Final exam

What is the main function of a primary endocrine gland?

To produce hormones.

What is an antagonist in terms of hormone receptor binding?

A hormone that binds to a receptor without causing a reaction.

What happens to photoreceptors in the dark?

They are depolarized compared to the usual -70 mV.

Which lingual papillae do NOT have taste buds?

Filiform papillae.

What is an example of paracrine secretion?

Hypothalamus secretion to the anterior pituitary gland through blood.

What is the correct pathway of soundwaves through the ear?

Oval window → Scala vestibuli → Cochlear duct → Scala tympani.

What is true about merocrine glands?

Cells in merocrine glands are not altered by the secretory process.

What is NOT a good strategy to treat hormone hypersecretion?

Stimulate the secretion of the hormone.

In the organ of Corti, what do the stereocilia of hair cells contact?

The tectorial membrane.

Where does a lesion suggesting loss of vision on the left side of the visual field for both eyes occur?

The right optic tract (CNS).

What happens to a photoreceptor when stimulated by light?

The photoreceptor becomes hyperpolarized, and voltage-gated Ca2+ channels at the basolateral membrane close.

What happens when someone secretes low levels of growth hormone?

They secrete high levels of GHRH and low levels of IGF-1.

Does the posterior pituitary synthesize ADH?

False. The posterior pituitary releases but does not synthesize ADH.

Are photoreceptors depolarized in darkness?

True.

Do mechanoreceptors detect salty taste?

False. Salty taste is sensed through Na+ channels.

Is the retina highly vascularized?

False.

Can gustatory cells be replaced?

True. Basal cells can replace gustatory cells.

Can an IPSP be initiated by glutamate?

True, depending on the receptor it binds to (e.g., bipolar cells in the retina).

Fill in the blanks: ____ glands secrete through ducts, while ductless ____ glands release ____ into the blood.

Exocrine glands secrete through ducts, while ductless endocrine glands release hormones.

What is the term for a hormone whose presence is required for another hormone to exert its effects?

Permissive.

What happens after light is sensed by photoreceptors?

1. Receptor cells hyperpolarize by closing sodium and calcium channels. 2. The neurotransmitter is not delivered to bipolar cells. 3. Bipolar cells become depolarized. 4. Ganglion cells are activated, sending the signal via the optic nerve.