Biochemistry of Hormones

What is the main characteristic that determines the control of secretion of a hormone?

Its function (correct)
Its chemical structure
Its chemical properties
Its molecular size

Which class of hormones is derived from the amino acid tyrosine?

Amines (correct)
Eicosanoids
Steroids
Peptides

What is the primary characteristic that distinguishes steroids from other hormones?

Amino acid-based
Water solubility
Peptide-based
Lipid solubility (correct)

What is the primary function of leukotrienes?

Mediating inflammation and allergy reactions (C) Signup and view all the answers

What is the primary characteristic of eicosanoids?

They are biologically active lipids (D) Signup and view all the answers

How do hormones influence target cells?

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

What is the primary function of a receptor in a target cell?

To bind with high affinity to a specific hormone (D) Signup and view all the answers

What is the result of the conversion of the input signal to a biochemical change in the cell?

Induction of gene expression (D) Signup and view all the answers

Where are water-soluble hormones unable to diffuse into?

The interior of the cell (B) Signup and view all the answers

What is the outcome of receptor activation by the input signal?

Conversion of the input signal to a biochemical change (C) Signup and view all the answers

What is the result of the stimulation of synthesis of protein or regulatory molecules?

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

What is the role of second messengers in the conversion of the input signal to a biochemical change?

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

What is the primary function of prolactin in pregnancy and lactation?

Stimulating milk production by the mammary glands (D) Signup and view all the answers

Which hormone inhibits the production of prolactin?

Prolactin-inhibiting hormone (PIH) (C) Signup and view all the answers

What is a common symptom of hyperprolactinemia in females?

Infertility (A) Signup and view all the answers

What is the relationship between estrogen and prolactin levels?

Estrogen stimulates prolactin release (D) Signup and view all the answers

What is a common characteristic of anterior pituitary tumors?

Hyperprolactinemia (B) Signup and view all the answers

What is the primary function of hypothalamic releasing and inhibitory hormones?

To stimulate the release of hormones from the anterior pituitary (A) Signup and view all the answers

Which hormone does not function through a target gland?

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

What is the role of the primary capillary plexus in the hypothalamic-hypophysial portal system?

To transport hypothalamic hormones to the anterior pituitary (C) Signup and view all the answers

What is the effect of hypothalamic hormones on the anterior pituitary?

They stimulate the release of hormones from the anterior pituitary (D) Signup and view all the answers

Which anterior pituitary hormone is derived from the prohormone proopiomelanocortin (POMC)?

Adrenocorticotropic hormone (ACTH) (B) Signup and view all the answers

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

They function through a target gland (A) Signup and view all the answers

What is the mechanism by which insulin is antagonized by glucagon?

Acting through a different metabolic pathway (B) Signup and view all the answers

What is the role of the hypothalamus in regulating the anterior pituitary?

It produces hypothalamic releasing and inhibitory hormones (C) 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 primary function of negative feedback systems in regulating hormone secretion?

To maintain blood levels of hormones within a narrow desirable range (C) Signup and view all the answers

What type of stimulus directly stimulates the secretion of parathyroid hormone (PTH) in response to declining blood Ca2+ concentrations?

Humoral stimulus (B) Signup and view all the answers

What is the role of the sympathetic nervous system in regulating hormone secretion?

Stimulating the adrenal medulla to secrete catecholamines (B) Signup and view all the answers

What is the effect of antagonism on hormone secretion?

Decreases the secretion of the target hormone (C) Signup and view all the answers

What is the term for the interaction of hormones at target cells?

Hormonal interaction (D) Signup and view all the answers