Quiz 2 vocabulary Flashcards
Acidophil
Cells with cytoplasmic granules that stain readily with acid dyes. Acidophils of the anterior pituitary gland secrete prolactin and growth hormone.
Agonist
a substance that can bind to a receptor and act like a native substance resulting in the normal physiologic response
Anastomosis
A communication between two hollow parts, organs or vessels, that are normally separate.
Antagonist
a substance that inhibits the normal action of a hormone or native substance.
Androgen
Hormones with masculinizing properties.
Autocrine communication
When a hormone stimulates the same cell from which it is secreted
Basophil
A group of cells containing granules which stain readily with basic dyes. Basophils of the anterior pituitary gland secrete follicle stimulating hormone and luteinizing hormone
Bioassay
Qualitative or quantitative determination of a substance using living biological material, e.g. rats, mice
Cryptorchidism
Failure of the mammalian testes to descent into the scrotum
Down regulation
decrease in the number of receptors on a target tissue.
Endocrinology
The study of the actions and interactions of the secretions of the endocrine glands
Endocrine secretion
Secretion of a hormone from an endocrine gland which is transported in the blood to a target organ
Endocrine gland
A gland that secretes its product directly into the blood instead into ducts
Endogenous
That which originates within the body.
Enzyme
A protein capable of accelerating some biochemical change in its substrate for which it is usually specific. Enzyme names normally end in “ase (e.g. adenylate cyclase or lipase).
Estrogen
Hormones that promote estrus and stimulate secondary sexual characteristics in females
Exocrine secretion
Secretion of a product into a duct
Exogenous
That which is introduced into the body from outside
Feedback (positive and negative)
a physiological mechanism by which the secretion of a
hormone from a target organ is either inhibited (negative feedback) or stimulated (positive feedback) when the circulating concentration of the hormone attains a specific level
An example of negative feedback
LH from the anterior pituitary gland stimulates progesterone secretion from the corpus luteum. As circulating concentrations of progesterone increase, in the blood, progesterone binds to receptors in the hypothalamus and anterior pituitary gland to decrease the secretion of GnRH and LH, respectively
An example of positive
feedback
H from the anterior pituitary gland stimulates estradiol secretion from the Graafian follicle. As circulating concentrations of estradiol increase in the blood, during the preovulatory period, estradiol binds to receptors in the hypothalamus and anterior pituitary gland to increase the secretion of GnRH and LH, respectively
Glycoprotein
Protein conjugated with a carbohydrate group
Gonad
A primary sex gland, an ovary or testis.
Half life
the time required for one half of a substance (e.g. hormone concentration) to be cleared from the body
Homeostasis
Maintenance of a constant internal environment. This is the goal of physiological mechanisms
Hormone
a chemical signal that is secreted directly into the blood by an endocrine gland and that elicits a physiological response from a target tissue.
Hormone receptor down regulation
a reduction in the number of receptors for a specific hormone
Hypophysectomy
Removal of the hypophysis (pituitary) by surgery.
Hypophysis
Pituitary gland
Hypothalamic nucleus
a collection of nerve cell bodies in a specific location within the hypothalamus that control a physiological response. An example of a hypothalamic nucleus is the tonic center which is a collection of cell bodies of neuroendocrine cells that synthesize GnRH and are responsive to negative feedback in males and females.
Intracrine communication
When a hormone stimulates a cell without being secreted
Kinase
An enzyme that phosphorylates a protein (e.g. Protein kinase)
Ligand
any substance (e.g. protein, hormone, functional group) that binds specifically and reversibly to another chemical entity.
Lipoprotein
A protein conjugated with a lipid
Luteotropin
a hormone or signal that promotes the maintenance and function of a corpus luteum.
Luteolysin
hormone or signal that causes the corpus luteum to regress (luteolysis)
Morphogenesis
The development of form; the development undergone by an organism to approximate to the type of its species.
Morphology
The science of the form and structure of organisms
Neurohormone
a hormone that is secreted directly from a neuron into the blood
Paracrine communication
When a hormone stimulates an adjacent cell without entering the blood.
Phosphorylation
Addition of a phosphate group to a protein. Phosphorylation is an important process for activating or inhibiting the biological activity of a protein.
Physiology
The science which deals with the functions of the living body and its organs.
Progestogen (Progestin)
A hormone that has biological activity similar to progesterone
Signal transduction
a molecular biology term in which a signal outside a cell causes a response inside a cell. An example would be the binding of LH to a cell surface receptor to cause an intracellular increase in cAMP
Steroid
A group name for compounds that chemically resemble cholesterol: sex hormones are members of this group
Steroidogenesis
the synthesis of a steroid by a cell
Synergism
The joint action of two or more hormones or structures so that their combined effect is greater than the sum of their individual affects
