topic 13 powerpoint 13.0

Question 1

Steroids

Answer 1

-type of lipid
-membrane permeable
- refers to both naturally occurring hormones produced by the body and synthetic medications that mimic the effects of these hormones.

Question 2

Describe the structure of a steroid

Answer 2

-fused ring
-C-H nonpolar
-attached functional group

Question 3

What is an example of a fungus steroid?

Answer 3

ergosterols: same function as cholesterol in animals

Question 4

What are two plant steroids?

Answer 4

-phytosterol: structural component of cell membrane
-brassinosteroid: pollen tube formation, cell expansion and elongation, vascular differentiation

Question 5

What is an example of a vertebrae steroid?

Answer 5

cholesterol
-structural component involved in membrane permeability and fluidity
- amkes up bile acids, steroid hormoes, vitamin D
-carried in lipoprotein(HDl/LDL)

Question 6

Different between HDl and LDL

Answer 6

HDL high-density lipoprotein
-good” cholesterol because it helps remove excess cholesterol
LDL low-density lipoprotein.
- cholesterol from the liver to the cells in the body, including the cells lining the arteries.

Question 7

What conditions gives rise to atherosclerosis?

Answer 7

having high levels of LDL and low levels of HDL in the blood

Question 8

how does Cholesterol regulate membrane fluidity?

Answer 8

Cholesterol helps regulate membrane fluidity by preventing the fatty acid chains of phospholipids in the cell membrane from packing too closely together.

Question 9

sterone

Answer 9

steroid acts as a hormone
steroid hormone
-corticosteroid and sex steroid

Question 10

How do sterones regulate hormone secretion?

Answer 10

can regulate hormone secretion by binding to receptors that can activate pathway that can release hormones by endocrine glands and can inhibit hormone secretion

Question 11

How are sterones identified?

Answer 11

by the receptor the bind to. 5 types of receptors
1. Glucocorticoids (corticosteroid)
2.Mineralocorticoids (corticosteroid)
3.Androgens (sex steroid)
4.Estrogens (sex steroid)
5.Progestins (sex steroid)

Question 12

What is a sex steroid?

Answer 12

subset of sex hormones that produce sex differences or support reproduction

Question 13

What are androgens, estrogen, progestins?

Answer 13

-androgens: hormones key in development of male traits, ex: testerone[male organs]
-estrogen: hormones key in development of female traits, ex: estradiol[female organs]
-progestins: hormones that are primarily involved in the regulation of the menstrual cycle and pregnancy.

Question 14

What are corticosteroid?

Answer 14

type of steroid hormone synthesized from cholesterol in the adrenal cortex

Question 15

What type of hormone involved in regulating stress hormone and can reduce immune responses?

Answer 15

Glucocorticoids: subset of corticosteroid aka type of steroid hormone
-role in metabolism and immune function

Question 16

What type of hormone involved with the kidneys?

Answer 16

Mineralocorticoids: subset of corticosteroid aka type of steroid hormone
-maintain blood volume and control electrolytes and water levels by promoting sodium retention in the kidneys

Question 17

What is a hormone that doesn’t regulate hormone secretion?
hint: body builder

How do they perform their function?

Answer 17

Anabolic steroid
Interact with androgen receptors to increase mass and bone synthesis
-natural and synthetic
-increase production of actin and myosin proteins
-blocks the effect of the stress hormone cortisol
-favor cellular differentiation into muscle cells

Question 18

endocrine system

Answer 18

is a collection of glands that secrete hormones into the bloodstream to hit target receptor on organ.

Question 19

What is the synthetic version of HGH?

Answer 19

HGH: human growth hormone=somatotropin

Question 20

What is LH?

Answer 20

luteinizing hormone-stimulates ovulation

Question 21

Difference between ADH and aldosterone?

Answer 21

ADH=antidiuretic hormone, produced by hypothalamus and released by pituitary gland, acts on kidney to increase water absorption

Aldosterone: produced by adrenal glands and acts on kidneys to promote reabsorption of sodium and excretion of potassium

Question 22

T/F sweat glands are part of endocrine system

Answer 22

false: Exocrine glands (not part of the endocrine system) secrete products that are usually passed outside the body
(sweat glands, salivary glands). Also, the pancreas has exocrine cells.

Question 23

What is a tropic hormone?

Answer 23

a hormone that regulates hormone secretion by another endocrine gland

Question 24

What are the 4 major cell signaling in in the endocrine system?

Answer 24

1. classical endocrine signaling: secrete hormones over a distance
2. neuroendocrine signaling: neurosecretory neurons release neurohormones into the circulatory system
   3.paracrine regulation: cells release local regulators that diffuse through extracellular fluid to regulate nearby cells
   4.autocrine regulation: local regulators bind to same cells that produce it

Question 25

What are the 4 molecular classes of hormones?

Answer 25

1. Amine
2. peptide
   3.steroids
3. fatty acid

Question 26

What type of hormones fall under the molecular class called amine?

Answer 26

epinephrine and norepinephrine
-made from tyrosine

Question 27

What type of hormones fall under the molecular class called peptide?

Answer 27

PYY suppress appetite
made of amino acid chain

Question 28

What type of hormones fall under the molecular class called steroid?

Answer 28

aldosterone, cortisol, sex hormone
made from cholesterol

Question 29

What type of hormones fall under the molecular class called fatty acid?

Answer 29

prostaglandins
-paracrine and autocrine mediators
-bind to G-Protein-couple receptors
-produced by oxidation of cyclooxygenases[COX1/COX2]

Question 30

What are the effects of prostaglandins?

Answer 30

-EFFECTS: dilation/constriction of vascular smooth muscle cells, aggregation of platelets, pain sensitivity, decreased eye pressure, calcium movement, cell growth, and inflammation

Question 31

endocrine system has feed back systems
explain the one using GnRH hormone

Answer 31

NEGATIVE FEEDBACK

1.hypothalamus releases Gonadotropin-releasing hormone (GnRH) [tropin hormone], travels to the pituitary gland
A. releases LH[lutenizing hormone] and travels to the testes and binds to specific receptors on the Leydig cells. Increase in the production of testosterone.
B. releases FSH, brings to Sertoli cells in seminiferous tubules of testes, helps spermatogenesis and inhibin; inhibin negative feedback on anterior pituitary

Question 32

endocrine system has feed back systems
explain the one involving thyroid

Answer 32

1. [+ feed back]hypothalamus releases TRH[thyroid-releasing hormone] to pituitary
2. [+ feedback]releases TSH[thyroid stimulating hormone] to thyroid
3. The thyroid releases hormones that has negative feedback on pituitary

Question 33

In our body, do we expect to find hormones in low or high concentrations?

Answer 33

low because of amplification because binding of a hormone to receptors activates many proteins

Question 34

plasma membrane structure

Answer 34

plasma membrane is hydrophobic. It is composed of a phospholipid bilayer, which consists of hydrophilic heads facing the extracellular and intracellular environments, and hydrophobic tails facing each other in the middle of the membrane.

Question 35

Explain difference between hydrophobic and hydrophilic hormones?

Answer 35

hydrophilic hormones bind to surface receptors activating second messenger pathways
hydrophobic hormones bind inside cell activating/inhibiting regulatory proteins

Question 36

How can we differentiate aldosterone and epinephrine?

Answer 36

hydrophilic hormone: epinephrine
hydrophobic hormone: aldosterone

Answer 37

1) low sodium levels cause adrenal glands to secrete aldosterone
2) enters kidney cells and combines with aldosterone receptor activating it
3) active hormone receptor complex enters the nucleus and starts to transcript aldosterone-induced protein
4)aldosterone-induced protein is synthesized in the cytoplasm and act as a sodium channel allowing Na+ to enter and helps retain it