Human Anatomy CH 17 Flashcards
(130 cards)
1
Q
What system interacts closely with the nervous system?
A
Endocrine system
2
Q
What are the organs of the endocrine system and what did they secrete?
A
- Disperse group of ductless glands
- Messenger molecules called hormones
3
Q
What is the study of hormones and endocrine glands?
A
Endocrinology
4
Q
Which 5 endocrine organs are pure endocrine organs?
(HINT: One of them has 2 parts)
A
- Pituitary Gland
- Pineal Gland
- Thyroid Gland
- Parathyroid Gland
- Adrenal Gland - Adrenal Cortex + Adrenal Medulla
5
Q
Which 4 organs contain a large proportion of endocrine cells?
(HINT: Which is specifically part of the brain?)
A
- Pancreas
- Thymus
- Gonads
- Hypothalamus - neuroendocrine organ
6
Q
Which 4 organs contain some endocrine cells? What kind of origin is the endocrine cells?
A
- Heart
- Digestive Tract
- Kidneys
- Skin
Endocrine cells are of epithelial origin
7
Q
What are the 2 classes of hormones? What are they derived from?
A
- Amino acid-based hormones
- Steroids - derived from cholesterol
8
Q
What are 3 basic hormone actions?
A
- Circulate throughout the body in blood vessels
- Influence only specific tissue cells called target cells
- A hormone can have different effects on different target cells
9
Q
Secretion is triggered by what 3 major types of stimuli?
A
- Humoral
- Neural
- Hormonal
10
Q
What 3 things does Humoral stimuli do?
A
- Simplest of endocrine control mechanisms
- Secretion in direct response to changing ion or nutrient levels in the blood
- Parathyroid monitors calcium and responds to decline by secreting hormone to reverse decline
11
Q
What 2 things does Neural stimuli do?
A
- Sympathetic nerve fibers stimulate cells in the adrenal medulla
- Induces release of epinephrine and norepinephrine
12
Q
What 2 things does Hormonal stimuli do?
A
- Stimuli received from other glands
- Certain hormones signal secretion of other hormones
13
Q
The hypothalamus secretes hormones. What do these hormones do?
A
- Stimulate pituitary
- Stimulate other glands
14
Q
What is hormonal secretion controlled by?
A
Feedback loops
15
Q
More hormone is secreted when? Hormone production is halted when?
A
- Blood concentration declines below a minimum
- Blood concentration exceeds maximum
16
Q
What does tropic mean?
A
Hormone causes another gland to release another hormone
17
Q
What are the 9 hormones secreted by the pituitary gland?
A
- FSH
- LH (Luteinizing hormone)
- ACTH (Adrenocorticotropic hormone)
- TSH (Thyroid-Stimulating hormone)
- PRL (Prolactin)
- GH (Growth hormone)
- MSH (Melanocyte-stimulating hormone)
- ADH (Anti-diuretic hormrone)
- Oxytocin
18
Q
The pituitary gland is attached to the hypothalamus via what?
A
Infundibulum
19
Q
What are the 2 basic divisions of the pituitary gland?
A
- Anterior lobe (adenohypophysis)
- Posterior lobe (neurohypophysis)
20
Q
How many divisions does the anterior lobe have? What are they?
A
3 major divisions:
1. Pars distalis
2. Pars intermedia
3. Pars tuberalis
21
Q
How many divisions does the posterior lobe have? What are they?
A
2 major divisions
1. Pars nervosa
2. Infundibulum
22
Q
What is the largest division of the anterior lobe?
A
Pars Distalis
23
Q
The pars distalis contains how many endocrine cells? It makes and secretes how many hormones?
A
Contains 5 different endocrine cells
Makes and secretes 7 different hormones
24
Q
What do tropic hormones do? What 4 hormones are tropic hormones?
A
Regulate hormone secretion by other glands
TSH, ACTH, FSH, and LH
25
What 3 hormones act directly on nonendocrine target tissues?
GH, PRL, and MSH
26
Thyroid-stimulating hormone is produced by what cells? What do these cells do?
1. Thyrotropic cells
2. Signals thyroid gland to secrete thyroid hormone
27
What does adrenocorticotropic hormone do?
Stimulates adrenal cortex to secrete hormones that help cope with stress
28
What do gonadotrophic cells produce? What 2 hormones fall under this category?
Gonadotrophins
1. FSH
2. LH
29
Growth hormone is also known as?
Somatotropic hormone
30
What are the 2 functions of growth hormone?
1. Stimulates body growth by stimulating increased protein production and growth of epiphyseal plates
2. Stimulates growth directly and indirectly by the liver's secretion of insulin-like growth factor-1
31
What does melanocyte-stimulating hormone do in humans?
Appetite suppression
32
Somatotropic cells produce?
Growth hormone (somatotropic hormone)
33
Prolactin is produced by what cells? What does this hormone target and what is its function?
Prolactin cells
Targets milk-producing glands in the breast and stimulates milk production
34
What are endocrine cells in the pars distalis like?
Clustered in spheres and branching cords
35
What are the 5 cell types of the anterior lobe classified as?
(HINT: Only 3 classifications)
1. Acidophils
2. Basophils
3. Chromophobes
36
What controls secretion of anterior lobe hormones?
Hypothalamus
37
What does the hypothalamus secrete to exert control over the anterior lobe? What do these hormones do respectively?
1. Releasing hormones - prompts anterior lobe to release hormones
2. Inhibiting hormones - turns off secretion of anterior lobe hormones
38
Releasing hormones are secreted like?
Neurotransmitters
39
What is the path that releasing hormones travel?
Enters primary capillary plexus ---> travels in hypophyseal portal veins to secondary capillary plexus ----> hormones secreted by anterior lobe enter general circulation and travels to target organs
40
Is the posterior lobe of pituitary gland structurally part of the brain?
Yes
41
What do the axons of the posterior lobe make up?
Hypothalamohypophyseal tract
42
The hypothalamohypophyseal tract arises from what and in which part of the body?
Neuronal cell bodies in the hypothalamus
43
What 2 types of regions of the hypothalamus make up the hypothalamohypophyseal?
1. Supraoptic nucleus
2. Paraventricular nuclear
44
What are the 2 main functions of the posterior lobe? What does it NOT do?
1. Stores and releases hormones made in hypothalamus
2. Does not make hormones
45
What 2 peptide hormones does the posterior lobe release?
1. ADH
2. Oxytocin
46
What is another name for ADH that is NOT antidiuretic hormone?
Vasopressin
47
Where is ADH made? What is its function?
1. Supraoptic nucleus
2. Targets kidneys to resorb water
48
Where is oxytocin made? What is its function?
1. Paraventricular nucleus
2. Induces smooth muscle contraction of reproductive organs, ejects milk during breast-feeding, and signals contraction of the uterus during childbirth
49
What is the largest purely endocrine gland? Where is it located?
Thyroid Gland; located in anterior neck
50
What is the thyroid gland composed of? What 2 hormones does it produce?
Composed of follicles and areolar connective tissue
1. Thyroid Hormone (TH)
2. Calcitonin
51
Where are the parathyroid glands?
Lie on posterior surface of thyroid gland
52
What are the 2 types of endocrine cells that the parathyroid glands produce? What are their functions?
1. Chief cells - Produce parathyroid hormone (PTH) and increases blood concentration of Ca2+
2. Oxyphil cells - function unknown
53
What are the pyramid-shaped glands located on the superior surface of each kidney called?
Adrenal (suprarenal) glands
54
The adrenal glands are supplied by how many suprarenal arteries?
60 suprarenal arteries
55
The Adrenal gland's nerve supply is almost exclusively _______
sympathetic fibers
56
What is the cluster of neurons in the adrenal glands? What is it derived from and what system is it a part of?
Adrenal Medulla
Derived from: Neural crest
Part of sympathetic nervous system
57
What do all adrenal hormones help with?
Helps body cope with danger, terror, or stress
58
What forms the bulk of the adrenal gland? What is it derived from?
Adrenal Cortex
Derived from: Somatic mesoderm
59
What are modified postganglionic sympathetic neurons called?
Medullary chromaffin cells
60
Medullary chromaffin cells secrete what type of hormones?
(HINT: There's 2 of them)
Amine hormones
1. Epinephrine
2. Norepinephrine
61
What do epinephrine and norepinephrine do? Where are they stored?
Enhances "fight-or-flight" response
Stored in secretory vesicles
62
How are epinephrine and norepinephrine arranged and stored?
Arranged in spherical clusters and some branching cords
63
What does the Adrenal Cortex secrete? What is the alternate name for them?
Secretes lipid-based steroid hormones
Corticosteroids
64
What are the 3 layers (zones) of the adrenal cortex? How is each one arranged?
1. Zona glomerulosa - cells arranged in spherical clusters
2. Zona fasciculata - cells arranged in parallel cords
3. Zona reticularis - cells arranged in branching network
65
What are the 2 main classes of adrenal corticosteroids?
1. Mineralocorticoids
2.Glucocorticoids
66
What is a mineralocorticoid that is secreted by the zona glomerulosa?
Aldosterone
67
Aldosterone is secreted in response to?
In response to decline in blood volume or blood pressure
68
Aldosterone is the terminal hormone of what mechanism?
Terminal hormone of renin-angiotensin mechanism
69
Which adrenal cortex zone contains lipid droplets?
Zona fasciculata
70
What is the main type of glucocorticoid?
Cortisol
71
What 2 zones of the adrenal cortex secretes cortisol?
1. Zona fasciculata
2. Zona reticularis
72
What does the cortisol help with?
Helps body deal with stressful situations
73
What is the small pinecone-shaped gland called? Where is it located?
Pineal Gland located on roof of diencephalon
74
What within the pineal gland is arranged in spherical clusters and branching cords? What do they secrete?
Pinealocytes; secretes melatonin
75
What is a characteristic of "pineal sand"?
Radiopaque
76
What is pineal sand used for?
Used as a landmark to identify other brain structures in X-ray films
77
What is melatonin used for?
Regulates circadian rhythm
78
What is located in the posterior abdominal wall?
Pancreas
79
What kind of cells does the pancreas contain?
(HINT: There's 2)
Endocrine and exocrine cells
80
What is another name for exocrine cells of the pancreas? What does it secrete?
Acinar cells - secretes digestive enzymes
81
What is another name for endocrine cells of the pancreas? How many are there?
Pancreatic islets
About 4 million islets
82
What are the 2 main cell types of the pancreas? What do they secrete?
Alpha cells - secrete glucagon
Beta cells - secrete insulin
83
What are the 2 main functions of glucagon?
1. Signals liver to release glucose from glycogen
2. Raise blood sugars
84
What are the 3 main functions of insulin?
1. Signal most body cells to take up glucose from the blood
2. Promote storage of glucose as glycogen in liver
3. Lower blood sugars
85
What are the 2 rare cell types found in pancreatic islets? What do they secrete?
Delta cells - secrete somatostatin
F cells - secrete pancreatic polypeptide
86
What is the function of somatostatin?
Inhibits secretion of insulin and glucagon
87
What is the function of pancreatic polypeptide?
May inhibit exocrine activity of the pancreas
88
What is located in the lower neck and anterior thorax?
Thymus
89
Is the thymus an important immune organ?
Yes
90
The thymus is the site at which what occurs?
Site at which T lymphocytes arise from precursor cells
91
The transformation of _______ is stimulated by _________
The transformation of lymphocytes is stimulated by thymic hormones
92
Thymic hormones are also known as?
Peptide molecules
93
What are 2 types of thymic hormones?
1. Thymopoietin
2. Thymosin
94
The gonads are the main sources of ________. What are the 2 main gonads?
Sex hormones
1. Ovaries
2. Testes
95
What disorder is the hypersecretion of GH in children?
Gigantism
96
What disorder is the hyposecretion of GH?
Pituitary Dwarfism
97
What disorder is when the pars nervosa doesn't release enough ADH?
Diabetes insipidus
98
What kind of disorders do Gigantism, Pituitary Dwarfism, and Diabetes Insipidus fall under?
Pituitary Disorders
99
What endocrine organ does diabetes affect?
Pancreas
100
What is Diabetes Mellitus caused by?
(HINT: 2 causes)
1. Insufficient secretion of insulin
2. Resistance of body cells to the effects of insulin
101
What disorder is when a T cell-mediated autoimmune response destroys beta cells?
Type 1 Diabetes
102
When does Type 1 diabetes develop?
Develops suddenly, usually before age 15
103
What disorder is when cells have lowered sensitivity to insulin?
Type 2 Diabetes
104
When does Type 2 diabetes develop?
Adult onset, usually occurs after age 40
105
What can help control Type 2 diabetes?
Dietary changes and regular excercise
106
What is the most common type of hyperthyroidism?
Graves' Disease
107
What happens when someone if afflicted with Graves' disease?
Immune system makes abnormal antibodies which stimulate the oversecretion of TH by follicle cells
108
What are the symptoms of Graves' disease?
Nervousness, weight loss, sweating, and rapid heart rate
109
What is the disorder known for adult hyperthyroidism?
Myxedema
110
What happens when someone is afflicted with Myxedema?
Antibodies attack and destroy thyroid tissue
111
What are common symptoms of Myxedema?
Low metabolic rate and weight gain
112
What disorder is due to lack of iodine in the diet?
Endemic goiter
113
What is hypothyroidism in children called?
Cretinism
114
What are the symptoms of Cretinism?
Short, disproportionate body, thick tongue, and mental retardation
115
What disorder is caused by hypersecretion of glucocorticoid hormones?
Cushing's Syndrome
115
Graves' Disease, Myxedema, Endemic goiter, and Cretinism are all disorders of what gland?
Thyroid Gland
116
Addison's disease is what kind of disorder? What is it a deficiency of?
Addison's Disease; deficiency of mineralocorticoids and glucocorticoids
117
Cushing's Syndrome and Addison's Disease are both caused by what part of the endocrine system?
Adrenal Cortex
118
Where does the thyroid gland form from?
Forms from thickening of endoderm on floor of pharynx
119
Where does the parathyroid and thymus gland form from?
Forms from endoderm lining the pharyngeal pouches
120
What does the pineal gland originate from?
Originates from ependymal cells
121
Where does the pituitary gland originate from?
(HINT: One for adenohypophysis and one for neurohypophysis)
1. Adenohypophysis originates from roof of mouth
2. Neurohypophysis grows inferiorly from floor of brain
122
Where does the adrenal gland originate from?
(HINT: One for adrenal medulla and one for adrenal cortex)
1. Adrenal Medulla - From neural crest cells of nearby sympathetic trunk ganglia
2. Adrenal Cortex - From mesodermal lining of coelum
123
For how long does the endocrine organs function for within the human lifespan?
Operates effectively until old age
124
As the anterior pituitary ages, what happens to it?
(HINT: 2 things occur)
1. Increase in connective tissue and lipofuscin
2. Decrease in vascularization and number of hormone-secreting cells
125
As the adrenal cortex ages, what happens to it?
Normal rates of glucocorticoid secretion continue
126
As the adrenal medulla ages, what happens to it?
No age-related changes in catecholamines
127
As the thyroid hormones age, what happens to it?
Decreases slightly with age
128
As the parathyroid glands age, what happens to it?
Little change with aging
129
As FH, DHEA, and sex hormones age, what happens to them?
Marked drops in secretion with age
