Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIO 207- Human Physiology > Exam 4- Chapter 11 > Flashcards

Exam 4- Chapter 11 Flashcards

1
Q

Describe the structure of endocrine glands and where the secrete their hormones.

A

ductless and secrete hormones into bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where do the hormones of endocrine glands travel to?

A

Hormones travel to target cells that contain receptor proteins for it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Neurohormones

A

secreted into blood by specialized neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Hormones affect _____ of targets.

A

metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 4 types of hormones?

A
  1. Amine hormones
  2. Polypeptide and protein hormones
  3. Glycoproteins
  4. Steroids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are amine hormones derived from?

A

tyrosine or tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do amine hormones include?

A
  1. NE
  2. Epi
  3. thyroxine
  4. melatonin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are polypeptide and protein hormones chains of?

A

amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do polypeptide and protein hormones include?

A

Include ADH, GH, insulin, oxytocin, glucagon, ACTH, PTH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What do glycoprotiens include?

A

LH, FSH, TSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are steroids derived from?

A

lipids derived from cholesterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What do steroids include?

A
  1. testosterone
  2. estrogen
  3. progesterone
  4. alsoterone
  5. cortisol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

____ and ____ hormones are lipids.

A
  1. Steroid

2. thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Since steroids and thyroid hormones are lipids what does this allow for?

A

Can diffuse into target cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the two major thyroid hormones?

A
  1. Thyroxine (T4)

2. Triiodothyronine (T3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Prohormones/Give example.

A

precursors of hormones/proinsulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Prehormones/Give example.

A

precursors of prohormones/preproinsulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q
  1. Some hormones are inactive until activated by ___ ____.

2. Give an example of this

A
  1. Target Cells

2. Thyroxine (T4) is inactive until converted to T3 in target cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Both NS and endocrine system use chemicals to communicate. Difference between NTs and hormones is what?

A

Difference between NTs and hormones is transport in blood and more diversity of effects in hormone targets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Can some chemicals be used as hormones and NTs?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Do targets for NTs have specific receptor proteins?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Do targets for hormones have specific receptor proteins?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

There must be a ___ way to inactivate NTs and Hormones.

A

Rapid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Does a tissue have a specific hormone it responds to?

A

NO; tissue usually responds to # of hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Synergistic Hormones.

A

work together to produce an effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Do synergistic hormones produce a larger effect together or when the individual effects are added together?

A

Produce a larger effect together than individual effects added together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Permissive effect.

A

enhances responsiveness of a target organ to 2nd hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Antagonistic hormone.

A

action of 1 hormone inhibits effect of another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Half- Life.

A

time required for blood level to be reduced by half

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the range of a half-life?

A

Ranges from mins to hrs for most (days for thyroid hormones)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Normal tissue responses are produced only when hormones are in _____ range.

A

physiological

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

High (pharmacological) doses of hormones can cause # of side effects. Why?

A

Probably by binding to receptors of different but closely related other hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is another name for the priming effect?

A

Up-regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is another name for desensitization?

A

downregulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

When does the Priming effect (upregulation) occur? What does it result in?

A
  1. when a hormone induces more of its own receptors in target cells
  2. Results in greater response in target cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

When does desensitization (downregulation) occur?

A

occurs after long exposure to high levels of polypeptide hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

With desensitization (down regulation) what happens with subsequent exposure to the hormone? Why?

A
  1. Subsequent exposure to this hormone produces a lesser response
  2. Due to decrease in # of receptors on target
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Most peptide hormones have pulsatile secretion which ____ ____.

A

prevents downregulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Target cell receptors show what 3 characteristics for a hormone?

A
  1. specificity
  2. high affinity
  3. low capacity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Where do lipophilic hormones have receptors, and why?

A

Lipophilic hormones have receptors in target’s cytoplasm and/or nucleus because can diffuse thru plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q
  1. What is the target of lipophilic hormones and what do they affect there?
  2. What is this called and how long does it usually take?
A
  1. Their target is the nucleus where they affect transcription
  2. Genomic action and takes at least 30 mins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Where are the receptors for hydrophilic hormones?

A

surface of target cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What system to hydrophilic hormones act through and are they fast or slow? What is this called?

A
  1. These act through 2nd messengers; effects are quick

2. Nongenomic action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Even though steroids are lipophilic and enter the target cells, what do some steroids act on?

A

Some steroids also act on cell surface receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Generally how do lipid hormones enter the target cell?

A
  1. Lipid hormones travel in blood attached to carrier proteins
  2. They dissociate from carriers to pass thru plasma membrane of target
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are the receptors for lipid hormones called?

A

nuclear hormone receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What do nuclear hormone receptors serve as when bound to hormone ligands? What do they do when this happens?

A
  1. transcription factors

2. Activate transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Nuclear hormone receptors constitute a “superfamily”, what is this composed of?

A
  1. Steroid family

2. Thyroid hormone family (which includes vitamin D and retinoic acid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What does the thyroid hormone family include?

A

vitamin D and retinoic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What are the 2 domains of nuclear hormone receptors?

A
  1. Ligand (hormone)-binding domain

2. DNA-binding domains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

When the hormone binds to the nuclear hormone receptor, what does the receptor then bind to?

A

hormone-response element (HRE) on DNA located adjacent to target gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What does the HRE consist of?

A

2 half-sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Mechanisms of Steroid Hormones:

What stimulates the transcription of the target gene? What is this called?

A
  1. 2 ligand-bound receptors have to bind to each HRE

2. Dimerization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Mechanism of Thyroid Hormone Action:

What 2 hormones does the thyroid secrete and what is the percentage of each?

A

Thyroid secretes 90% T4 (thyroxine) and 10% T3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Mechanism of Thyroid Hormone Action:

99.96% of T4 in blood is bound to carrier protein, what is this carrier protein called?

A

thyroid binding globulin (TBG)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Mechanism of Thyroid Hormone Action:

What can enter the cell?

A

Only free thyroxine and T3 can enter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Mechanism of Thyroid Hormone Action:

Protein bound thyroxine serves as a ______.

A

reservoir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Mechanism of Thyroid Hormone Action:

What happens to T4 inside the target cell?

A

T4 converted to T3 inside target cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Mechanism of Thyroid Hormone Action:

What happens to T3 (and the T4 that was converted into T3) inside the target cell?

A

T3 binds to receptor protein located in nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Mechanism of Thyroid Hormone Action:

Describe what happens after T3 is bound to its receptor.

A
  1. T3 and receptor bind to 1 half-site
  2. Other half-site binds retinoic acid
  3. Two partners form heterodimer that activates HRE
  4. Stimulates transcription of target gene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is different about the mechanism of steroid hormones and thyroid hormones?

A

Steroid hormones bind to both receptors and then to the half sites while with thyroid hormones, thyroid hormone binds to one with retinoic acid binds to the other.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What type of hormones use 2nd messengers?

A

Water soluble hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Which receptors do water soluble hormones use, and why?

A

Water soluble hormones use cell surface receptors because cannot pass through plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

The actions of water soluble hormones are mediated by what?

A

by 2nd messengers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

In the mechanism of water soluble hormones what is the extracellular signal? What carries the signal from the receptor to inside the cell?

A
  1. Hormones = extracellular signal

2. 2nd messengers carry signal from receptor to inside of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What are the 3 second messenger systems used with hormones?

A
  1. Adenylate Cyclase-cAMP
  2. Phospholipase-C-Ca2+
  3. Tryosine Kinase 2nd messenger system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

cAMP mediates effects of many ____ and _____ hormones.

A
  1. polypeptide

2. glycoprotein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Describe the mechanism of the Adenylate Cyclase-cAMP 2nd messenger system.

A
  1. Hormone binds to receptor causing dissociation of a G-protein subunit
  2. G-protein subunit binds to and activates adenylate cyclase
    • This converts ATP into cAMP
  3. cAMP attaches to inhibitory subunit of protein kinase
  4. Inhibitory subunit dissociates, activating protein kinase
    - This phosphorylates enzymes that produce hormone’s effects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What is cAMP inactivated by?

A

phosphodiesterase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Describe the mechanism of the Phospholipase-C-Ca2+ 2nd messenger system.

A
  1. Hormone binds to surface receptor and activates G-protein; which activates phospholipase C
  2. Phospholipase C splits a membrane phospholipid into 2nd messengers IP3 and DAG
  3. IP3 diffuses through cytoplasm to ER
    • This causes Ca2+ channels to open
  4. Ca2+ diffuses into cytoplasm and binds to and activates calmodulin
  5. Ca2+-Calmodulin activates protein kinases which phosphorylate enzymes that produce hormone’s effects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Which 2nd messenger system does epinephrine act by?

A

TWO:

  1. Adenylate Cyclase-cAMP 2nd messenger system
  2. Phospholipase-C-Ca2+ 2nd messenger system
72
Q

What is the Tryosine Kinase 2nd messenger system used by, and what does it cause?

A

Is used by insulin and many growth factors to cause cellular effects

73
Q

Describe the mechanism of the Tryosine Kinase 2nd messenger system.

A
  • Surface receptor is tyrosine kinase
    1. Consists of 2 units that form active dimer when insulin binds
    2. Activated tyrosine kinase phosphorylates signaling molecules that induce hormone/growth factor effects
74
Q

What is the surface receptor for the ryosine Kinase 2nd messenger system?

A
  • Surface receptor is tyrosine kinase
75
Q

Insulin stimulates glucose uptake by means of what?

A

GLUT 4 carrier proteins

76
Q

After insulin binds to tyrosine kinase, and activates the Tryosine Kinase 2nd messenger system what happens?

A

2nd messengers cause vesicles containing GLUT4 transporters to be inserted into plasma membrane

77
Q

Where is the pituitary gland located?

A

beneath hypothalamus at base of forebrain

78
Q

How is the pituitary gland divided?

A

structurally and functionally divided into anterior and posterior lobes

79
Q

The pituitary gland hangs below hypothalamus by the ______.

A

infundibulum

80
Q

What is the function of the anterior pituitary gland?

A

Produces own hormones that are controlled by hypothalamus

81
Q

What is the function of the posterior pituitary gland?

A

Posterior stores and releases hormones made in hypothalamus

82
Q

What hormones does the posterior pituitary gland store/release that were made in the hypothalamus?

A
  1. Oxytocin

2. Vasopressin (ADH/AVP)

83
Q

How many and what type of hormones does the anterior pituitary gland secrete?

A

Secretes 6 trophic hormones that maintain size of targets

84
Q

High blood levels of the anterior pituitary hormones cause the target to ____.

A

hypertrophy (increase volume)

85
Q

Low blood levels of the anterior pituitary hormones cause the target to ____.

A

atrophy (decrease volume)

86
Q

What are the names of the 6 anterior pituitary hormones?

A
  1. Growth Hormone (GH)
  2. Thyroid Stimulating Hormone (TSH)
  3. Adrenocorticotrophic Hormone (ACTH)
  4. Follicle Stimulating Hormone (FSH)
  5. Luteinizing Hormone (LH)
  6. Prolactin (PRL)
87
Q 
What is the function of the:
Growth Hormone (GH)
A
  1. promotes growth
  2. promotes protein synthesis
  3. promotes movement of amino acids into cells
88
Q

What is the function of the:

Thyroid Stimulating Hormone (TSH)

A

stimulates thyroid to produce and secrete:

  1. T4
  2. T3
89
Q 
What is the function of the:
Adrenocorticotrophic Hormone (ACTH)
A

stimulates adrenal cortex to secrete:

  1. cortisol
  2. aldosterone
90
Q

What is the function of the:

Follicle Stimulating Hormone (FSH)

A
  1. stimulates growth of ovarian follicles

2. stimulates sperm production

91
Q 
What is the function of the:
Luteinizing Hormone (LH)
A
  1. causes ovulation

2. causes secretion of testosterone in testes

92
Q

What is the function of the:

Prolactin (PRL)

A

stimulates milk production by mammary glands

93
Q

What is the release of anterior pituitary hormones controlled by?

A
  1. hypothalamic releasing and inhibiting factors

2. feedback from levels of target gland hormones

94
Q

Describe how the hypothalamic releasing and inhibiting factors control the anterior pituitary.

A
  1. Releasing and inhibiting hormones from hypothalamus are released from axon endings into capillary bed in median eminence
  2. Carried by hypothalamo-hypophyseal portal system directly to another capillary bed in A. Pit.
  3. Diffuse into A. Pit. and regulate secretion of its hormones
95
Q

The hypothalamic-pituitary-gonad axis (control system) involves what 3 types of “loops”?

A
  1. Short feedback loop
  2. Negative feedback loop
  3. Positive feedback loop
96
Q

Describe the short feedback loop of the hypothalamic-pituitary-gonad axis (control system).

A

retrograde flow of blood and hormones from A. Pit. to hypothalamus inhibits secretion of releasing hormone

97
Q

Describe the negative feedback loop of the hypothalamic-pituitary-gonad axis (control system).

A

negative feedback of target gland hormones

98
Q

Describe the positive feedback loop of the hypothalamic-pituitary-gonad axis (control system).

A

during menstrual cycle, estrogen stimulates “LH surge” by positive feedback

99
Q

What input do higher brain centers have in anterior pituitary secretion?

A

Hypothalamus receives input from higher brain centers that can affect A. Pit. secretion

100
Q

What is an example of higher brain centers having input in anterior pituitary secretion?

A

emotional states and psychological stress can affect circadian rhythms, menstrual cycle, and adrenal hormones

101
Q

What is the function of Vasopressin (ADH/AVP)?

A

promotes H2O conservation by kidneys

102
Q

What is the function of oxytocin?

A
  1. Stimulates contractions of uterus during parturition

2. Stimulates contractions of mammary gland alveoli for milk-ejection reflex

103
Q

What part of the hypothalamus produces ADH?

A

Supraoptic nuclei of hypothalamus

104
Q

What part of the hypothalamus produces oxytocin?

A

Paraventricular nuclei of hypothalamus

105
Q

How is ADH/Vasopressin and Oxytocin transported from the hypothalamus to the posterior pituitary?

A

Both transported along hypothalamo-hypophyseal tract to posterior pituitary

106
Q

What is the release of the posterior pituitary controlled by?

A

Release controlled in hypothalamus by neuroendocrine reflexes

107
Q

Where do the adrenal glands sit on? What do the adrenal glands structurally consist of?

A
  1. Sit on top of kidneys

2. Each consists of outer cortex and inner medulla

108
Q

Do the outer cortex and inner medulla of the adrenal cortex arise the same during development?

A

NO; arise differently during development

109
Q

What 2 hormones does the inner medulla of the adrenal cortex synthesize/secrete (how much % of each)? What is this controlled by?

A
  1. 80% Epinephrine and 20% Norepinephrine

2. Sympathetic division of ANS

110
Q

What is the adrenal cortex controlled by?

111
Q

What does the adrenal cortex secrete?

A
  1. Cortisol
  2. Aldosterone
  3. Some supplementary sex steroids
112
Q

What is the function of:

Cortisol

A

inhibits glucose utilization and stimulates gluconeogenesis

113
Q

What is the function of:

Aldosterone

A

stimulates kidneys to reabsorb Na+ and secrete K+

114
Q

Do the hormonal effects of epinephrine or norepinephrine last longer, and by how much?

A

Hormonal effects of Epinephrine last 10X longer than Norepinephrine

115
Q

What is the adrenal medulla innervated by?

A

preganglionic Sympathetic fibers

116
Q

When is the adrenal medulla activated?

A

“fight or flight” response

117
Q

What does the activation of the adrenal medulla cause?

A
  1. Increased respiratory rate
  2. Increased HR and cardiac output
  3. General vasoconstriction which increases venous return
  4. Glycogenolysis and lipolysis
118
Q

What does stress induce? What does this cause?

A
  1. Stress induces a non-specific response called general adaptation syndrome (GAS)
  2. Causes ACTH and cortisol release
119
Q

When stress induces GAS and causes ACTH and corstisol release, what type of feedback loop is this?

A

Negative feedback loop

120
Q

Chronic stress can induce high levels of cortisol that cause a number of ___ ____.

A

negative effects

121
Q

What are 4 negative effects that chronic stress and the high levels of cortisol that it induces cause?

A
  1. atrophy of hippocampus (involved in memory)
  2. reduced sensitivity of tissues to insulin (insulin resistance)
  3. inhibition of vagus nerve activity
  4. suppression of growth hormone, thyroid hormone, and gonadotropins
122
Q

Where is thyroid gland located?

A

just below the larynx

123
Q

What does the thyroid gland secrete, and what is the function of these hormones?

A

Secretes T4 and T3:

  1. Set BMR
  2. Needed for growth and development
124
Q

The thyroid gland consist of microscopic ____ ___.

A

thyroid follicles

125
Q

The thyroid gland consist of microscopic thyroid follicles.

  1. What does the outer layer consist of and what is the function?
  2. What is the interior filled with?
A
  1. Outer layer is follicle cells that synthesize T4

2. Interior filled with colloid, a protein-rich fluid

126
Q

Describe the production and secretion of the thyroid hormones.

A
  1. Iodide (I-) in blood is actively transported into follicles and secreted into colloid
  2. In the colloid it is oxidized to iodine (I2) and attached to tyrosines of thyroglobulin
  3. TSH stimulates hydrolysis of T4 and T3s from thyroglobulin and then secretion
127
Q

What is thyroglobulin?

A

A large storage molecule for T4 and T3

128
Q

What exactly does TSH do in the thyroid gland?

A

TSH stimulates hydrolysis of T4 and T3s from thyroglobulin and then secretion

129
Q

What are 3 diseases of the thyroid?

A
  1. Goiter
  2. Hypothyroidism
  3. Hyperthyroidism
130
Q

Describe what happens with Goiter (disease of the thyroid).

A
  1. In absence of sufficient dietary iodide, T4 and T3 cannot be made and levels are low
  2. Low T4 and T3 don’t provide negative feedback and TSH levels go up
  3. Because TSH is a trophic hormone, thyroid gland grows
    resulting in a goiter
131
Q

People with inadequate T4 and T3 levels are what?

A

hypothyroid

132
Q

People who are hypothyroid have what?

A
  1. low BMR
  2. weight gain
  3. lethargy
  4. cold intolerance
  5. myxedema
133
Q

What is myxedema?

A

puffy face, hands, feet

134
Q

During fetal development what can hypothyroidism cause?

A

cretenism (severe mental retardation)

135
Q

Goiters are also produced by what?

A

Grave’s disease

136
Q

What is Grave’s disease?

A

Autoimmune disease where antibodies act like TSH and stimulate thyroid gland to grow and oversecrete = hyperthyroidism

137
Q

What is Grave’s disease/Hyperthyroidism characterized by?

A
  1. exopthalmos
  2. weight loss
  3. heat intolerance
  4. irritability
  5. high BMR
138
Q

Where are the parathyroid glands located?

A

embedded in lateral lobes of post. side of thyroid gland

139
Q

What do the parathyroid glands secrete?

A

Parathyroid hormone (PTH)

140
Q

What is the function of the Parathyroid hormone (PTH)?

A

Most important hormone for control of blood Ca2+ levels

141
Q

What is the release of the Parathyroid hormone (PTH) stimulated by?

A

Release stimulated by decreased blood Ca2+

142
Q

What does the Parathyroid hormone (PTH) act on?

A

Acts on bones, kidney, and intestines to increase blood Ca2+ levels

143
Q

What type of feedback loop does the PTH work on?

A

negative feedback loop

144
Q

What are the Islets of Langerhans?

A

Are scattered clusters of endocrine cells in pancreas

145
Q

What type of cells do the Islets of Langerhans contain?

A

Contain alpha and beta cells

146
Q

What do the alpha cells of the Islets of Langerhans secrete and in response to what?

A

Alpha cells secrete glucagon in response to low blood glucose

147
Q

When the alpha cells of the Islets of Langerhans secrete glucagon what does this stimulate?

A

Stimulates glycogenolysis and lipolysis:

which increases blood glucose

148
Q

What do the beta cells of the Islets of Langerhans secrete and in response to what?

A

insulin in response to high blood glucose

149
Q

Describe the mechanism of the beta cells of the Islets of Langerhans.

A
  1. Beta cells secrete insulin in response to high blood glucose
  2. Promotes entry of glucose into cells and conversion of glucose into glycogen and fat
  3. Decreases blood glucose
150
Q

Where is the pineal gland located?

A

basal forebrain near thalamus

151
Q

What does the pineal gland secrete and in response to what?

A

Secretes melatonin in response to activity of suprachiasmatic nucleus (SCN) of hypothalamus

152
Q

What is the primary timing center for circadian rhythms?

A

suprachiasmatic nucleus (SCN)

153
Q

How often and by what is the suprachiasmatic nucleus (SCN) reset?

A

Reset by daily light/dark changes

154
Q

What is melatonin involved in?

A

aligning physiology with sleep/wake cycle and seasons

155
Q

When is melatonin secreted/inhibited?

A

Secreted at night and is inhibited by light

156
Q

When is melatonin implicated?

A

Implicated in jet-lag

157
Q

Which GI tract organs produce hormones?

A
  1. Stomach
  2. Small intestine
  3. (Pancreas?)
158
Q

What do the hormones of the small intestine act on?

A

Act on GI tract itself, gallbladder, and pancreas

159
Q

The hormones of the small intestine act in convert with what? What is the function of this?

A
  1. ANS

2. To coordinate regions of GI tract and pancreatic juice and bile

160
Q

What hormones do the gonads secrete (testes and ovaries)?

A

steroid hormones:

  1. testosterone
  2. estrogen
  3. progesterone
161
Q

What hormones does the placenta secrete?

A
  1. estrogen
  2. progesterone
  3. hCG
  4. somatomammotropin
162
Q

Autocrine regulators.

A

produced and act within same tissue of an organ

163
Q

All autocrines control ___ ____in target cells.

A

gene expression

164
Q

Paracrine regulators.

A

autocrines that are produced within one tissue and act on different tissue in same organ

165
Q

Autocrines and paracrines include:

A
  1. Cytokines (lymphokines, interleukins)
  2. Growth factors (promote growth and cell division)
  3. Neutrophins (provides trophic support for normal and regenerating neurons)
166
Q

What are examples of Cytokines?

A

lymphokines & interleukins

167
Q

What do growth factors do?

A

promote growth and cell division

168
Q

What is the function of neutrophins?

A

provides trophic support for normal and regenerating neurons

169
Q

Where are Prostaglandins (PGs) produced?

A

Are produced in almost every organ

170
Q

What family do Prostaglandins (PGs) belong to? What is everything in this family derived from?

A

Belong to eicosanoid family – all derived from arachidonic acid of plasma membrane

171
Q

Prostaglandins (PGs) have a ____ variety of functions.

172
Q

Lists 4 functions of Prostaglandins (PGs).

A
  1. Different PGs may exert antagonistic effects in tissues
  2. Promotes inflammatory process of immune system
  3. Plays role in ovulation
  4. Inhibits gastric secretion in digestive system
173
Q

Different PGs may exert antagonistic effects in tissues. Give 2 examples of this.

A
  1. Some promote smooth muscle contraction and some relaxation
  2. Some promote clotting; some inhibit
174
Q

What is involved in PG synthesis?

A

Cyclooxygenase (COX) 1 and 2

175
Q

Cyclooxygenase (COX) 1 and 2 are targets of a number of what?

A

inhibitory non-steroidal anti-inflammatory drugs (NSAIDs)

176
Q

Aspirin, indomethacin, ibuprofen inhibit what?

A

both COX 1 and 2 thereby producing side effects

177
Q

Celebrex and Vioxx inhibit what?

A

only inhibit COX 2 and thus have few side effects in the gastric mucosa

BIO 207- Human Physiology (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions