ENDOCRINE (FINALS) Flashcards
1
Q
Hormones control several major processes:
A
- Reproduction
- Growth and development
- Mobilization of body defenses
- Maintenance of much of homeostasis
- Regulation of metabolism
2
Q
are chemical substances secreted by endocrine cells into the extracellular fluids that regulate the metabolic activity of other cells in the body
A
hormones
3
Q
hormone come from a Greek word meaning ____
A
“to arouse”
4
Q
Amino acid-based hormones (3)
A
Proteins
Amines
Peptides
5
Q
made from cholesterol include the sex hormones made by the gonads (ovaries and testes)
A
steroids
6
Q
made from highly active lipids
A
Prostaglandins
7
Q
MECHANISMS OF HORMONE ACTION
A
Target cells or organs
Receptor
8
Q
- Hormones affect only certain tissues or organs
- must have specific protein receptors
A
Target cells or organs
9
Q
which that hormone can attach must be present on the cell’s plasma membrane or in its interior
A
Receptor
10
Q
STEROID HORMONE ACTION
Diffuse through the _______
A
plasma membrane of target cells
11
Q
STEROID HORMONE ACTION (6)
A
- Enter the nucleus
- Bind to a specific protein within the nucleus
- Bind to specific sites on the cell’s DNA
- Activate genes that result in synthesis of new proteins
- The mRNA is translated in the cytoplasm
- Resulting in the synthesis of new proteins
12
Q
Hormone binds to a membrane receptor and does not enter the cell
A
NONSTEROID HORMONE ACTION
13
Q
Hormone levels in the blood are maintained by _________
A
negative feedback
14
Q
Hormone release stops once an ________ in the blood is _______.
A
appropriate level in the blood is reached
15
Q
Endocrine glands are activated by other hormones
A
Hormonal Stimuli of Endocrine Glands
15
Q
Changing blood levels of certain ions and nutrients stimulate hormone release
A
Humoral Stimuli of Endocrine Glands
15
Q
The term _____ refers to the ancient use of the word humor to indicate the various body fluids (blood, bile, and others)
A
humoral
15
Q
- Nerve impulses stimulate hormone release
- Most are under control of the sympathetic nervous system
A
Neural Stimuli of Endocrine Glands
16
Q
MAJOR ENDOCRINE ORGANS
A
o Pituitary
o Pineal
o Parathyroid
o Thymus
o Adrenal
o Pancreas
o Gonads (ovaries and testes)
o Hypothalamus
16
Q
Controls the release and inhibits the hormones of the pituitary glands
A
HYPOTHALAMUS
17
Q
Liberates regulatory hormones into the blood of the portal circulation, which connects blood supply of the hypothalamus with the anterior pituitary gland
A
HYPOTHALAMUS
18
Q
Makes oxytocin and Antidiuretic hormone
A
HYPOTHALAMUS
19
Q
- Size of a grape
- “master endocrine gland”
- Hangs by a stalk from the hypothalamus snugly surrounded by sella turcica
- Protected by the sphenoid bone
A
PITUITARY GLAND
20
Q
two functional lobes of pituitary gland:
A
- Anterior pituitary – glandular tissue
- Posterior pituitary – nervous tissue
21
General metabolic hormone
GROWTH HORMONE (GH)
21
Characteristics of all anterior pituitary hormones
- Proteins (or peptides)
- Act through second-messenger systems
- Regulated by hormonal stimuli, mostly negative feedback
21
Major effects are directed to growth of skeletal muscles and long bones
GROWTH HORMONE (GH)
21
Six (6) anterior pituitary hormones
2 affect non-endocrine targets
4 stimulate other endocrine glands (tropic hormones)
22
Causes amino acids to be built into proteins and Causes fats to be broken down for a source of energy
GROWTH HORMONE (GH)
22
- Stimulates and maintains milk production following childbirth
- Function in males is unknown
Prolactin (PRL)
23
Regulates endocrine activity of the adrenal cortex
Adrenocorticotropic hormone (ACTH)
23
Influences growth and activity of the thyroid
Thyroid-stimulating hormone (TSH) or thyrotropic hormone (TH)
23
Regulate hormonal activity of the gonads
Gonadotropic hormones
23
Stimulates testosterone production in males (referred to as interstitial cell-stimulating hormone (ICSH))
Luteinizing hormone (LH)
23
- Stimulates follicle development in ovaries and sperm development in testes
- they produce estrogen as follicles mature
Follicle-stimulating hormone (FSH)
23
- Stimulates contractions of the uterus during labor, sexual relations and during breastfeeding
- Causes milk ejection (let-down reflex
Oxytocin
23
- triggers ovulation
- causes ruptured follicle to become the corpus luteum
Luteinizing hormone (LH)
24
- Can inhibit urine production
- In large amounts, causes vasoconstriction leading to increased blood pressure (vasopressin)
Antidiuretic hormone (ADH)
25
- Found at the base of the throat just inferior to the Adam’s apple
- Consists of two lobes joined by central mass or isthmus
THYROID GLAND
26
Thyroid gland produces two hormones:
1. Thyroid hormone
2. Calcitonin
26
Calcitonin is produced by __________
parafollicular gland
26
Thyroid is composed of two active iodine-containing hormones:
1. Thyroxine (T4)
2. Triiodothyronine (T3)
26
Major metabolic hormone
THYROID HORMONE
27
secreted by thyroid follicles
Thyroxine (T4)
28
conversion of T4 at target tissues
Triiodothyronine (T3)
29
important for normal tissue growth and development, especially in the reproductive and nervous systems
THYROID HORMONE
29
Controls the rate at which glucose is “burned,” or oxidized, and converted to body heat and chemical energy (ATP)
THYROID HORMONE
30
Decreases blood calcium levels by causing its deposition on bone (hypocalcemic)
CALCITOCIN
31
Antagonistic to parathyroid hormone
CALCITOCIN
32
Calcitocin is produced by __________
C (parafollicular) cells
33
It is released directly to the blood in response to an increasing level of blood calcium ions.
Calcitocin
34
Tiny masses on the posterior of the thyroid
that secrete parathyroid hormone
PARATHYROID GLANDS
35
function of parathyroid hormone:
o Stimulate osteoclasts to remove calcium from bone and release it into the blood
o Stimulate the kidneys and intestine to absorb more calcium
o Raises calcium levels in the blood (hypercalcemic)
36
Located posterior to the sternum in upper thorax and is largest in infants and children. It also produces thymosin
THYMUS
37
function of thymosin
o Matures some types of white blood cells
o Important in developing the immune system
38
glands that curve on top of the kidney like triangular hats
ADRENAL GLANDS
39
two glands in adrenal glands
1. Cortex
2. Medulla
40
outer glandular region in three layers
cortex
40
inner neural tissue region
medulla
41
3 major groups of steroid hormones (corticosteroids)
1. Mineralocorticoids (mainly aldosterone)
2. Glucocorticoids (including cortisone and cortisol)
3. Sex hormones
42
- Produced in outer adrenal cortex
- Regulate mineral content in blood, water, and electrolyte balance
Mineralocorticoids
42
o Promote normal cell metabolism
o Control the more unpleasant effects of inflammation by decreasing edema, and they reduce pain by inhibiting the pain-causing prostaglandins
Glucocorticoids
43
- Produced in the inner layer of the adrenal cortex
- Androgens (male) and some estrogen (female)
Sex hormones
44
Produces two similar hormones (catecholamines) when stimulated by sympathetic nervous system
HORMONES OF THE ADRENAL MEDULLA
45
hormones of the adrenal medulla produces two similar hormones (catecholamines) which are:
1. Epinephrine (adrenaline)
2. Norepinephrine (noradrenaline)
46
These hormones prepare the body to deal with short-term stress
catecholamines/hormones of the adrenal medulla
47
The islets of the pancreas (islets of Langerhans) produce hormones:
1. Insulin
2. Glucagon
48
allows glucose to cross plasma membranes into cells from beta cells
insulin
49
These hormones are antagonists that maintain blood sugar homeostasis
islets of the pancreas
50
allows glucose to enter the blood from alpha cells. Its primary target organ is the liver, which it stimulates to break down stored glycogen to glucose and to release the glucose into the blood.
glucagon
51
A small, coneshaped gland that hangs from the roof of the third ventricle of the brain that secretes melatonin
PINEAL GLAND
52
Helps establish the body’s wake and sleep cycles or the “sleep trigger”
melatonin
53
Produces sex cells (exocrine) and sex hormones (endocrine)
GONADS
54
are paired, slightly larger than almond-sized organs located in the pelvic cavity.
Ovaries
55
Paired oval glands suspended in the scrotum outside the pelvic cavity
Testes
56
- Produced by Graafian follicles of the ovaries or the placenta
Estrogens
57
- Produced by the corpus luteum
- Acts with estrogen to bring about the menstrual cycle
Progesterone
58
____ of testes are hormone - producing
Interstitial cells
59
____ is the most important androgen
Testosterone
60
function of testosterone
- Responsible for adult male secondary sex characteristics
- Promotes growth and maturation of male reproductive system
- Required for sperm cell production
61
produced by the developing embryo and then by the fetal part of the placenta
Human Chorionic Gonadotropin (hCG)
62
works cooperatively with estrogen and progesterone in preparing the breasts for lactation
Human Placental Lactogen
62
causes the mother’s pelvic ligaments and the pubic symphysis to relax and become more flexible, which eases birth passage
Relaxin
62
ENDOCRINE FUNCTION OF THE PLACENTA
- Produces hormones that maintain the pregnancy
- play a part in the delivery of the baby
- Produces human chorionic gonadotropin (HCG)
63
OTHER HORMONE-PRODUCING TISSUES AND ORGANS
- Parts of the small intestine
- Parts of the stomach
- Kidneys
- Heart
- Placenta – temporary organ
- Some tumors
- Many other areas have scattered endocrine cells
64
Stimulates the development of secondary female characteristics
estrogen
65
Helps prepare the uterus to receive a fertilized egg and maintain pregnancy
estrogen
66
Stimulates the ovaries to continue producing estrogen and progesterone so that the lining of the uterus is not sloughed off in menses
Human Chorionic Gonadotropin (hCG)
67
Helps in the implantation of an embryo in the uterus
and helps prepare breast tissue for lactation
progesterone
67
it quiets the muscles of the uterus so that an implanted embryo will not be aborted
progesterone
67
Glucocorticoids help resist _____ stressors
long-term
68
_______ is released in response to increased blood levels of ACT
Glucocorticoids
68
______ is produced in the middle layer of the adrenal cortex
Glucocorticoids
