Repro Physl 2

Question 1

What is Cholesterol the main synthesis for?

Answer 1

The sex hormones

Question 2

What does Aromatase do?

Answer 2

Converts progesterone to Estrone a type of estrogen

Question 3

What does Aromatase do?

Answer 3

Converts testosterone to Estradiol

Question 4

What does 5-alpha reductase do?

Answer 4

Converts testosterone to DHT which is more potent

Question 5

What kind of actions do the Androgens typically have?

Answer 5

Masculinizing actions

Question 6

What is an example of an androgen?

Answer 6

Testosterone

Question 7

What are the Androgens mostly synthesized by?

Answer 7

The testes

Question 8

Where does other androgen synthesis occur?

Answer 8

In the adrenal cortex

Question 9

What is the difference between adrenal source androgens and testes androgens?

Answer 9

Adrenal source androgens tend to be less potent than testosterone

Question 10

What is the issue with adrenal gland androgens?

Answer 10

They are not potent enough to maintain normal reproductive function

Question 11

Where are androgen produced in women?

Answer 11

In the adrenal glands

Question 12

Can androgens be produced in ovaries?

Answer 12

Yes but in small amounts

Question 13

What is DHT?

Answer 13

A more potent form of testosterone synthesized by 5-alpha-reductase

Question 14

Where are most estrogens produced in females?

Answer 14

The ovaries

Question 15

What is the prominent circulating form of estrogen in women of reproductive age?

Answer 15

Estradiol

Question 16

What is Estrone?

Answer 16

The prominent estrogen in post menopausal women

Question 17

What is Estriol?

Answer 17

The prominent estrogen found in pregnant women produced by the placenta

Question 18

What do estrogens require to become estrogens?

Answer 18

They need to be produced from androgens via aromatization

Question 19

What does Enzyme aromatase do?

Answer 19

Facilitates the transition from androgens to estrogens

Question 20

Where are estrogens in males released?

Answer 20

From the testes and in non-gonadal tissues like the brain, skeletal muscle, and adipose tissue

Question 21

Which tissues possess aromatase in males to convert androgens to estrogens?

Answer 21

Adipose tissue, brain, skeletal muscle

Question 22

What is Progesterone produced by?

Answer 22

The ovaries

Question 23

Which phase of the menstrual cycle is progesterone produced?

Answer 23

The luteal phase

Question 24

What is the precursor of progesterone in males?

Answer 24

Pregnenolone

Question 25

In addition to the ovaries, where can progesterone also be procued?

Answer 25

The adrenal glands

Question 26

What hormones does the placenta produced?

Answer 26

Estrogen and progesterone

Question 27

What is the solubility of gonadal hormones?

Answer 27

They are lipid soluble so they can diffuse easily into cells

Question 28

What do Gonadal steroid hormones do once they diffuse into a cell? (classical pathway)

Answer 28

They bind to the receptor and form a hormone-receptor complex which binds to DNA and modify mRNA formation leading to the modification of protein synthesis and alter circulating protein levels

Question 29

What are the characteristics of the non-genomic pathway of Gonadal Steroids?

Answer 29

* More rapid * Different receptor * In various tissues

Question 30

What are the Gonadal Steroid important for?

Answer 30

* Development of accessory reproductive organs | * Development of secondary sex characteristics

Question 31

What are the accessory reproductive organs?

Answer 31

* Duct system carrying sperm or eggs | * Breast development

Question 32

What are Secondary Sexual Characteristics?

Answer 32

* Phenotypic difference between males and females * Hair distribution * Body shape * Height

Question 33

What produces Gonadotropin-releasing hormone (GnRH)?

Answer 33

The Hypothalamus

Question 34

Where does GnRH go from the hypothalamus?

Answer 34

The hypothalamic-pituitary portal vessels to the anterior pituitary

Question 35

Which portion of the pituitary does GnRH act on?

Answer 35

The anterior pituitary

Question 36

What is the source of GnRH?

Answer 36

The neuroendocrine cells in the hypothalamus

Question 37

How does GnRH affect the anterior pituitary?

Answer 37

It stimulates the release of FSH and LH

Question 38

Where do FSH and LH go from the anterior pituitary?

Answer 38

They go into the circulation and act on the Gonads

Question 39

How do FSH and LH affect the gonads?

Answer 39

Facilitates the production of sex hormones and support gametogenesis

Question 40

Where does the stimulation of the production of sex hormones by FSH and LH act?

Answer 40

Anywhere in the body with estrogen and androgen receptors

Question 41

What has a negative feedback on GnRH?

Answer 41

The production of sex hormones and FSH and LH

Question 42

How do sex hormones affect FSH and LH release?

Answer 42

Testosterone has a negative feedback effect on the anterior pituitary. And estrogen can have either a positive or negative feedback effect

Question 43

How does impaired function of the hypothalamus or anterior pituitary affect gonadal steroids and gametogenesis?

Answer 43

It causes failure to secrete gonadal steroid and gametogenesis

Question 44

What does LH tend to act on and what does it do?

Answer 44

The endocrine cells of the gonads (ovaries or testes) and causes them to produces steroid and peptide hormones

Question 45

What does FSH tend to stimulate?

Answer 45

Gamete production

Question 46

What is the dual role of LH in females?

Answer 46

It plays a role in gamete production and stimulates endocrine cells to produces steroid and peptide hormones

Question 47

What happens if there is not enough LH?

Answer 47

Ovulation cannot happen

Question 48

Which levels of estrogen have negative feedback effects?

Answer 48

Low-moderate levels

Question 49

What kind of feedback do high levels of estrogen have?

Answer 49

It has a positive feedback effect

Question 50

What is the pattern of GnRH release?

Answer 50

It has pulsing release every 1-3 hrs

Question 51

What is the pulse of GnRH followed by?

Answer 51

A pulse in FSH and LH

Question 52

What is the GnRH pulse generator?

Answer 52

The region of the hypothalamus responsible for producing GnRH

Question 53

Why is GnRH released in pulses?

Answer 53

Because steady high levels down-regulates the receptors on gonadotropin cells in the pituitary

Question 54

How does a GnRH agonist affect cancer cells?

Answer 54

It slows the growth the cancer cells by down regulating the receptors

Question 55

Where do GnRH neurons receive input?

Answer 55

Other brain regions or circulating hormones

Question 56

What does kisspeptin do?

Answer 56

Controls the pulsatile pattern of the GnRH neurons

Question 57

What hormones are located upstream of GnRH neurons?

Answer 57

Kisspeptin neurons

Question 58

What is kisspeptin responsible for initiating?

Answer 58

Puberty

Question 59

What kind of feedback can things have on kisspeptin neurons?

Answer 59

sex hormones can have negative or positive feedback on kisspeptin neurons

Question 60

What is the regulation of LH and FSH release by sex hormones in addition to?

Answer 60

Inhibins

Question 61

Where are inhibins produced and what they do?

Answer 61

They are produced by the gonads and contribute to the control of gonadotropin release and FSH release from the anterior pituitary

Question 62

What is reproductive function in females affected by?

Answer 62

* Stress * Nutritional status * Daylight cycle * Environmental estrogens

Question 63

How does Melatonin affect GnRH production?

Answer 63

It tends to inhibit GnRH production

Question 64

Why are environmental estrogens bad?

Answer 64

Because they act in the body the same way that estrogens do and bind to estrogen receptors or they may be anti-estrogenic

Question 65

Where can environmental toxins accumulate?

Answer 65

In fat tissue