Chapter 23 - done

Name four physiological functions of calcium.

1. signal molecule 2. part of intercellular cement that holds cells together at tight junction 3. cofactor in the coagulation cascade 4. affects the excitability of neurons

Which of the following transporters are known to transport thyroid hormones into target cells?

MCT8

The precursor chemical for ACTH synthesis is

POMC.

Excess secretion of growth hormone during adulthood will cause

acromegaly.

The endocrine gland that is a modified sympathetic ganglion is the

adrenal medulla.

Parathyroid hormone is

an amine hormone.

Transcellular transport of intestinal calcium is accomplished by entry into the epithelial enterocytes via

apical calcium channels

Thyroid hormones

are lipophilic and must bind to plasma proteins for transport to target cells.

A hormone that can lower blood levels of calcium ion is

calcitonin.

Elevated levels of calcium ion in the blood stimulate the secretion of the hormone

calcitonin.

Calcium reabsorption at the kidneys is promoted by the hormone

calcitriol.

The adrenal medulla produces

catecholamines.

What are the two distinct endocrine cell types that comprise the thyroid gland, and what do they secrete?

cells secrete calcitonin, and follicle cells secrete thyroid hormones.

The hypothalamic-pituitary-adrenal pathway begins with secretion of ________ into the ________ and transported to the ________.

corticotropin-releasing-hormone (CRH), hypothalamic-hypophyseal portal system, anterior pituitary

The most important metabolic effect of ________ is protection against ________, crucial to surviving significant stress.

cortisol, hypoglycemia

Damage to cells of the zona fasciculata of the adrenal cortex would result in

decreased ability to convert lipids to glucose.

Cortisol secretion peaks between ________ and ________.

early morning, noon

Premature closure of the epiphyseal plates could be caused by

elevated levels of sex hormones.

Excess growth hormone prior to puberty would result in

giantism.

Without cortisol's permissive effect on ________, an animal would die.

glucagon

:List four factors that affect normal body growth.

growth hormone and other hormones, adequate diet, absence of stress, genetics

Somatostatin is another name for

growth hormone-inhibiting hormone.

In bone, the calcium phosphate forms crystals of ________.

hydroxyapatite

The effects of thyroid hormone on peripheral tissue include

increased sensitivity to sympathetic stimulation.

Hyperthyroidism

increases protein catabolism.

The parathyroid glands produce a hormone that

increases the level of calcium ions in the blood.

GH stimulates the secretion of ________ from the liver and other tissue. This hormone has ________ feedback effect on growth hormone secretion.

insulin-like growth factor; negative

Thyroid hormone contains the mineral

iodine.

Vitamin D (calcitriol)

is formed by sunlight and bound to plasma protein for transport.

GH

is secreted by the anterior pituitary and binds to a plasma protein.

The C cells of the thyroid gland produce

only calcitonin.

Mature, less active bone cells are termed

osteocytes.

A condition that produces a reduction in bone mass or density sufficient to compromise normal function is

osteoporosis.

The thyroid gland is composed of many ________ that produce and store thyroid hormones.

thyroid follicles

Pendrin is an anion transporter important in the production of

thyroid hormone.

Thyroid hormones are structural derivatives of the amino acid ________.

tyrosine

________ is a result of deficient thyroid hormone secretion in infancy.

Cretinismx

Melanocortins includes one or more of the following:

ACTH and MSH

CRH stimulates the release of

ACTH.

The pituitary hormone that triggers the release of thyroid hormone from the thyroid gland is

TSH

ACTH is synthesized from a large glycoprotein called ________, which also produces ________ in the pituitary.

pro-opiomelanocortin (POMC), beta endorphin

Cholesterol is a precursor for the synthesis of

progesterone, aldosterone, and estradiol.

Increased blood calcium levels result in increased

secretion of calcitonin.

Iodine accumulation in thyroid cells involves symport with

sodium.

Crossover effects are sometimes seen among

steroid hormones.

Cortisol has the following effects:

suppresses the immune system and influences brain function.