Endocrine System _ Mam Phys ii

Which of these is release by glands or specialized cells into the bloodstream and influences cells at another location?

Endocrine hormone

which type of hormone do the ovaries and testes primarily secrete?

steroids

which class of hormone is made from cholesterol

steriods

most hormones belong to which class?

peptides

The half life of adrenal hormones is longer than the half-life of steriod hormones which are bound to receptors.

false

hormones levels in the bloodstream are usually controlled by negative feedback loops.

true

Down-regulation of a hormone can occur as a result of?

• inactivation of some of the receptor molecules

• inactivation of some of the intracellular protein signaling molecules

• temporary sequestration of the receptor inside the cell

• destruction of receptors by lysosomes after internalization

• decrease production of receptors

The hypothalamus communicates with the anterior pituiatry with hormone and the posterior pituitary through nervous signals.

true

Which gland secretes GnRH?

hypothalamus

What is the target tissue of LH?

gonads

Growth hormones is the only anterior pituitary hormone that affects most tissues directly rather than manipulating a target gland.

true

Acromegaly can be a result of a tumor in GH producing cells

true

Which of these is a posterior pituitary hormone?

• ADH

• oxytocin

T3 and T4 are carried in the blood bound to plasma proteins.

True

Which of these is true about the adrenal gland?

• the paired glands sit just anterior to the kidneys

• the adrenal medulla comprises the central 20% of the gland

• the adrenal cortex can secrete 30 types of corticosteroids

90-95% of cortisol is carried in the blood on a transporter protein.

true

Which zone of the adrenal cortex is in the middle?

zona fasciculata

Increases in blood glucose levels causes a 2 stage increase in insulin secretion

true

Which type of cells secrete glucagon?

alpha

Insulin promotes protein synthesis and storage

true

Which of these affect the same cells that produced them?

autocrines

Which type of hormone is sometimes derived from a semi-essential amino acid?

amine

Hormones always work very quickly from the moment of the release

false

Which type of hormone is sometimes derived from a semi-essential amino acid?

amine

hormones always work very quickly from the moment of release.

false

Which type of hormone is cleared from the body more slowly?

hormones bound to plasma proteins

How are hormones cleared from the plasma?

all of the above

How does negative feedback work to control hormone secretion?

• it can occur at the gland

• it can occur at the target tissue

• it can affect storage

• it can affect release

• it can affect the number of receptors available

which hormonal event is under positive feedback control?

release of oxytocin during labor

where are hormone receptors found in or on a cell?

• as an integral membrane protein

• cytoplasm

• nucleus

We can control the number of hormone receptors available to bond to hormone by both up regulation and down regulation.

true

Epinephrine can bind with receptors on neurons to open ion channels and move the cell towards threshold

true

Which of these can happen after a hormone binds to a receptor?

• ion channel linked receptors can change the permeability of a cell membrane by opening opening or closing ion channels

• activation of intracellular enzymes

• activation of genes

steroid hormones diffuse across cell membranes and bind with cytoplasmic receptors.

ture

which of these are hypothalamic hormones?

• growth hormone releasing hormone

• gonadotropin releasing horomone

• thyrotropin releasing hormone

the primary effect of growth hormone is to cause growth in tissues by causing an increase in cells size and an increase in the rate of mitosis

true

what are the metabolic effects of GH

• increase in protein synthesis

• increase fat utilization

• decrease carbohydrate utilization

GH levels decrease as a person ages

true

Which GH abnormality results from a generalized deficiency of AP hormone during childhood that causes all parts of the body to develop in the correct proportion but at a reduced rate?

pituitary dwarfism

in which process/processes does oxytocin have a role?

• labor

• milk ejection

• copulation

oxytocin triggers milk let-down while prolactin triggers milk production

true

a complete lack of secretion of thyroxine and triiodothyronine from the thyroid gland results in what percentage reduction of basal metabolic rate?

40-50

Because humans cannot make iodine to use in the production of thyroxine and triiodothyronine, we must acquire it in our diet

true

Triiodothyronine shows effects in the body fast than thyroxine

true

triiodothyronine and thyroxine cause a/an ____________ in fat utilization.

increase

which of these are physiological characteristics of hypothyroidism?

• fatigue

• decreased cardiac output

• increased mass

in which of these do glucocorticoids have an effect?

• carbohydrate metabolism

• fat metabolism

Which of these can cause an increase in ACTH release which is followed by an increase in cortisol release?

• infection

• trauma

• intense heat or cold

cortisol can block inflammation by stabilizing lysosomal membranes to prevent release of proteolytic enzymes.

true

Which of these can cause an increase in ACTH release which is followed by an increase in cortisol release?

• infection

• trauma

• intense heat or cold

Cortisol can block inflammation by stabilizing lysosomal membranes to prevent release of proteolytic enzymes.

true

which of these is true about the hormones of the pancreas?

• insulin inhibits glucagon

• amylin inhibits insulin

• somatostatin inhibits insulin and glucagon

insulin promotes fat storage

true

Amine hormones

• thyroxine

• epinephrine

Peptide hormones

• TSH

• LH

• prolactin

• leptin

Steroid hormones

• testosterone

• estrogen

Posterior pituitary

• antidiuretic hormone

• oxytocin

Anterior pituitary hormone

• thyroid stimulating hormone

• luteinizing hormone

• adrenocorticotropin

• growth hormone

• follicle stimulating hormone

• prolactin