Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

MCAT > Endrocrine System > Flashcards

Endrocrine System Flashcards

(97 cards)

Start Studying
1
Q

Organs of endocrine system are called?

A

Glands

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

Where are hormones secreted into?

A

Bloodstream

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

Do hormones target close or far tissues?

A

Far

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

What are the three chemical identities of hormones?

A
  1. Peptides
  2. Steroids
  3. Amino Acid Derivatives
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Are peptide hormones charged? How does this affect the way they leave and enter cells?

A

Yes - leave cells by exocytosis and then bind to extracellular receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

First and second messengers in peptide hormones

A

First messenger - peptide hormone itself, binds to a receptor and triggers the transmission of a second signal
Second messenger - this second signal triggered by the peptide hormone

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

Examples of second messengers

A

cAMP
IP3
Calcium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What type of hormone is insulin?

A

Peptide hormone

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

What type of hormone is ADH?

A

Peptide hormone

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

What enzyme affects the levels of cAMP?

A

Adenylate cyclase

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

What receptor affects the levels of cAMP?

A

G-protein coupled receptors

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

Are peptide hormone responses fast or slow?

A

Fast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Are peptide hormone responses long or transient?

A

Transient (due to secondary messenger cascades)

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

Are peptide hormones hydrophobic or hydrophilic? How does this affect the way they travel through the body?

A

Hydrophilic - can travel freely in the bloodstream

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

What are steroid hormones derived from?

A

Cholesterol

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

Where are steroids produced?

A

Gonads and adrenal cortex

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

Are steroid hormones charged? How does this affect the way they leave and enter cells?

A

No - they can easily cross the cell membrane and have receptors within the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do steroid receptors do in the cell once bound?

A

Undergo a conformational change and bind directly to DNA

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

Are steroid hormone responses fast or slow?

A

Slow

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

Are steroid hormone responses long or transient?

A

Long

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

Are steroid hormones hydrophobic or hydrophilic? How does this affect the way they travel through the body?

A

Hydrophobic - must travel on proteins through the blood

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

Are steroid hormones active when bound to a carrier protein?

A

No

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

Examples of amino acid derived hormones?

A

Epi

Norepi

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

What are examples of catecholamines?

A

Epi and norepi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What receptors do catecholamines bind to?
G-protein coupled receptors
26
What receptors do thyroid hormones bind to?
Intracellular
27
What are tropic hormones?
Hormones that require an intermediary and do not directly affect the muscle/bone
28
What gland does the hypothalamus have a direct affect on?
Pituitary - anterior and posterior
29
How are the hypothalamus and anterior pituitary connected?
Hypophyseal portal system - release of hormones
30
Where is GnRH released from and what gland and hormone does it affect?
Released from hypothalamus and acts on anterior pituitary to release FSH and LH
31
Where is GHRH released from and what gland and hormone does it affect?
Released from hypothalamus and acts on anterior pituitary to release GH
32
GHRH hormone
Growth-hormone-releasing hormone
33
GnRH hormone
Gonadatropin-releasing hormone
34
Where is TRH released from and what gland and hormone does it affect?
Released from hypothalamus and acts on anterior pituitary to release TSH
35
TRH hormone
Thyroid-releasing hormone
36
TSH hormone
Thyroid-stimulating hormone
37
Where is CRF released from and what gland and hormone does it affect?
Released from hypothalamus and acts on anterior pituitary to release ACTH
38
CRF hormone
Corticotropin releasing factor
39
ACTH hormone
Adrenocorticotropic hormone
40
Where is PIF released from and what gland and hormone does it affect?
Released from hypothalamus and acts on anterior pituitary to decrease prolactin secretion
41
PIF hormone
Dopamine - Prolactin-inhibiting factor
42
Axes in endocrine system
Three-organ systems
43
How are the hypothalamus and posterior pituitary connected?
Neurons in hypothalamus send neurons directly to anterior pituitary
44
What hormones does the posterior pituitary release?
Oxytocin and ADH
45
ADH hormone
Antidiuretic hormone
46
Oxytocin effects
Stimulates uterine contractions, lactation, bonding behavior
47
ADH effects
Increase reabsorption of water in the collecting ducts of kidneys
48
What is ADH secreted in response to in the blood?
Increased blood osmolarity - provides water to decrease this osmolarity
49
Where is prolactin secreted from?
Anterior pituitary
50
What does prolactin do?
Stimulate milk production in the mammary glands
51
How does lactation begin after birth?
Delivery of the placenta leads to a significant decrease in estrogen, progesterone, and dopamine - this (esp dopamine) decrease allows prolactin to stimulate milk production
52
Where are endorphins secreted from?
Anterior pituitary
53
Where is growth hormone secreted from?
Anterior pituitary
54
Acromegaly
Growth of small bones in adults due to effects of lasting growth hormone after the large bones have closed during puberty
55
What hormone has an unusual positive feedback loop?
Oxytocin
56
What are the two main functions of the thyroid?
1. Setting basal metabolic rate | 2. Promoting calcium homeostasis
57
What molecules does the thyroid release to set metabolic rate?
T3 and T4
58
What molecules does the thyroid release to promote calcium homeostasis?
Calcitonin
59
How are T3 and T4 produced?
Iondination of tyrosine
60
Where does Iondination of tyrosine occur?
Follicular cells of thyroid
61
How do increased levels of T3 and T4 affect metabolism?
Increase the rate of cellular respiration and thus increase the rate of synthesis and degradation of proteins and fatty acids
62
Cretinism
Intellectual disability and developmental delay caused by deficiency in thyroid hormones
63
Where in the thyroid is calcitonin produced?
C-cells | Parafollicular cells
64
What does calcitonin do to blood calcium levels?
Decreases
65
How does calcitonin affect blood calcium levels?
1. Increase excretion from kidneys 2. Increasing storage in bones 3. Decreasing calcium absorption in gut
66
PTH hormone
Parathyroid hormone
67
PTH function
1. Raises blood calcium levels (opposite mechanism of calcitonin) 2. Phosphorus homeostasis 3. Activation of vitamin D
68
What is the function of vitamin D?
Absorption of calcium and phosphate in the gut
69
Where are the adrenal glands located?
On top of the kidneys
70
What type of hormone does the adrenal cortex secrete?
Cortiocosteroids
71
Three classes of corticosteroids
Glucocorticoids Mineralocorticoids Cortical sex hormones
72
What is the function of glucocorticoids?
Regulate blood glucose levels and affect protein metabolism
73
Where are glucocorticoids secreted from?
Adrenal cortex
74
What are two glucocorticoids?
Cortisol and cortisone
75
What class of hormones is cortisol?
Glucocorticoid
76
What class of hormones is cortisone?
Glucocorticoid
77
How do cortisol and cortisone function?
Increase glucogenesis and decrease protein synthesis
78
What controls the release of glucocorticoids?
ACTH (which is stimulated by CRF)
79
What is the function of mineralocorticoids?
Affect salt and water homeostasis primarily through the kidney
80
What is an important mineralocorticoid?
Aldosterone
81
What is the function of aldosterone?
Increase sodium and water resorption - osmolarity remains the same, increases blood volume and pressure
82
What is a difference between aldosterone and ADH?
ADH changes blood osmolarity by only affecting water and aldosterone does not by affecting both sodium and water
83
What controls the release of mineralocorticoids?
Renin (kidney) - angiotensin (I to II in the lungs) - aldosterone system
84
Are males or females more sensitive to disorders of cortical sex hormone pathways?
Females - males get a lot of testosterone from the testes and don't rely on the adrenal glands as much as females
85
What class of enzymes are androgens and testosterone?
Cortical sex hormones, corticosteroids, adrenal hormones
86
Where are epi and norepi produced?
Adrenal medulla
87
What two hormones are important to stress response and what are the differences between the two?
Cortisol - long term and slow response | Catecholamines (epi and norepi) - short term and long response
88
What are islets of Langerhans?
Small clusters of hormone-producing cells in the pancreas
89
What types of cells do the islets of Langerhans contain?
Alpha - Glucagon Beta - Insulin Delta - Somatostatin
90
Where specifically is glucagon secreted from?
Alpha cells in the islets of Langerhans in the pancreas
91
Where specifically is insulin secreted from?
Beta cells in the islets of Langerhans in the pancreas
92
Where specifically is somatostatin secreted from?
Delta cells in the islets of Langerhans in the pancreas
93
When is glucagon secreted?
Fasting - increases glucose production
94
Would hyperglycemia be caused by increased or decreased insulin activity?
Decreased
95
What cells would be affected in someone with Type-I diabetes?
Beta cells in the islets of Langerhans in the pancreas
96
What is the function of somatostatin?
Inhibitor of insulin and glucagon
97
What does the pineal gland secrete?
Melatonin

MCAT (31 decks)

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