Lecture 5 (endocrine system)

Question 1

Hormones

Answer 1

chemical messengers that travel through the blood stream

Question 2

types of hormones (three types:)

Answer 2

1.) Peptide Hormones = chains of amino acids (ex. endorphins)

2.) Amine Hormones = small molecules derived from a single amino acid (ex. seretonin)

3.) Steroid Hormones = lipid soluble hormones derived from cholesterol (ex. testosterone)

Question 3

chains of amino acids (ex. endorphins)

Answer 3

peptide hormones

Question 4

small molecules derived from a single amino acid (ex. seretonin)

Answer 4

amine hormones

Question 5

lipid soluble hormones derived from cholesterol (ex. testosterone)

Answer 5

steroid hormones

Question 6

Hormone receptors (two types:)

Answer 6

1.) Metabotropic receptors (GCPR’s)
*peptide and amine hormones

2.) Intracelluar nuclear receptors
*steroid hormones
*bind to receptor, active transport/pass through lipid membrane to the cell nucleus

Question 7

Intracelluar nuclear receptors

Answer 7

used by steroid hormones
they bind to receptor, pass through due to being lipid soluble (via transporters) go to nucleus

Question 8

what regulates hormones?

Answer 8

Negative feedback = brain monsters internal and external cues

*output of horses feedbacks to inhibit more output

Question 9

Neuroendocrine cells

Answer 9

receive synaptic input and fire action potentials = when they do hormones are released into the bloodstream

Question 10

posterior pituitary gland releases:

Answer 10

releases:
1.) oxytocin = promotes partition (mother infant bond, tribal bonds ect.)

2.) Vasopressin = regulates fluid balance (water/thirst regulation)

Question 11

where are oxytocin and vasspressin made?

Answer 11

the supraoptic and paraventricular nuclei (hypothalamic regions)

Question 12

what hormone does the anterior pituitary gland make?

Answer 12

tropic hormones = act on glands (such as gonads)

Question 13

how does the anterior pituitary gland release hormones?

Answer 13

1.) neuroendocrine cells synthesize releasing hormones

2.) release hormones travel along the hypothalamic-pituitary portal system —– govern the release of hormone

3.) releasing hormone travels to anterior pituitary via portal veins

4.) cells in the anterior pituitary respond via releasing tropic hormone into the bloodstream

Question 14

where are neuroendocrine cells ( which are responsible for secreting hormone into the bloodstream)

Answer 14

In the hypothalamic-pituitary portal system

Question 15

type of releasing hormone (stimulates FSH and/or LH):

Answer 15

Gonadotropin-releasing hormone (GnRH)
* stimulate follicle-stimulating hormone (FRH)
and / or
* stimulate luteinizing hormone (LH)

Question 16

In females = growth and maturation of eggs / secretion of estrogen from follicles

in males = sperm production

Answer 16

follicle - stimulating hormone (FSH)

made by neuroendocrine cels (a releasing hormone)

Question 17

In females = stimulates follicles to rupture releasing eggs. which form the corpus luteum —which secretes progesterone

in males = produces testosterone

Answer 17

luteinizing-hormone (LH)
Leydig cells

made by neuroendocrine cells (a releasing hormone)

Question 18

Luteinizing-hormone (LH)

Answer 18

In females = stimulates follicles to rupture releasing eggs. which form the corpus luteum —which secretes progesterone

in males = produces testosterone

Question 19

follicle - stimulating hormone (FSH)

Answer 19

In females = growth and maturation of eggs / secretion of estrogen from follicles

in males = sperm production

Question 20

Leydig cells

Answer 20

produce and secrete testosterone via LH

Question 21

what do the ovaries produce (two things):

Answer 21

eggs (ova)

sex steroids

Question 22

Two main types of sex steroids (females)

Answer 22

progestins = “to bear” helps maintain pregnancy
main steroid is progesterone

Estrogen = “frenzy” periodic cycle, receptivity
**main steroid is estradiol”

Question 23

Ovulatory cycle (4 main steps:)

Answer 23

1.) Follicle-stimulating hormone stimulates follicles to grow secreting estrogen

2.) estrogen stimulates hypothalamus and pituitary to release luteinizing hormone which triggers the follicles to rupture releasing eggs. develop into corpus luteum.

3.) corpus luteum secretes progesterone which helps maintain uterus for pregnancy

4.) in no pregnancy then cycle begins again….

Question 24

organizational/
activation hypothesis

Answer 24

differential exposure to hormones (in early development) influence the neural organization/circuit and underlying sexual behaviour

Question 25

organizational effects

Answer 25

permanent changes that occur in the brain

Question 26

activating effects

Answer 26

transient changes that occur to the brain