Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biology for the MCAT :) > Endocrine System > Flashcards

Endocrine System Flashcards

(69 cards)

Start Studying
1
Q

Glands

A

Secrete hormones

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

Hormones

A

Signaling molecules / messengers secreted directly into the bloodstream to travel distant target tissues inducing a change in gene expression or cellular functioning

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

Peptide Hormones

A
  • Made up of amino acids (peptides and proteins)
  • Transported to the golgi apparatus for modifications that activate the hormone and are released by exocytosis to the correct location to bind to extracellular receptor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

First Messenger

A

Peptide Hormones:
Hormone binds to receptor and triggers the second messenger (second signal)

  • IP3
  • Ca
  • cAMP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Signaling Cascade

A

Peptide Hormones:

Overall effect and a possibility of each step having amplification or increasing intensity of the signal

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

Steroid Hormones

A
  • Derived from cholesterol
  • Nonpolar molecules allow movement across the cell membrane - receptors are usual intracellular or intranuclear
  • Bind to DNA to alter gene transcription (alter mRNA and protein amounts)
  • Slower Effets but Last Longer
  • Carried by protein (not water soluble)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Amino Acid Derived Hormones

A

Derived from 1-2 amino acids with a few additional modifications (less predictable hormones)

Similar to Peptide Hormones:

  • Epinephrine
  • Norepinephrine

Similar to Steroid Hormones:

  • T3
  • T4
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Catecholamines

A
  • Bind to G-protein coupled receptors
  • Fast onset
  • Short lived
  • Similar to Peptides

Includes Epinephrine, norepinephrine and dopamine

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

Direct Hormones

A

Secreted then act directly on the target tissue

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

Tropic Hormones

A

Require and intermediary to act

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

Testosterone

A
  • Source: Testes and Adrenal Cortex
  • Steroid Hormone
  • in response to Gonadotropins LH / FSH ; develops and maintains male reproductive system and secondary male characteristics like muscle growth, voice deepening and hair growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Estrogen

A
  • Source: Ovary and Placenta
  • Steroid Hormone
  • Develops and maintains female reproductive system in response to Gonadotropins and causes secondary female characteristics like hair / breast growth and fat distribution
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Progesterone

A
  • Source : Ovary and Placenta
  • Steroid Hormone
  • Promotes maintenance of the endometrium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Melatonin

A
  • Source: Pineal gland located deep within the brain
  • Peptide Hormone
  • Involved in circadian rhythms and promote feelings of sleepiness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Erythropoietin

A
  • Source: Kidney
  • Peptide Hormone
  • Stimulates bone marrow to produce erythrocytes (RBCs) in response to low O2 levels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Atrial Natriuretic Peptide (ANP)

A
  • Source: Heart (atrial)
  • Peptide Hormone
  • Helps regulate salt and water balance; promotes excretion of Na+ thereby increasing urine volume
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Thymosin

A
  • Source: Thymus (behind sternum)
  • Peptide Hormone
  • Stimulate T-Cell Development and differentiation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Hypothalamus

A

Bridge between the nervous system and endocrine system by regulating the pituitary gland through tropic hormones and is capable of having organism wide effects

  • Regulated by a negative feedback system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Hypophyseal Portal System

A

Blood vessel that directly connects the hypothalamus with the anterior pituitary and stimulates the release of other hormones

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

Follicle Stimulating Hormone (FSH)

A
  • Triggered by Hypothalamic release of Gonadotropin Releasing hormone (GnRH)
  • Source: Anterior Pituitary
  • Peptide / Tropic Hormone
  • Stimulates follicle maturation in females and spermatogenesis in males
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Luteinizing Hormone (LH)

A
  • Triggered by Hypothalamic release of Gonadotropin Releasing hormone (GnRH)
  • Source: Anterior Pituitary
  • Peptide/ Tropic Hormone
  • Stimulates ovulation in females and testosterone synthesis in males
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Gonadotropin Releasing hormone (GnRH)

A
  • Source: Hypothalamus

- Stimulates release of FSH and LH

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

Adrenocorticotropic Hormone (ACTH)

A
  • Triggered by Hypothalamic release of Corticotropin Releasing Hormone (CRF)
  • Source: Anterior Pituitary
  • Peptide / Tropic Hormone
  • Stimulate the adrenal cortex to synthesize and secrete glucocorticoids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Thyroid Stimulating Hormone (TSH)

A
  • Triggered by Hypothalamic release of Thyroid Releasing Hormone (TRH)
  • Source: Anterior Pituitary
  • Peptide /Tropic Hormone
  • Stimulates thyroid to produce thyroid products (hormones)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Corticotropin Releasing Hormone (CRF)
- Source: Hypothalamus | - Triggers release of Adrenocorticotropic Hormone (ACTH)
26
Thyroid Releasing Hormone (TRH)
- Source: Hypothalamus | - Triggers release of Thyroid Stimulating Hormone (TSH)
27
Prolactin
- Triggered by Hypothalamic release of Prolactin Inhibiting Factor (PIF) or Dopamine - Source: Anterior Pituitary - Peptide / Direct Hormone - Stimulates milk production in the mammary glands; Removal of Estrogen and Progesterone result in lactation
28
Endorphins
- Source: Anterior Pituitary - Peptide / Direct Hormone - Decrease pain perception / sensation and can promote Euphoria
29
Growth Hormone (GH)
- Triggered by Hypothalamic release of Growth Hormone Releasing Hormone (GHRH) - Source : Anterior Pituitary - Peptide /Direct Hormone - Stimulates bone / muscle growth; Prevents glucose re-uptake and stimulates breakdown of fatty acids increasing overall glucose level
30
Growth Hormone Releasing Hormone (GHRH)
- Source: Hypothalamus | - Triggers release of Growth Hormone (GH)
31
Prolactin Inhibiting Factor (PIF)
- Source: Hypothalamus | - Triggers release of Prolactin
32
Gigantism
Excess of Growth Hormone (GH) released before closure of epiphyseal plates
33
Dwarfism
Deficit of Growth Hormone (GH)
34
Acromegaly
Excess Growth Hormone in adults; enlarging smaller bones like those found in the hands, feet and head
35
Posterior Pituitary
Neurons are connected from the hypothalamus to the posterior pituitary ("Master Gland")
36
Antidiuretic Hormone (ADH) or Vasopressin
- Source: Hypothalamus - Released by : Posterior Pituitary - Peptide Hormone - Stimulates water reabsorption in kidneys by increasing permeability of collecting duct to water - Greater reabsorption from filtrate and greater retention of water increase blood volume and pressure
37
Oxytocin
- Source Hypothalamus - Released by : Posterior Pituitary - Stimulates uterine contractions during labor and smooth muscle contractions in breast to promote lactation - Involved in bonding behavior
38
Positive Feedback Loop
Identified by the theme of "spiraling forward" and have a definitive end point Ex: Contractions - oxytocin promotes stronger contractions and more of them ending in birth
39
Thyroid
Controlled by thyroid stimulating hormone which sets basal metabolic rate and calcium homeostasis
40
Triiodothyronine (T3)
Tyrosine with three iodine - Source: Thyroid Follicular Cells - Amino Acid Derivative Hormone - Stimulate metabolic activity
41
Thyroxine (T4)
Tyrosine with four iodine - Source: Thyroid Follicular Cells - Amino Acid Derivative Hormone - Stimulate metabolic activity
42
Calcitonin
- Source: Thyroid parafollicular cells (C-cells) - Peptide Hormone - Decrease blood [Ca2+]; Ca2+ is excreted from kidneys and increase Ca2+ storage in bones
43
Parathyroid Hormone (PTH)
- Source: Parathyroids - Peptide Hormone - Increase blood [Ca2+] and [Phosphate] by reducing reabsorption in kidneys and reabsorbing them from bone - Activates Vitamin D needed for absorption of Ca2+ and phosphate in the gut
44
Hypothyroidism
Deficiency of iodine or inflammation of thyroid in which thyroid hormones are insufficient or not secreted at all
45
Cretinism
Deficiency of thyroid hormone at birth (mental retardation and delay)
46
Hyperthyroidism
Excess of thyroid hormone
47
Parathyroid
4 small pea sized structures that sit on the posterior surface of the thyroid
48
Calcium
- Important in bone strength - Regulates muscle contraction - Cofactor allowing for clotting of blood - Role in cell movement, exocytosis and neurotransmitter release
49
Glucocorticoids
Cortisol + Cortisone - Source: Adrenal Cortex - CorticoSteroid Hormone - Increase [blood glucose] through gluconeogenesis - Decrease protein synthesis; anti-inflammatory - Decrease immunological Responses
50
Mineralocorticoids
Aldosterone - Source: Adrenal Cortex - CorticoSteroid Hormone - Increase water reabsorption in kidneys by increasing Na+ reabsorption - Promote K+ and H+ ion excretion
51
Cortical Sex Hormones
- Source: Adrenal Cortex - CorticoSteroid Hormone - Aids in producing androgens and estrogen
52
Epinephrine and Norepinephrine
- Source: Adrenal Medulla - Amino Acid Derivative Hormone - Secreted directly into circulatory system: Fight or Flight hormones in sympathetic nervous system - Increase blood [glucose] - Increase heart rate - Dilate Bronchi - Alter blood flow
53
Adrenal Medulla
On top of kidneys; consisting of Cortex and Medulla
54
Cortisol
Stress hormone; Increases blood sugar (ready source of fuel)
55
Pancrease
Both Exocrine and Endocrine Functions
56
Islets of Langerhans
Small groups of hormone producing cells - Alpha cells - Beta cells - Delta cels
57
Alpha Pancreatic Cells
Type of Islets of Langerhans Cells: | - Produce glucagon
58
Beta Pancreatic Cells
Type of Islets of Langerhans Cells: | - Produce Insulin
59
Delta Pancreatic Cells
Type of Islets of Langerhans Cells: | - Produce Somatostatin
60
Glucagon
- Source: Pancreas Alpha Cells - Peptide Hormone - Stimulates glycogen breakdown (glycogenolysis) - Increases blood [glucose] and stimulates degradation of fats and proteins - When fasting
61
Insulin
- Source: Pancreas Beta Cells - Peptide Hormone - Lowers blood [glucose] - Increases anabolic processes like protein and fat synthesis - When glucose is high
62
Somatostatin
- Source: Pancreas Delta Cells - Peptide Hormone - Suppresses secretion of glucagon, insulin and growth hormone (GH) - When there is high [glucose] and [amino acid]
63
Hypoglycemia
Excess insulin characterized by low blood [glucose]
64
Diabetes Mellitus
Underproduction, insufficient secretion or insensitivity to insulin
65
Hyperglycemia
Excess Glucose in blood (too little insulin)
66
Polyuria
Increase frequency of urination
67
Polydipsia
Increased thirst
68
Diabetes Mellitus Type 1
Autoimmune destruction of beta cells in pancreas; producing little to no insulin as a result
69
Diabetes Mellitus Type 2
Result of receptor-level resistance to the effects of insulin

Biology for the MCAT :) (10 decks)

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