Biology: Hormones Classification and Functions

What is the primary factor that determines the control of secretion of a hormone?

Its localization
Its molecular size
Its function (correct)
Its chemical class

What is the chemical class of hormones derived from cholesterol?

Peptides
Eicosanoids
Steroids (correct)
Amines

What is the characteristic of eicosanoids?

They are highly localized (correct)
They are water soluble
They have a wide range of effects
They are lipid soluble

What is the function of prostaglandins?

To raise blood pressure, increase uterine contractions, enhance blood clotting, and enhance pain and inflammation (A) Signup and view all the answers

How do hormones influence target cells?

By binding to specific receptors (D) Signup and view all the answers

What is the result of the hormone-receptor interaction?

The hormone initiates a process of transforming the chemical message into a response (B) Signup and view all the answers

What is the role of second messengers in hormone action?

To convert the input signal to a biochemical change in the cell (A) Signup and view all the answers

What is the sequence of events in a target cell responding to a hormone?

Receptor activation, conversion of the input signal, gene expression (A) Signup and view all the answers

Which hormone is not a tropic hormone?

Growth hormone (GH) (D) Signup and view all the answers

What is the primary source of control for the secretion of hormones by the anterior pituitary?

Hypothalamic releasing and inhibitory hormones (C) Signup and view all the answers

What is the role of the hypothalamic-hypophysial portal vessels?

To conduct hypothalamic hormones to the anterior pituitary (B) Signup and view all the answers

What is the effect of growth hormone on the body?

It exerts its effects directly on all or almost all tissues of the body (B) Signup and view all the answers

What is the function of proopiomelanocortin (POMC)?

It is a prohormone that is enzymatically cleaved into other hormones (A) Signup and view all the answers

What is the characteristic of anterior pituitary hormones, except for growth hormone?

They activate cyclic AMP second-messenger systems at their targets (B) Signup and view all the answers

What is the pathway of hormone secretion by the anterior pituitary?

Hypothalamic hormones -> Anterior pituitary -> Target endocrine glands (B) Signup and view all the answers

What is the role of the hypothalamus in the regulation of hormone secretion by the anterior pituitary?

It produces hormones that stimulate or inhibit the release of hormones from the anterior pituitary (D) Signup and view all the answers

What is the primary function of melanocyte-stimulating hormone (MSH) in humans and mammals?

Regulating appetite (B) Signup and view all the answers

What is the effect of growth hormone on the liver?

It increases glycogen breakdown and releases glucose to the blood (D) Signup and view all the answers

What is the role of somatomedins or insulin-like growth factors (IGFs) in growth hormone action?

They are intermediate substances through which growth hormone exerts its effects (B) Signup and view all the answers

What is the effect of growth hormone on the body's use of fatty acids?

It increases the mobilization of fatty acids from adipose tissue (A) Signup and view all the answers

What is the result of growth hormone hypersecretion in children?

Gigantism (C) Signup and view all the answers

What is the function of growth hormone inhibitory hormone (GHIH)?

It inhibits the release of growth hormone (A) Signup and view all the answers

What is the characteristic of growth hormone secretion?

It is secreted in a pulsatile pattern (B) Signup and view all the answers

What is the effect of growth hormone deficiency in children?

Pituitary dwarfism (C) Signup and view all the answers

What is the role of growth hormone-releasing hormone (GHRH) in the regulation of growth hormone secretion?

It stimulates the release of growth hormone (B) Signup and view all the answers

What is the effect of growth hormone on the rate of protein synthesis in most cells of the body?

It increases the rate of protein synthesis (B) Signup and view all the answers

What is the primary function of antidiuretic hormone (ADH)?

To control the rate of water excretion into the urine (A) Signup and view all the answers

Where are the hormones oxytocin and ADH synthesized?

In the hypothalamus (D) Signup and view all the answers

What role does oxytocin play during suckling?

Helps express milk from the breast glands to the nipples (D) Signup and view all the answers

Where are the cell bodies that synthesize posterior pituitary hormones located?

In the hypothalamus's supraoptic and paraventricular nuclei (C) Signup and view all the answers

How are oxytocin and ADH transported from the hypothalamus to the posterior pituitary gland?

Via the axoplasm of nerve fibers (B) Signup and view all the answers

When are oxytocin and ADH released into the blood?

When hypothalamic neurons fire (C) Signup and view all the answers

Which of the following is not a response of a cell to hormonal stimulation?

Formation of new plasma membrane layers (D) Signup and view all the answers

Where are receptors for water-soluble hormones located?

On the plasma membrane (C) Signup and view all the answers

Which of the following is an effect of prolonged high hormone levels on receptors?

Reduction in target cell sensitivity (D) Signup and view all the answers

What happens when a lipid-soluble hormone binds to an intracellular receptor?

Activation or deactivation of enzymes (C) Signup and view all the answers

What induces a more rapid response: lipid-soluble hormones bound to intracellular receptors or plasma membrane receptors?

Plasma membrane receptors (C) Signup and view all the answers

Which of the following factors does not affect target cell activation?

Temperature of the surrounding environment (A) Signup and view all the answers

How do cells compensate for continuous low levels of hormones?

Increase receptor numbers (C) Signup and view all the answers

What is characteristic of receptors in target cells for multiple hormones?

Each hormone exerts a different action (D) Signup and view all the answers