Exam III - Endocrine

Which one of the following is caused by the secretion of atrial natriuretic hormone by the heart?

Decrease in blood pressure

During times of stress, which one of the following glands releases CRH to stimulate the anterior pituitary to release ACTH?

Hypothalamus

Luteinizing hormone is considered a gonadotropin because of which one of the following reasons?

It promotes the growth of reproductive organs in both males and females.

Which one of the following hormones stimulates the production of testosterone in males?

LH

Hormones act upon specific target tissues because?

Target tissues display the appropriate receptor for a particular hormone

Insulin helps regulate blood sugar at homeostatic levels by?

Promoting the entry of glucose into cells

The number of cases of Type 2 diabetes is increasing mainly due to an increase in three major risk factors: obesity, insufficient exercise, and unhealthy diets.

True

The following is a list of events involved in the activation of a cell by a steroid hormone. Which one of the following answers best represents the order in which the steps occur?

4. diffusion of the hormone through a target cell membrane 3. formation of a hormone-receptor complex 2. activation of a gene 5. production of a protein 1. cellular response to the hormone

A goiter results from low dietary iodine levels?

Because thyroxine cannot be made, which results in high levels of TSH

The secretion of oxytocin during childbirth stimulates ADH release by the anterior pituitary gland.

False

FSH is a hormone important to the proper functioning of the ovaries and testes. This hormone will not be released from the anterior pituitary until ________ is released from the hypothalamus.

GnRH

All of the following statements about the endocrine system are TRUE EXCEPT which one?

Hormones act more quickly than the nervous system.

Uptake of blood glucose by liver cells is stimulated by ?

Insulin

Which two endocrine glands exert the most control over blood calcium levels?

Thyroid and parathyroid

The action of nonsteroid hormones often results in conversion of ATP to cyclic AMP, which then functions?

To initiate a cascade of enzyme activation's

When oxytocin is released during childbirth, the hormone targets cells in the?

Uterus

Calcitonin and PTH have opposing effects on blood calcium levels.

True

Steroid hormones bind to receptors in the nucleus to activate or deactivate genes.

True

Steroid hormones typically move across the cell and nuclear membranes to bind to receptors in the nucleus.

True

Hyposecretion of ADH results in?

Diabetes insipidus

An individual, driving through his neighborhood, suddenly jams on his car brakes to avoid hitting a child who runs into the road after a ball. A few seconds later, the driver finds that he is shaking, and his heart is pounding. This is primarily due to the secretion of which one of the following?

Epinephrine from the adrenal medulla

Epinephrine and norepinephrine secreted by the adrenal gland enhance the response of the parasympathetic nervous system.

False

The alpha, beta, and delta cells located in the islets of Langerhans of the thyroid produce three different hormones that are important in the regulation of sodium and potassium levels of the blood.

False

The responsiveness of cells to calcitonin increases as an individual ages; maximum responsiveness occurs in elderly individuals as a mechanism to improve the stability and strength of bones.

False

The thymus produces two peptides that function to?

Aid in the maturation of T lymphocytes

The ovaries of women function as endocrine organs by producing?

Estrogen and progesterone

In females, LH promotes the monthly development of the egg and FSH causes release of the egg from the ovary.

False

In order for all hormones to cause a response, they must first bind to an appropriate receptor on the target cell's membrane.

False

Insulin helps regulate blood sugar levels by stimulating the release of glucose from glycogen stores.

False

Thyroxine is released from the thyroid gland in response to the presence of?

TSH

Which one of the following hormone pairs is antagonistic, in that they have opposing effects?

Glucagon & insulin

Which one of the following is required in the diet in order for active thyroid hormones to be produced?

Iodine

Which one of the following causes the release of epinephrine and norepinephrine from the adrenal medulla?

Sympathetic nerves

The endocrine system has certain characteristics that set it apart from the nervous system. Which one of the following characteristics is typical of the endocrine system, but NOT the nervous system?

The agents of communication are always in the form of a chemical.

During prolonged fasting, cortisol assists in maintaining blood glucose levels by stimulating the conversion of proteins to amino acids in muscle.

True

Nitric oxide helps regulate blood flow in many tissues and is involved in the development and control of penile erection.

True

Somatostatin functions to inhibit both insulin and glucagon.

True

Cortisol is a glucocorticoid that helps maintain blood glucose levels during fasting by?

Promoting the conversion of amino acids into proteins in muscle tissues