chapter 18 The Endocrine System Flashcards
The three stages of the stress response or general adaptation syndrome, in order of occurrence, are the fast resistance response, the fight-or-flight response, and exhaustion.
True
False
False
The pituitary gland is the major integrating link between the nervous and endocrine systems, acts as an endocrine gland itself, and helps control the stress response.
True
False
False
Down-regulation makes a target cell less sensitive to a hormone while up-regulation makes a target cell more sensitive to a hormone.
True
False
True
If the effect of two or more hormones acting together is greater than the sum of each acting alone, then the two hormones are said to have a permissive effect.
True
False
False
In the direct gene activation method of hormone action, the hormone enters the target cell and binds to an intracellular receptor. The activated receptor-hormone complex then alters gene expression to produce the protein that causes the physiological responses that are characteristic of the hormone.
True
False
True
Which of the following comparisons are true?
1. Nerve impulses produce their effects quickly; hormonal responses generally are slower.
2. Nervous system effects are brief; endocrine system effects are longer lasting.
3. The nervous system controls homeostasis through mediator molecules called neurotransmitters; the endocrine system works through mediator molecules called hormones.
4. The nervous system can stimulate or inhibit the release of hormones; some hormones are released by neurons as neurotransmitters.
5. Neurotransmitters transmit impulses directly; hormones must bind to receptors on or in target cells in order to exert their effects.
1, 2, 3, 4, and 5
1, 2, 3, and 4
2, 3, 4, and 5
2, 4, and 5
1, 4, and 5
1, 2, 3 and 4
Insulin and thyroxine arrive at an organ at the same time. Thyroxine causes an effect on the organ but insulin does not. Why?
Thyroxine is a lipid-soluble hormone and insulin is not.
The target cells in the organ have up-regulated for thyroxine.
Thyroxine is a local hormone and insulin is a circulating hormone.
Thyroxine inhibits the action of insulin.
The organ’s cells have receptors for thyroxine but not for insulin.
The organ’s cells have receptors for thyroxine but not for insulin.
Which of the following is not a category of water-soluble hormones? Peptides Amines Eicosanoids Steroids Proteins
Steroids
Place in correct order the action of a water-soluble hormone on its target cell.
- Adenylate cyclase is activated, catalyzing the conversion of ATP to cAMP.
- Enzymes catalyze reactions that produce a physiological response attributed to the hormone.
- The hormone binds to a membrane receptor.
- Activated protein kinases phosphorylate cellular proteins.
- The hormone-receptor complex activates G proteins.
- Cyclic AMP activates protein kinases.
3, 5, 1, 6, 4, 2
3, 1, 5, 6, 4, 2
5, 1, 4, 2, 3, 6
3, 4, 5, 1, 6, 2
6, 3, 5, 1, 4, 2
3, 5, 1, 6, 4, 2
Hormones:
- Generally utilize negative feedback mechanisms to regulate their secretion.
- Will only affect target cells far removed from the hormone-producing secretory cells.
- Must bind to transport proteins in order to circulate in the blood.
- May be released in low concentrations but can produce large effects in the target cells because of amplification.
- Can regulate the responsiveness of the target tissue by controlling the number of receptor sites for the hormone.
1, 2, and 3
1, 2, 4, and 5
2, 3, and 4
2, 3, 4, and 5
1, 4, and 5
1, 4, and 5
The pituitary gland:
- Is located in the cribriform plate of the ethmoid bone.
- Is linked to the hypothalamus by the infundibulum.
- Has a posterior portion that contains axon terminals from hypothalamic neurosecretory cells.
- Produces releasing and inhibiting hormones.
- Has a vascular connection with the hypothalamus known as the hypophyseal portal system.
1, 2, and 4
2, 3, 4, and 5
2, 3, and 5
1, 2, 3, 4, and 5
2, 4, and 5
2, 3, and 5
The class of adrenal gland hormones that provides resistance to stress, produces anti-inflammatory effects, and promotes normal metabolism to ensure adequate quantities of ATP is:
Glucocorticoids Mineralocorticoids Androgens Catecholamines Gonadocorticoids
Glucocorticoids
The hormone that regulates the body's biological clock is: Melatonin Calcitonin Adrenaline Parathyroid hormone
Melatonin
Triiodothyronine and thyroxine promote T cell maturation.
True
False
False
FSH and LH:
Are secreted by the posterior pituitary gland and act on the gonads
Are secreted by the hypothalamus and act on the anterior pituitary gland
Are secreted by the anterior pituitary gland and act on the gonads
Are secreted by the gonads and act on the hypothalamus
Are secreted by the anterior pituitary gland and act on the gonads
