Endocrine System Flashcards
1
Q
Second controlling system of the body
A
Endocrine system
2
Q
What system is the fast-control system?
A
Nervous system
3
Q
The endocrine system uses chemical messengers called ___ that are released into the blood.
A
Hormones
4
Q
Hormones control which major processes?
A
Reproduction
Growth and development
Mobilization of body defenses
Maintenance of much of homeostasis
Regulation of metabolism
5
Q
What hormones are used in reproduction?
A
Follicle-stimulating hormone
Luteinizing hormone
6
Q
What hormone is used in growth and development?
A
Growth hormone
7
Q
Hormones are produced by ___.
A
Specialized cells
8
Q
Cells secrete hormones into ____.
A
Extracellular fluids
9
Q
Blood transfers hormones to ___.
A
Target sites
10
Q
The scientific study of hormones and endocrine organs.
A
Endocrinology
11
Q
What are the four chemical classifications of hormones?
A
Amino-acid based
Steroids
Prostaglandins
12
Q
Amino acid-based hormones include ___.
A
Proteins, peptides, and amines
13
Q
Catecholamines (ex. dopamine, epinephrine, norepinephrine) are examples of what chemical classification of hormones?
A
Amines
14
Q
What hormones are commonly used to treat inflammation?
A
Steroids
15
Q
What hormones are examples of steroids?
A
Sex hormones (estrogen, progesterone, testosterone)
16
Q
These type of hormones are made from cholesterol
A
Steroids
17
Q
These are made from highly active lipids that act as local hormones.
A
Prostaglandins
18
Q
These hormones serve as chemical mediators
A
Prostaglandins
19
Q
Hormones act by what two mechanisms?
A
Direct gene activation and second messenger system
20
Q
True or False: Hormones affect only certain tissues or organs.
A
TRUE. They are called target cells or target organs.
21
Q
Target cells must have ___.
A
Specific protein receptors
22
Q
What happens when cells are aroused by hormones?
A
- Changes in plasma membrane permeability or electrical state
- Synthesis of proteins, such as enzymes
- Activation or inactivation of enzymes
- Stimulation of mitosis
- Promotion of secretory activity
23
Q
What is the order of direct gene activation?
A
- Steroid hormones diffuse through the plasma membrane of target cells
- Steroid hormones enter the nucleus
- Steroid hormones bind to a specific protein within the nucleus
- Hormone-receptor complex binds to specific sites on the cell’s DNA
- Certain genes are activated that result in…
- Synthesis of new proteins
24
Q
Direct gene activation is also known as ___.
A
Steroid hormone action
25
What is the order of second-messenger system?
1. Hormone (first messenger) binds to a membrane receptor
2. Activated receptor sets off a series of reactions that activates an enzyme
3. Enzyme catalyzes a reaction that produces a second-messenger molecule (such as cyclic AMP, or cAMP)
4. Oversees additional intracellular changes to promote a specific response in the target cell
26
Second-messenger system is also called ___.
Nonsteroid hormone action
27
Hormone levels in the blood are maintained mostly by ___.
Negative feedback
28
What triggers the release of more hormones?
A stimulus or low hormone levels in the blood
29
How does hormone release stop?
Once an appropriate level in the blood is reached.
30
Stimuli that activate endocrine glands fall into what three major categories?
Hormonal
Humoral
Neural
31
What is the most common stimulus?
Hormonal
32
It is when endocrine organs are activated by other hormones.
Hormonal stimuli
33
Anterior pituitary hormones travel to target glands (ex. thyroid gland) to prompt release of a particular hormone (ex. thyroid hormone). This is an example of what endocrine stimulus?
Hormonal stimuli
34
It is when changing blood levels of certain ions and nutrients stimulate hormone release.
Humoral stimuli
35
It indicates various bodily fluids (ex. blood & bile)
Humoral
36
Parathyroid hormone and calcitonin are produced in response to changing levels of blood calcium levels, and insulin is produced in response to changing levels of blood glucose. This is an example of what type of endocrine stimuli?
Humoral stimuli
37
True or False: Nerve impulses stimulate hormone release.
TRUE
38
Most are under the control of what subdivision of the autonomic nervous system?
Sympathetic nervous system
39
The release of norepinephrine and epinephrine by the adrenal medulla is an example of what type of endocrine stimuli?
Neural stimuli
40
What are the major endocrine organs?
Pituitary gland
Thyroid gland
Parathyroid gland
Adrenal glands
Pineal gland
Thymus gland
Pancreas
Gonads (ovaries & testes)
Hypothalamus
41
They are ductless glands.
Endocrine glands
42
What glands are purely endocrine?
Anterior pituitary
Thyroid
Parathyroid
Adrenals
43
Where are hormones released?
Directly into blood or lymph
44
They are glands with both endocrine and exocrine functions.
Mixed glands
45
What are examples of mixed glands?
Pancreas and gonads
46
How large is the pituitary gland?
The size of a pea
47
The pituitary hangs by a stalk from what part of the brain?
Hypothalamus
48
What bone protects the pituitary gland?
Sphenoid bone
49
What are the two lobes of the pituitary gland?
Anterior pituitary
Posterior pituitary
50
The anterior pituitary is made of ___ tissue, while the posterior pituitary is made of ___ tissue.
Glandular; nervous
51
It is often called the "master endocrine gland"
Pituitary gland
52
What type of hormones are released by the hypothalamus?
Releasing & inhibiting hormones; oxytocin and antidiuretic hormone
53
What connects hypothalamus to anterior pituitary?
Portal circulation
54
Where are oxytocin and antidiuretic hormone stored?
Posterior pituitary
55
What carries oxytocin and antidiuretic hormone to the posterior pituitary?
Neurosecretory cells
56
Stimulates contractions of the uterus during labor, sexual relations, and breastfeeding
Oxytocin
57
Causes milk ejection (let-down reflex) in a breastfeeding woman
Oxytocin
58
Inhibits urine production by promoting water reabsorption by the kidneys
Antidiuretic hormone
59
Urine production is also known as ___.
Diuresis
60
True or False: In large amounts, causes vasoconstriction of arterioles, leading to increased blood pressure.
TRUE. This is why ADH is known as vasopressin.
61
What inhibits ADH secretion?
Alcohol
62
What results from ADH hyposecretion?
Diabetes insipidus
63
How many hormones are produced by the anterior pituitary?
Six
64
What are the anterior pituitary hormones?
1. Growth hormone
2. Prolactin
3. Thyroid-stimulating hormone
4. Adrenocorticotropic hormone
5. Follicle-stimulating hormone
6. Luteinizing hormone
65
Thyroid-stimulating hormone is also known as ___.
Thyrotropic hormone
66
What hormones of the anterior pituitary affect nonendocrine targets?
1. Growth hormone
2. Prolactin
67
These hormones stimulate other endocrine glands to release hormones.
Tropic hormones
68
What anterior pituitary hormones are tropic?
1. Thyroid-stimulating hormone
2. Adrenocorticotropic hormone
3. Follicle-stimulating hormone
4. Luteinizing hormone
69
What are the characteristics of all anterior pituitary hormones?
Protein (or peptides) structure
Act through second-messenger
systems
Regulated by hormonal stimuli
Regulated mostly by negative
feedback
70
It is the general metabolic hormone.
Growth hormone (GH)
71
Major effects of GH are directed to ___.
Growth of skeletal muscles and long bones
72
Plays a role in determining final
body size
Growth hormone (GH)
73
Causes amino acids to be built into proteins
Growth hormone (GH)
74
Causes fats to be broken down for a source of energy
Growth hormone (GH)
75
This disorder results from hyposecretion of GH during childhood.
Pituitary dwarfism
76
This disorder results from hypersecretion of GH during childhood.
Gigantism
77
This disorder results from hypersecretion of GH during adulthood.
Acromegaly
78
This hormone stimulates and maintains milk production following childbirth.
Prolactin (PRL)
79
What is the function of prolactin in males?
It is unknown
80
This hormone regulates endocrine activity of the adrenal cortex.
Adrenocorticotropic hormone (ACTH)
81
This hormone influences growth and activity of the thyroid gland.
Thyrotropic hormone (TH), or thyroid stimulating hormone (TSH)
82
These hormones regulate hormonal activity of the gonads.
Gonadotropic hormones
83
What are the gonadotropic hormones?
Follicle-stimulating hormone (FSH)
Luteinizing hormone (LH)
84
Stimulates follicle development in ovaries
Follicle-stimulating hormone (FSH)
85
Triggers ovulation of an egg in females
Luteinizing hormone (LH)
86
Stimulates sperm development in testes
Follicle-stimulating hormone (FSH)
87
Stimulates testosterone production in males
Luteinizing hormone (LH)
88
Where can the thyroid gland be found?
At the base of the throat
89
Consists of two lobes and a connecting isthmus
Thyroid gland
90
What hormones are produced by the thyroid gland?
1. Thyroid hormone
2. Calcitonin
91
It is the major metabolic hormone.
Thyroid hormone
92
Controls rate of oxidation of glucose to supply body heat and chemical energy.
Thyroid hormone
93
Needed for tissue growth and development
Thyroid hormone
94
Thyroid hormone is composed of what two active iodine containing hormones?
Thyroxine (T4)
Triiodothyronine (T3)
95
It is secreted by thyroid follicles
Thyroxine (T4)
96
conversion of T4 at target tissues
Triiodothyronine (T3)
97
This disorder is when thyroid gland enlarges because of lack of iodine.
Goiters
98
What is iodized to prevent goiters?
Salt
99
Caused by hyposecretion of
thyroxine, and results in dwarfism during childhood.
Cretinism
100
Caused by hypothyroidism in adults, and results in physical and mental sluggishness
Myxedema
101
Caused by hyperthyroidism, and results in increased metabolism, heat intolerance, rapid heartbeat, weight loss, and exophthalmos
Graves’ disease
102
This hormone decreases blood calcium levels by causing calcium deposition on bone.
Calcitonin
103
Calcitonin is antagonistic to ____.
Parathyroid hormone
104
Calcitonin is produced by ___.
Parafollicular cells found between the follicles
105
Tiny masses on the posterior of the thyroid.
Parathyroid glands
106
What do parathyroid glands secrete?
Parathyroid hormone (PTH)
107
Stimulates osteoclasts to remove calcium from bone
Parathyroid hormone (PTH)
108
Hypercalcemic hormone (increases blood calcium levels)
Parathyroid hormone (PTH)
109
Stimulates the kidneys and intestine to absorb more calcium
Parathyroid hormone (PTH)
110
These glands sit on top of the kidneys.
Adrenal glands
111
What are the two regions of the adrenal glands?
Adrenal cortex and adrenal medulla
112
Outer glandular region that has three layers
Adrenal cortex
113
These are secreted by the outermost layer of the adrenal cortex.
Mineralocorticoids
114
These are secreted by the middle layer of the adrenal cortex.
Glucocorticoids
115
These are secreted by the innermost layer of the adrenal cortex.
Sex hormones
116
Regulate mineral content in blood, particularly sodium and potassium ions.
Mineralocorticoids
117
Mineralocorticoids are mostly ___.
Aldosterone
118
Regulate water and electrolyte balance.
Mineralocorticoids
119
What is the target organ of mineralocorticoids?
Kidneys
120
What stimulates the release of aldosterone?
Humoral factors (fewer sodium ions or too many potassium ions in the blood)
Hormonal stimulation (ACTH)
Renin and angiotensin II in response to a drop in blood pressure
121
A hormone produced by the heart when blood pressure is too high
Atrial natriuretic peptide (ANP)
122
What inhibits aldosterone production?
Atrial natriuretic peptide (ANP)
123
Promote normal cell metabolism
Glucocorticoids (including cortisone and
cortisol)
124
Help resist long-term stressors by increasing blood glucose levels (hyperglycemic hormone)
Glucocorticoids (including cortisone and
cortisol)
125
Produced by the middle layer of the adrenal cortex and has anti-inflammatory properties.
Glucocorticoids (including cortisone and
cortisol)
126
Released in response to increased blood levels of ACTH
Glucocorticoids (including cortisone and
cortisol)
127
Male sex hormones are also called ___.
Androgens
128
Female sex hormones are also called ___.
Estrogens
129
True or False: Mostly androgens are made in the adrenal cortex, but some
estrogens are also formed.
TRUE
130
This disorder results from hyposecretion of all adrenal cortex hormones.
Addison’s disease
131
What are the effects of Addison's disease?
Bronze skin tone, muscle weakness, burnout, susceptibility to infection
132
This disorder may result from an ACTH-releasing tumor.
Hyperaldosteronism
133
Excess water and sodium are retained, leading to high blood pressure and edema
Hyperaldosteronism
134
This disorder results from a tumor in the middle cortical area of the adrenal cortex.
Cushing’s syndrome
135
What are the effects of Cushing’s syndrome?
“Moon face,” “buffalo hump” on
the upper back, high blood pressure, hyperglycemia, weakening of bones, depression
136
This disorder results from hypersecretion of sex hormones.
Masculinization
137
What are the effects of masculinization?
Beard and male distribution of hair growth
138
What are the hormones produced by the adrenal medulla?
Epinephrine (adrenaline)
Norepinephrine (noradrenaline)
139
How do epinephrine and norepinephrine prepare the body to deal with short-term stress (“fight or flight”)?
Increasing heart rate, blood pressure, blood glucose levels
Dilating small passageways of lungs
140
Where is the pancreas located?
in the abdomen, close to the stomach
141
What hormones are produced by the pancreatic islets?
Insulin and glucagon
142
True or False: Insulin and glucagon are antagonists that maintain blood calcium homeostasis.
FALSE. They maintain blood glucose homeostasis.
143
Insulin is produced by ___ cells, while glucagon is produced by ___ cells.
beta; alpha
144
Released when blood glucose levels are high
Insulin
145
Released when blood glucose levels are low
Glucagon
146
Stimulates the liver to release glucose to blood, thus increasing blood glucose levels.
Glucagon
147
Increases the rate of glucose uptake and metabolism by body cells.
Insulin
148
What occurs in the absence of insulin?
Diabetes mellitus
149
Blood sugar levels increase dramatically, and blood glucose is lost in the urine; water follows.
Diabetes mellitus
150
What are the three cardinal signs of diabetes mellitus?
Polyphagia, polyuria, polydipsia
151
Where is the pineal gland located?
posterior to the third ventricle of the brain
152
What is secreted by the pineal gland?
Melatonin
153
This hormone helps establish the body’s sleep/wake cycles as well as biological rhythms.
Melatonin
154
True or False: Melatonin is believed to coordinate the hormones of fertility in humans
TRUE
155
Where is the thymus gland located?
Posterior to the sternum
156
True or False: The thymus gland is largest in adults.
FALSE. It is largest in infants and children.
157
This hormone matures some types of white blood cells, and is important in developing the
immune system.
Thymosin
158
Thymosin is produced by the ___.
Thymus gland
159
What are the gonads?
Ovaries and testes
160
Ovaries produce ___ cells, while testes produce ___ cells.
Egg; sperm
161
Ovaries produce the hormones ___, while testes produce the hormone ___.
Estrogens and progesterone; androgens (ex. testosterone)
162
These hormones stimulate the development of secondary female characteristics, and mature female reproductive organs.
Estrogens
163
Acts with estrogen to bring about the menstrual cycle, helps in the implantation of an embryo in the uterus, and helps prepare breasts for lactation.
Progesterone
164
With progesterone, estrogens also ___.
Promote breast development and regulate menstrual cycle
165
What is the most important androgen?
Testosterone
166
Responsible for adult male secondary sex characteristics, promotes growth and maturation of male reproductive system, and is required for sperm cell production.
Testosterone
167
What are other hormone-producing tissues and organs?
▪ Parts of the small intestine
▪ Parts of the stomach
▪ Kidneys
▪ Heart
▪ Many other areas have scattered endocrine cells
168
Produces hormones that maintain pregnancy.
Placenta
169
What hormones are produced by the placenta?
Human chorionic gonadotropin
(hCG) in addition to estrogen,
progesterone, and other hormones
170
True or False: In the absence of disease, efficiency of the endocrine system remains high until middle age.
FALSE. It remains high until old age.
171
True or False: Efficiency of all endocrine glands gradually increases with aging.
FALSE: Efficiency decreases with aging.
172
Efficiency decrease of endocrine glands with age can lead to ___.
▪ Diabetes mellitus
▪ Immune system depression
▪ Lower metabolic rate
▪ Cancer rates in some areas
