1.2 Hypothalamus and pituitary gland: Lecture questions
Which hormones are collectively called the gonadotropins?
--Follicle-stimulating hormone --luteinizing hormone
What are the two separate glands that make up the Pituitary gland?
-Adenohypophysis (anterior pituitary gland) -Neurohypophysis (posterior pituitary gland)
The neurohypophysis serves as a storage and release site for what 2 hormones?
-Antidiuretic Hormone (ADH) -Oxytocin (OT)
John tells you that cholesterol is bad and should be eliminated from the diet. You explain to him that cholesterol is important. Whiat hormones are synthesized from cholesterol?
-Estrogen -Progesterone -Androgens (Testosterone)
The Adenohypophysis (anterior pituitary) is divided into what parts?
-Pars distalis (aka: pars anterior): forms the major portion of adenohypophysis) -Pars tuberalis -Pars intermedia
Adenohypophysis cells are more often classified by their secretions of what five types?
-Somatotrophs -Corticotrophs -Thyrotrophs -Lactotrophs -Gonadotrophs
The pars distalis is part of the ______________________.
Adenohypophysis
What promotes and maintains normal growth and development of cortex of adrenal gland; also stimulates adrenal cortex to secrete some of its hormones?
Adrenocorticotropic hormone (ACTH)
Antidiuretic secretion is inhibited by:
Alcohol
Which lobe of the pituitary is larger and secretes more hormones?
Anterior pituitary (adenohypophysis)
What has a secondary effect of increasing blood pressure by stimulating contraction of small arteries?
Antidiuretic hormone (vasopressin)
What prevents the formation of large volumes of urine and also prevents large losses of fluids which helps the body conserve water?
Antidiuretic hormone (vasopressin)
The major targets of growth hormone are ________.
Bones and skeletal muscle
What cells secrete adrenocorticotropid hormone (ACTH)?
Corticotrophs
Which is not correct regarding growth hormone (GH)? A. GH affects most body cells. B. GH stimulates cell growth and mitosis. C. GH is also known as somatotropin. D. GH stimulates the kidney to secrete somatomedin. E. GH is a tropic hormone.
D. GH stimulates the kidney to secrete somatomedin.
Which is not a tropic hormone? A. Thyroid-stimulating hormone B. Adrenocorticotropic hormone C. Follicle-stimulating hormone D. Prolactin
D. Prolactin
A man has been told that he is NOT synthesizing enough follicle-stimulating hormone (FSH), and for this reason he may be unable to father a child. Why would this be? Explain.
FSH stimulates sperm production in the testes.
What secretes luteinizing hormone (LH) and follicle-stimulating hormone (FSH)?
Gonadotrophs
What functions as an insulin antagonist and is vital to maintaining homeostasis of blood glucose levels?
Growth hormone
What promotes growth of bone, muscle, and other tissues by accelerating amino acid transport into the cells?
Growth hormone
What stimulates fat metabolism by mobilizing lipids from storage in adipose cells and speeding up catabolism of the lipids after they have entered another cell?
Growth hormone
Which anterior pituitary hormone does NOT target another endocrine gland?
Growth hormone
Regulating hormones from the hypothalamus first enter the _______________ system.
Hypophyseal portal
Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from hypothalamus to anterior pituitary gland is through the ________.
Hypophyseal portal system
What carries blood from the hypothalamus directly to adenohypophysis where target cells of releasing hormones are located?
Hypophyseal portal system
The pituitary is also called the _____: the anterior portion is the _____, and the posterior portion is the _____.
Hypophysis; Adenohypophysis Neurohypophysis
The hormones that come from the posterior pituitary are synthesized in the _____________ and are released from the posterior pituitary when nerve signals arrive.
Hypothalamus
What secretes releasing hormones into the blood, which are then carried to hypophyseal portal system?
Hypothalamus
Thyrotropin-releasing hormone is secreted by the ______________ and it increases release of thyroid-stimulating hormone from the _____________________.
Hypothalamus; anterior pituitary gland
What is the stemlike stalk that connects pituitary to the hypothalamus?
Infundibulum
The posterior lobe of the pituitary gland is NOT a true endocrine gland because ________.
It is only a hormone storage area. It receives oxytocin and antidiuretic hormone from the hypothalamus.
What secrete prolactin (PRL)?
Lactotrophs
Where is the location of the Pituitary gland?
Located on the ventral surface of the brain within the skull within the sella turcica of the sphenoid bone.
Where are the target cells for follicle-stimulating hormone?
Ovaries and testes
What causes milk ejection from breasts of lactating women?
Oxytocin
What stimulates the contraction of uterine muscle?
Oxytocin
What has traditionally been called the "master gland"
Pituitary gland
Oxytocin release is an example of a ___________ feedback mechanism.
Positive
During pregnancy, what stimulates the mother's mammary glands to produce milk?
Prolactin
What cells secrete growth hormone (GH)?
Somatotrophs
What promotes and maintains growth and development of thyroid; also causes thyroid to secrete its hormones?
Thyroid stimulating hormone
Normal development and activity of the thyroid gland is controlled by _____, a hormone released by the _____.
Thyroid-stimulating hormone (TSH) Anterior pituitary gland (adenohypophysis)
What cells secrete thyroid-stimulating hormone (TSH)?
Thyrotrophs
In which order would blood flow through these structures as it travels from the hypothalamus to the pituitary gland? a: Primary plexus b: Secondary plexus c: Hypophyseal portal veins
a. Primary Plexus. b. Hypophyseal portal veins B. Secondary plexus
Excessive secretion of growth hormone in adults can cause
acromegaly or gigantism/giantism
The pituitary gland is located _________ to the hypothalamus and is connected by the ________.
anterior; infundibulum
The hypothalamic hormone that triggers the release of adrenocorticotropic hormone (ACTH) is
corticotropin-releasing hormone (CRH).
Secretion of growth hormone is primarily regulated by _____ and _____, both of which are released by the _____.
growth hormone releasing hormone (GHRH) Growth hormone inhibiting hormone (GHIH) Anterior pituitary
Within the infundibulum, the axons from neurons extending into the posterior pituitary are known as the
hypothalamo-hypophyseal tract.
Together, the _____ and _____ regulate the secretion of virtually every hormone in the body.
hypothalamus; pituitary
The hypothalamic-hypophyseal tract runs through the __________.
infundibulum
In adults, growth hormone serves to maintain _____.
lean mass
The release of ADH is controlled by _____ in the _____.
osmoreceptors; hypothalamus
Two regions of the hypothalamus that are associated with the posterior pituitary are the:
paraventricular nucleus and supraoptic nucleus.
The hormone oxytocin is synthesized in the
paraventricular nucleus.
The three distinct areas of the anterior pituitary are the:
pars distalis, pars intermedia, and pars tuberalis.
The primary function of adrenocorticotropic hormone (ACTH) is to:
stimulate glucocorticoid release from the adrenal glands.
What is the name for hormones that have a stimulating effect on other endocrine glands?
tropic hormones
Antidiuretic hormone (ADH) promotes _____ by the _____.
water retention; kidneys