body:
1. Cortisol is important during fetal development for the proper differentiation of many tissues
2. Cortisol levels increase during stress and act to increase the plasma concentrations of glucose, amino acids, and fatty acids
3. Cortisol is a potent anti-inflammatory agent and is useful for treating diseases such as arthritis
4. Cortisol promotes the action of the immune system

Hypercortisolism or Cushing's syndrome:
1. is caused by increased secretion of cortisol
2. is a disorder of the adrenal medulla
3. may be caused by hyposecretion of ACTH
4. is characterized by major changes in protein distribution in the body

The correct statement regarding the human Growth hormone would be that it:
1. Promotes postnatal elongation of bones, primarily during adolescence
2. Is released from posterior pituitary gland
3. Cannot act directly on target tissues, but only by first stimulating IGF-1 release from the liver
4. Is the only hormone that affects growth

The major portion of the posterior lobe of the pituitary gland is called as:

Thyroxine and triiodothyronine:
1. are synthesized by stratified cuboidal epithelial cells called follicular cells
2. are very soluble in water and therefore easily soluble in the bloodstream
3. are synthesized and secreted by parafollicular cells
4. are ultimately formed from the amino acid, L-tyrosine

All the following regarding parathyroid glands are true except:

The beta cells of the endocrine pancreas secrete insulin that:
1. is secreted by the alpha cells of the pancreas
2. promotes the entry of glucose and amino acids into tissue cells
3. promotes the breakdown of glycogen (glycogenolysis) and fat (lipolysis)
4. falls in level immediately after a meal is eaten

Melatonin is the hormone that regulates wakefulness. Which of the following does not correctly characterize melatonin?
1. It is secreted by the pineal gland, the gland located in the roof of the third ventricle.
2. Its secretion is highest in children aged one to five and decreases thereafter.
3. It may have an important role in the onset of puberty.
4. More is secreted in the daytime than at night.

The human placenta has endocrine functions that does not secrete:
1. prolactin
2. estrogens
3. progesterones
4. human chorionic gonadotropin (HCG)