Chapter 16-Endocrine System

Question 1

Mechanisms for Intercellular Communication

Answer 1

Direct communication 
Paracrine Communication 
Autocrine communication 
Endocrine communication 
Sympathetic communication

Question 2

Explain direct communication

Answer 2

Transmitted through gap junctions
Chemical signals are ions, lipid-soluble
Distributed to adjacent cells via connexons

Question 3

Explain paracrine communication

Answer 3

Transmitted via extra cellular fluid
Chemical signal are paracrines
Limited to local area and cells with proper receptors

Question 4

Explain autocrine communication

Answer 4

Transmitted via extra cellular fluid
Chemical signals are autocrines
Distributed to the cell that actually secretes the chemical signal

Question 5

Explain endocrine communication

Answer 5

Transmitted via bloodstream
Chemical signal : hormones
Distributed to target cells with proper receptors

Question 6

Explain sympathetic communication

Answer 6

Transmitted via neurotransmitters across synapses

Distributed to very specific area with proper receptors.

Question 7

How are the endocrine and nervous systems similar?

Answer 7

Both release chemicals to bind to receptors on target cells.

They share common chemical messengers (like E and NE)

Both mainly use negative feedback

Both want to preserve homeostasis by regulating activities of other cells organs tissues and systems

Question 8

What are the three chemical structures of hormones?

Answer 8

Acid derivatives
Peptide hormones
Lipid derivatives

Question 9

What group of hormones are considered acid derivatives? Give an example of each.

Answer 9

Thyroid hormones (T4)
Catecholamines (E)
Tryptophan derivatives (Melatonin)

Question 10

Explain peptide hormones

Answer 10

Synthesized as prohormones

Short polypeptide chains of amino acids (like ADH) to small peptones like insulin.

Question 11

What is a pro hormone

Answer 11

Inactive precursor molecules that are converted to active hormones

Question 12

What organs or glands secrete polypeptide hormones?

Answer 12

Hypothalamus
Thymus
Heart
Digestive Tract
Pancreas 
Pituitary Glans

Question 13

Glycoproteins are considered peptide hormones. Describe them and give examples.

Answer 13

They are polypeptides with carb side chains that function as hormones.

Examples: TSH, LH, FSH

Question 14

Explain lipid derivatives

Answer 14

Carbon rings and side chains built either from eicosanoids (fatty acids) or cholesterol (sterilize hormones

Question 15

Eicosanoids

Answer 15

Paracrines that coordinate cellular activities and affect Enzymatic processes

Question 16

Leukotriens

Answer 16

An eicosanoid that has a secondary role as a hormone

Question 17

Prostaglandins

Answer 17

A second group of eicosanoids involved in coordinating local cellular activities. (Proglandin E)

Question 18

What organs release Steroid Hormones?

Answer 18

Reproductive organs
Cortex of adrenal glands
Kidneys

Question 19

What steroid hormone do reproductive organs release?

Answer 19

Androgens (male)

Estrogen and progesterone (female)

Question 20

What steroid hormone does the cortex of the adrenal gland release?

Answer 20

Corticosteroids

Question 21

What steroid does the kidneys release?

Answer 21

Calcitriol

Question 22

Why do steroids remain in circulation longer than secreted peptide hormones?

Answer 22

Because steroids are bound to specific transport proteins in blood.

Question 23

What is the endocrine system

Answer 23

Organs whose primary function is the production of hormones or paracrines

Question 24

What are the primary organs in the endocrine system?

Answer 24

Hypothalamus 
Pituitary gland
Thyroid gland
Parathyroid 
Adrenal gland
Pancreas 
Pineal gland

Question 25

Purpose of hypothalamus

Answer 25

“Control center” Fluid Balance Muscle contraction Controls hormone secretion of anterior lobe pituitary gland

Question 26

What hormones are produced in hypothalamus?

Answer 26

Antidiuretic (ADH) Oxytocin (OXT) Regularities Hormones

Question 27

What pituitary lobe does ADH and OXT travel to from hypothalamus?

Answer 27

Posterior lobe

Question 28

What pituitary lobe does regulatory hormones From hypothalamus travel?

Answer 28

Anterior lobe

Question 29

What are fenestrated capillaries?

Answer 29

Vessles that allow relatively large molecules to enter or leave the blood stream.

Question 30

Hypophyseal Portal System

Answer 30

Portal system from hypothalamus to pituitary gland.

Question 31

How do regulating hormones get from hypothalamus to pituitary gland arteriorlobe.

Answer 31

Via hypophyseal portals

Question 32

What are two classes of regulatory hormones?

Answer 32

``` Releasing Hormones(RH) Inhibiting hormones (IH) ```

Question 33

What are releasing hormones

Answer 33

Hormones that stimulate synthesis and secretion or one or more hormones in the anterior lobe

Question 34

What are inhibiting hormones?

Answer 34

Prevents synthesis and secretion of hormones from the anterior lobe.

Question 35

Purpose and functions of the pituitary gland

Answer 35

Direct chemicals from hypothalamus to other glands thereby regulating exocrine activities of glands.

Question 36

What are the two lobes of the pituitary gland?

Answer 36

The anterior and posterior lobe

Question 37

How many tropic hormones does the anterior lobe produce

Answer 37

7

Question 38

How many hormones does the anterior lobe produce

Answer 38

2

Question 39

What are tropic hormones?

Answer 39

Hormones that “turn on” endocrine glands or support the function of other organs

Question 40

What is another name for the pituitary gland ?

Answer 40

Hypophysis

Question 41

Where is the pituitary gland located?

Answer 41

Within the shell turcica (a small depression in the sphenoid bone)

Question 42

What is another name for the anterior lobe of the pituitary gland?

Answer 42

Adenohypophysis

Question 43

What kind of cells do the anterior lobe of the pituitary gland contain?

Answer 43

Endocrine cells

Question 44

What’s another name for the posterior lobe of the pituitary gland?

Answer 44

Neurophypophysis

Question 45

What kind of cells does the posterior of the pituitary contain?

Answer 45

Axons of hypothalamic neurons

Question 46

What hormones are produced in the anterior lobe of the pituitary gland?

Answer 46

``` TSH (thyroid stimulating hormone) PRL (prolactin) FHS (follicle stimulating hormone) LH (Luteinizing hormone) ACTH (adrenocorticotropic hormone) GH (growth hormone) MSH (melanocyte-stimulating hormone) ```

Question 47

What hormones are in the posterior lobe of the pituitary gland?

Answer 47

ADH | OXT

Question 48

What does TSH (thyroid Stimulating hormone) target?

Answer 48

Thyroid gland to trigger release of thyroid hormones.

Question 49

How is TSH released?

Answer 49

It is released in response to thyrotropin-releasing hormone (TRH) coming from hypothalamus.

Question 50

What cells does ACTH target?

Answer 50

The cells in the cortex or the adrenal glands

Question 51

What does ACTH do?

Answer 51

Simulate release of steroid hormones by adrenal cortex

Question 52

How is ACTH released?

Answer 52

From corticotropin-releasing hormone (CRH) from hypothalamus

Question 53

What are gonadotropins?

Answer 53

Hormones that regulate the activity of gonads.

Question 54

What are the two gonadotropins?

Answer 54

FSH (follicle stimulating hormone) | LH (luteinizing hormone)

Question 55

What is the purpose of FHS

Answer 55

Promotes ovary follicle development Works with LH stimulate secretion of estrogen. Promotes maturation of sperm.

Question 56

What is the purpose of LH (luteinizing hormone)?

Answer 56

Induces ovulation Promotes secretion of estrogens and pro estrogens Promotes secretion of androgens (like testosterone)

Question 57

What is the purpose of PRL (prolactin)?

Answer 57

Stimulate mammary gland development | Stimulates milk production

Question 58

What is the purpose of MHS (melanocyte stimulating hormone?

Answer 58

Produce melanin