anatomy and physiology CH 11

list the steps in the action of most nonsteroid hormones

1: a hormone binds to its receptor. 2: the resulting hormone-receptor complex activates a membrane protein called a G protein. 3: the G protein activates an enzyme called adenylate cyclase, which is a membrane protein. 4: in the cytoplasm, activated adenylate cyclase catalyzes the formation of cAMP from ATP. 5: cAMP activates another set of enzymes, called protein kinases, which transfer phosphate groups from ATP to their substrate molecules, which are specific proteins in the cell. This action, called phosphorylation, alters the shapes of these substrate molecules, thereby activating them.

functions of hormones include which of the following? A: control rates of certain chemical reactions. B: transport substances across cell membranes. C: help regulate water and electrolyte balances. D: all of the above

C

releasing hormones come from which one of the following. A: thyroid gland. B: anterior pituitary gland. C: posterior pituitary gland. D: hypothalamus

D

List the steps of steroid hormone action

1: lipid-soluble steroid hormone diffuses through the cell membrane. 2: the steroid hormone binds a specific protein molecule-the receptor for that hormone. 3: the resulting hormone-receptor complex binds in the nucleus to specific sequences of the target cell's DNA, activating transcription of specific genes into messenger RNA (mRNA) molecules. 4: the mRNA molecules leave the nucleus and enter the cytoplasm. 5: translation of mRNA molecules leads to the synthesis of specific proteins.

list the hormones secreted by the pancreatic islets, the type of cell that secretes each, and the actions of these hormones.

Glucagon is released by alpha cells in response to low blood glucose concentration. This causes the liver to break down glycogen and convert it into glucose thereby increasing blood glucose concentration. Insulin does the complete opposite and seeks to lower blood glucose concentration in response to high blood glucose. It is released by beta cells.

diagram the control of thyroid hormone secretion

figure 11.9 pg 310

under which of the following conditions would you expect an increase in antidiuretic hormone secretion?

an individual is rescued after three days in the desert without food or water

define stress

any factors that change the body's internal environment

list the similarities and differences between the short-term alarm stage of stress and the long-term resistance stage.

both stages prepare the body for a fight, but over time the constant release of cortisol from long-term resistance can cause your body to be susceptible to infectious diseases and cancer by lowering the number of white blood cells. Persistent levels of cortisol may also increase the risk of developing high blood pressure, atherosclerosis, and gastrointestinal ulcers.

match the adrenal hormones with their source and actions

cortisol: adrenal cortex; fatty acid release. Aldosterone: adrenal cortex; sodium retention. Epinephrine; adrenal medulla; fight-or-flight response

contrast endocrine glands and exocrine glands

exocrine glands secrete their products mostly through ducts onto large surfaces of the body. Endocrine glands secrete hormones into the tissue fluid or blood.

draw a diagram that shows how the secretion of parathyroid hormone is regulated

figure 11.12 pg 314

draw a diagram illustrating the regulation of cortisol secrection

figure 11.14 pg 317

draw a diagram that shows how the secretion of pancreatic hormones is regulated

figure 11.17 pg 318

draw diagrams of the three mechanisms by which hormone secretion is controlled, including negative feedback

figure 11.5 pg 306

describe the control of growth hormone secretion

from the hypothalamus comes two types of hormones: one is growth hormone-secretion hormone which activates GH, and growth hormone-inhibiting hormone (also called somatostatin) inhibits growth hormone secretion. Nutritional states also influence control of GH. GH is released in response to low blood glucose concentration, and when blood glucose is high GH decreases.

list the hormones secreted by the anterior pituitary gland

growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), and adrenocorticotropic hormone (ACTH). Follicle-stimulating hormone (FSH), and luteinizing hormone (LH).

match the following hormones with their actions. More than one hormone can correspond to the same function

growth hormone: cell division. prolactin: milk production. Adrenocorticotropic hormone: controls secretion of adrenal cortex hormones. Follicle-stimulating hormone: exerts action on gonads. Luteinizing hormone: exerts action of gonads. Thyroid-stimulating hormone: metabolic rate

define hormone and target cell

hormones flow throughout the body and regulate metabolic activities such as water, electrolyte balance, growth, and much of the physiology of the body. Target cells have specific receptors for the hormone

describe the location and structure of the thyroid gland

it consists of two large lobes which are connected by a broad isthmus. It is inferior to the larynx and anterior and lateral to the trachea. It is made up of several secretory parts called follicles. These follicles are filled with a substance called colloid.

describe the location and general function of the pineal gland

it is a small structure located between the cerebral hemispheres, where it is attached to the upper part of the thalamus near the roof of the third ventricle. It secretes melatonin in response to changing light conditions outside the body. Melatonin helps regulate circadian rhythms (daily sleep-wake cycles)

describe the location and structure of the pancreas

it is elongated, somewhat flattened, and posterior to the stomach and partly posterior to the parietal peritoneum. A duct joins the pancreas to the duodenum.

describe the location and structure of the pituitary gland

it is located at the base of the brain, where the pituitary stalk attaches it to the hypothalamus. The gland is about 1 centimeter in diameter and consists of an anterior lobe and posterior lobe

describe the location and structure of the parathyroid glands

it is located on the posterior surface of the thyroid gland. Most individuals have 4 lobs of the parathyroid gland.

explain the general function of parathyroid hormone

it secretes parathyroid hormone which increases the blood calcium ion concentration and decreases the blood phosphate ion concentration.

compare and contrast chemical communication in the nervous and endocrine systems

nervous system cells are neurons, endocrine system cells are epithelial and others. Nervous system chemical signals are neurotransmitters, endocrine system chemical signals are hormones. Specificity of response in nervous system is receptors on postsynaptic cell, for endocrine system it is target cells. Speed of onset in nervous system is seconds, and in endocrine system it is seconds to hours. Duration of action in nervous system is very brief unless neuronal activity continues, and in endocrine system it may be brief or may last days even if secretion ceases.

explain the specificity of a hormone for its target cell

only target cells respond to hormones because they have specific receptors that hormones can bind too.

explain how prostaglandins are similar to hormones and how they are different

prostaglandins regulate how local tissues function, and only in the organ they originate from. Hormones can be produced from the adrenal gland and affect many different organ tissues, so hormones are much more broad. Prostaglandins are also generally in small quantities, but are very potent

prolactin does which of the following?

stimulates breast milk production

name 5 additional hormone-secreting organs

testes, ovaries, placenta, heart, and kidneys

distinguish between the adrenal medulla and the adrenal cortex

the adrenal gland consists of two parts; the inner part is the adrenal medulla and the outer part is the adrenal cortex. They aren't divided distinctly, but they have different functions by secreting different hormones.

describe the anatomical differences between the anterior and posterior lobes of the pituitary gland

the anterior pituitary is enclosed by connective tissue which are largely epithelial tissue and are organized by blocks which surround many thin-walled blood vessels. The posterior pituitary consists mostly of axons and neuroglia, unlike the anterior pituitary, which is composed primarily of glandular epithelial cells. These neuroglia originate from the neurons in the hypothalamus.

explain the two ways in which the brain controls pituitary gland activity

the hypothalamus has axons that extend down into the posterior pituitary gland (posterior lobe) and cause it to release posterior pituitary hormones. The hypothalamus also secretes hormones that the blood carries directly to target cells in the anterior pituitary gland.

describe the functions of the posterior pituitary gland

the posterior pituitary gland is responsible for releasing antidiuretic hormone and oxytocin. Diuretic hormones determine the amount of fluid the kidneys need to secrete urine, so antidiuretic reduces the amount of fluid the kidneys use. If it is damaged you can end up with diabetes insipidus which is where a patient can end up producing up to 15 liters of very dilute urine per day. Oxytocin is needed for women to have smooth muscle contractions in the uterus. It also helps stimulate specialized cells involved in milk-production glands.

describe the location and general function of the thymus

the thymus lies in the mediastinum, posterior to the sternum and between the lungs. It is relatively large in children and shrinks as we age. It secretes hormones called thymosins that affect the production and differentiation of certain white blood cells (lymphocytes).

match the hormones from the thyroid gland with their descriptions

thyroxine: has 4 iodine atoms. triiodothyronine: most potent at controlling metabolism. Calcitonin: regulates blood calcium

list the source of control for each thyroid hormone

thyroxine: thyroid-stimulating hormone from the anterior pituitary gland. Triiodothyronine: thyroid-stimulating hormone from the anterior pituitary gland. Calcitonin: blood calcium concentration