Which of the following describes an endocrine communication?
A) Works rapidly across very short distances
B) Structurally related to each other and their target organs
C.) Duration of action is very brief
D.) Chemical messenger is carried over long distances in the blood
E.) Coordinates very precise responses
Hydrophilic hormone binding to a receptor with multiple transmembrane domains and which activates, via an effector protein, a second messenger system within the target cell is characteristic of a:
A.) G-protein coupled receptor
B.) Tyrosine kinase receptor
C.) Chemically gated receptor channel
D.) depolarization
e.) Hormone response element
Which of the following describes a lipophilic hormone?
A.) Secreted as it is synthesized
B.) Does not use transport proteins in the blood
C.) Acts solely through receptors located at the cell membrane
D.) Acts predominantly through second messenger systems
E.) Initially synthesized as a preprohormone
Which of the following would contribute to a rise in plasma hormone concentration?
A.) Increased amounts of binding proteins
B.) Increased secretion rate
C.) Reduced activation/conversion of the inactive hormone
D.) Increased metabolism/clearance
E.) Reduced secretion of the hormone
The situation where the output of a system opposes the input is:
A.) Antagonism
B.) Permissiveness
C.) Synergism
D.) Negative feedback
E.) Positive feedback
Which of the following is NOT true about a circadian rhythm?
A.) Driven by the suprachiasmatic nucleus
B.) Occurs with a periodicity of every hour
C.) Involves self-starting clock proteins
D.) Can be synchronized by the environment
E.) Periodicity is influenced by melatonin
The posterior pituitary:
A.) Is functionally, but not anatomically connected to the hypothalamus
B.) Secretes tropic hormones in response to releasing hormones
C.) Derived from Rathke’s pouch
D.) Secretes hormones originally produced in neurons of the paraventricular nucleus
E.) Is a major source of growth hormone
Which of the following is NOT true about vasopressin?
A.) Decreased osmolarity is the biggest stimulus for its release
B.) Released in response to a large decrease in atrial volume
C.) Inserts aquaporins into kidney collecting tubules to increase water retention
D.) Has a pressor effect via arteriolar smooth muscle
E.) Release triggered by exertion in a hot environment
Growth hormone:
A.) Acts through IGF-1 to exert its metabolic effects
B.) Increases fat deposition
C.) Inhibits protein synthesis
D.) Acts through IGF-1 to influence bone growth
E.) Acts through IGF-2 to influence metabolism
Bone formation is characterized by:
A.) Multiplication of osteocytes at the epiphysis edge of epiphyseal plate
B.) Clearing of dead cells by osteocytes
C.) Stimulation of osteoblast activity by growth hormone
D.) Deposition of new bone by osteocytes
E.) Addition of surface bone by chondrocytes in the periosteum
Abnormally stunted growth, very high GH concentrations, and yet an absence of a response to GH are characteristic of:
A.) Acromegaly
B.) Laron Dwarfism
C.) Normal Dwarfism
D.) Pygmieism
E.) Hyposecretion of GH during adulthood
Which of the following is NOT essential for growth?
A.) Thyroid Hormone
B.) Insulin
C.) Androgens
D.) IGF-1
E.) Cortisol
Development along the female pathways depends upon
A.) Contribution of a Y chromosome from the paternal side
B.) Presence of testosterone
C.) Presence of DHT
D.) Nothing, it’s the default pathway for sexual development
E.) Wolffian duct development
Which of the following is most directly due to SRY?
A.) Genetic sex
B.) Gonadal sex
C.) Phenotypic sex
D.) Mullerian duct development
E.) Ovarian development
Which is a function of the Sertoli Cell?
A.) Secretes testosterone
B.) Freely allows passage of immune cells into lumen
C.) Secretes inhibin to specifically suppress GnRH
D.) Secretes Mullerian inhibiting factor
E.) Capacitation
Which of the following is part of the erectile mechanism?
Increased sympathetic input
Decreased parasympathetic input
Increased venous drainage
Increased nitric oxide metabolism
A spinal reflex
The second meiotic division in the oocyte occurs:
A.) Prior to birth
B.) Immediately after birth
C.) During the final stages of follicular development
D.) During the LH surge
E.) Upon fertilization by the sperm
The LH surge is due to:
A.) Increase progesterone from the follicle
B.) High levels of estradiol from the follicle
C.) Increased inhibin from the follicle
D.) The act of intercourse
E.) Low levels of estradiol from the follicle
Which of the following is true of human chorionic gonadotropin (hCG)?
A.) Lyses the corpus luteum of pregnancy
B.) Stimulates Sertoli cell production of testosterone
C.) Activates relaxin, which is important for parturition
D.) Is LH-like in function
E.) Necessary for placental progesterone production in late pregnancy
Which describes the role of estrogen in the initiation of parturition?
A.) Stimulates CRH release from the placenta
B.) Stimulates IL-8 from the uterus
C.) Inhibits pulmonary surfactant protein secretion
D.) Decreases prostaglandin secretion
E.) Increases myometrium oxytocin receptors
Which of the following inside the pancreas beta cell would lead to insulin secretion?
A.) Blockage of GLUT2
B.) Blockade of ATP generation
C.) Hyperpolarization of the cell
D.) Closure of Ca++ channels
E.) Phosphorylation of Glucose
Which of the following would be stimulatory to insulin release?
A.) Decreased glucose in blood
B.) Decreased parasympathetic input
C.) Decreased amino acids in blood
D.) Decreased sympathetic input
E.) Decreased incretin release
Which of the following would be a treatment for type 2 diabetes?
A.) Inhibition of beta-cell function
B). Stimulation of glycogenolysis
C.) Increasing sensitivity to glucagon
D.) Inhibiting the incretins
E.) Inhibiting dipeptidyl peptidase, which metabolizes GLP-1
Which of the following is true about glucagon?
A.) Stimulated by increased glucose
B.) Usually elevated during diabetes
C.) Enforces the actions of insulin
D.) Stimulated by somatostatin
E.) Causes significant hyperglycemia when hypersecreted