Exam 4 | Endocrine pt. 1

Question 1

What is the endocrine responsible for?

Answer 1

The endocrine system is responsible for maintaining homeostasis through the production and release of hormones, which are a specific type of signaling molecule/ chemical in vertebrates and invertebrates.

Question 2

What other body systems does the endocrine system work with?

Answer 2

the nervous system, digestive system, renal system and reproductive system. Nearly all autonomic/ physiological processes are under some degree of endocrine regulation.

Question 3

What are hormones?

Answer 3

hormones are a type of long-distance signaling molecule capable of either diffusing directly across the cell membrane, or binding to a receptor protein on the surface of a target cell, triggering an intracellular signaling cascade in response to the binding of the hormone

Question 4

What are the 2 types of hormones?

Answer 4

Central hormones and peripheral hormones

Question 5

What are central hormones?

Answer 5

Central Hormones are those produced by specialized neurons in the hypothalamus, and are thus produced within the central nervous system (CNS). These hormones are typically transported to either the posterior or anterior pituitary glands, where they are then stored and released.

Question 6

What are peripheral hormones?

Answer 6

Peripheral Hormones are those that are produced and secreted by cells in peripheral glands. The production and secretion of these hormones occurs in response to the detection of a central hormone

Question 7

What are the 3 chemical categories that hormones can be divided into?

Answer 7

Amine, Peptide (and protein), and steroid

Question 8

What are amine hormones?

Answer 8

Amine hormones are those that contain and amine group (nitrogen and hydrogen). They’re the smallest ones

Question 9

What is the polarity of an amine hormone?

Answer 9

They’re considered to be water soluble (polar); if small enough, can simply diffuse across the cell membrane of target cells.

Question 10

Give an example of an amine hormone.

Answer 10

They are often derived from amino acids, and common examples are norepinephrine (produced in the central nervous system) and epinephrine (produced in the adrenal cortex). These hormones are considered to be water solub

Question 11

What are peptide hormones?

Answer 11

Hormones derived fro amino acids and have at least a primary structure in their complexity; sometimes higher level of structures from secondary to quaternary; usually tertiary is the highest

Question 12

What is the polarity of a peptide hormone?

Answer 12

Considered to be water soluble (polar); n most cases, they are too large to diffuse directly across the cell membrane and thus require special receptor proteins on the target cell membrane to relay their signals.

Question 13

Give an example of a peptide hormone.

Answer 13

Examples of peptide/ protein hormones include oxytocin and Human Growth Hormone (HGH).

Question 14

What’s a steroid hormone?

Answer 14

Hormones that are derived from cholesterol and are considered to be lipids.

Question 15

What is the polarity of a steroid hormone?

Answer 15

They’re lipids so non polar; Thus, these hormones must signal via special receptor proteins on the membrane of target cells.

Question 16

Give an example of a steroid hormone.

Answer 16

Common examples of steroid hormones include the primary sex hormones, testosterone, estrogen and progesterone.

Question 17

Describe how intracellular signaling cascades work.

Answer 17

an external stimulus, a ligand, binds to a membrane-bound protein known as a receptor. Each receptor binds to a specific ligand, a behavior that is common across all major classes of proteins. The binding of the ligand to the receptor triggers a cascade of molecular changes within the cell. Ultimately, the “message” conveyed through this cascade results in a final “response” from the cell: in the vast majority of cases, this response is a change in gene expression, which leads to a subsequent change in protein expression.

Question 18

Give an example of an intracellular signaling cascade.

Answer 18

A more specific example of an intracellular signaling cascade is the G-protein Coupled Receptor (GPCR)-mediated cascade

Question 19

What are the 3 types of chemical messengers a hormone can be?

Answer 19

autocrine, paracrine, and endocrine

Question 20

What’s autocrine signaling?

Answer 20

When signaling occurs when a cell signals itself

Question 21

What’s paracrine signaling?

Answer 21

When signaling occurs when cells signal to nearby neighbors; typically takes place within a tissue or gland

Question 22

What’s endocrine signaling?

Answer 22

When signaling occurs when cells signal to far away targets through the use of blood vessels; the slowest; occurs between tissues/glands

Question 23

Why is autocrine signaling important?

Answer 23

To maintain homeostasis; used to regulate itself

Question 24

What’s neuroendocrine signaling?

Answer 24

This occurs when an individual neuron (or a group of neurons) communicates directly with non-neural cells in a gland (like the pituitary gland) to trigger downstream hormone production/signaling

Question 25

Why is neuroendocrine signaling important?

Answer 25

It’s essential for connecting the nervous system to the endocrine system particularly at the junction between the hypothalamus and anterior pituitary gland

Question 26

How does neuroendocrine signaling work?

Answer 26

The presynaptic cell (neuron) releases chemicals into the synapse that bind to their corresponding receptors on the postsynaptic cell (endocrine cell), causing a cascade of intracellular events in the endocrine cell.

Question 27

So where does neuroendocrine signaling take place?

Answer 27

At the hypothalamus-pituitary junction

Question 28

How are hormones secreted between the hypothalamus and pituitary gland?

Answer 28

The hypothalamus and posterior pituitary gland are directly connected, so the hormones produced in the hypothalamus are released directly to the posterior gland to be stored and released into blood stream

The hypothalamus and anterior pituitary gland are indirectly connected so neurons in the hypothalamus produce and secrete hormones into the portal vein system where they then travel to the anterior gland to trigger the production and release of stimulating hormones

Question 29

What is the hypothalamus?

Answer 29

It is considered to be the “command center for the endocrine system” & primary central hormones (releasing hormones) are produce and secreted here; neurons within the various hypothalamic nuclei are capable of producing hormones that target the pituitary glands to stimulate secondary central hormone release.

Question 30

What are the hormones produced in the hypothalamus?

Answer 30

1) Thyrotropin Releasing Hormone (TRH)
2) Gonadotropin Releasing Hormone (GnRH)
3) Corticotropin Releasing Hormone (CRH)
4) Oxytocin
5) Vasopressin (Antidiuretic Hormone, ADH)

Question 31

What does Thyrotropin Releasing Hormone (TRH) do?

Answer 31

It targets the anterior pituitary gland to trigger the production and release of Thyroid Stimulating Hormone (TSH).

Question 32

What does Gonadotropin Releasing Hormone (GnRH) do?

Answer 32

It targets the anterior pituitary gland to trigger the production and release of Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH).

Question 33

What does Corticotropin Releasing Hormone (CRH) do?

Answer 33

It targets the anterior pituitary gland to trigger the production and release of Adrenocorticotropic Hormone (ACTH).

Question 34

What does oxytocin do?

Answer 34

It is transported to and stored in the posterior pituitary gland.

Question 35

What does vasopressin (Antidiuretic hormone ADH) do?

Answer 35

It s transported to and stored in the posterior pituitary gland.

Question 36

What is the posterior pituitary gland (the Neurohypophysis)?

Answer 36

This gland is considered to be part of the central nervous system due to its direct connection to the hypothalamus.

Question 37

What function does the posterior pituitary gland serve?

Answer 37

The posterior pituitary gland is smaller than the anterior pituitary gland, and does not produce many hormones. Thus, it’s primary function is to store two hormones produced in the hypothalamus (oxytocin and vasopressin) and release them in response to ascending feedback from the peripheral glands (specifically, the uterus and kidneys, respectively).

Question 38

What is the anterior pituitary gland (the adenohypophysis)?

Answer 38

The anterior gland is not considered to be part of the CNS and is thus not comprised of neural tissue.

Question 39

What function does the anterior pituitary gland serve?

Answer 39

he anterior pituitary gland is the larger of the two divisions of the pituitary gland, and produces several hormones in response to the detection of hormones secreted from the hypothalamus.

Question 40

What hormones are produced in the anterior pituitary gland?

Answer 40

1) Thyroid stimulating hormone (TSH)
2) Adrenocorticotropic hormone (ACTH)
3) Follicle Stimulating hormone (FSH)
4) Luteinizing hormone (LH)
5) Growth Hormone (GH)
6) Prolactin (PRL)
7) Endorphins

Question 41

What does the thyroid stimulating hormone do?

Answer 41

It is produced and secreted in response to Thyrotropin Releasing Hormone (TRH); it targets the thyroid

Question 42

What does the adrenocorticotropic hormone do?

Answer 42

It is produced and secreted in response to Corticotropin Releasing Hormone (CRH); it targets the adrenal cortex

Question 43

What does the follicle stimulating hormone do?

Answer 43

It is produced and secreted in response to Gonadotropin Releasing Hormone (GnRH); it targets the testes and ovaries

Question 44

What does the luteinizing hormone do?

Answer 44

It is produced and secreted in response to Gonadotropin Releasing Hormone (GnRH); it targets the testes and ovaries

Question 45

What does the growth hormone do?

Answer 45

It follows a 24-hour (circadian) cycle in production and release; it targets the entire body

Question 46

What does the prolactin hormone do?

Answer 46

It targets the mammary glands (in mammals)

Question 47

What does the endorphin hormones do?

Answer 47

It targets pain receptors in the brain

Question 48

What are peripheral glands?

Answer 48

These are glands found outside of the brain which participate in various homeostatic mechanisms and physiological processes.

Question 49

List the peripheral glands

Answer 49

1) parathyroid glands
2) thyroid
3) adrenal glands
4) Gonads (testes found in biological males & ovaries found in biological females)

Question 50

Describe the parathyroid glands.

Answer 50

The parathyroid glands are small glands located behind the thyroid gland, and produce parathyroid hormone (PTH) which plays an essential role in regulating blood calcium and phosphorus levels.

Question 51

Describe the thyroid gland.

Answer 51

The thyroid gland is a butterfly-shaped structure located at the base of the throat, and is important for managing one’s metabolism and other vital autonomic functions.

Question 52

Describe the adrenal glands.

Answer 52

The adrenal glands sit on top of each kidney, and are the site of cortisol production. Thus, these glands play a critical role in the acute and chronic stress response.

Question 53

Describe the gonads.

Answer 53

The gonads (which include the testes in biological males, and the ovaries in biological females) are the primary sex organs, and are critical for reproduction and sexual behavior.