Reproductive - week 22

Question 1

purpose of reproductive system

Answer 1

produce a cell (gamete) to combine with another cell (gamete) to create a new organism

done through the process of meiosis

Question 2

chromosomes

Answer 2

long strands of DNA
- contain genetic material
- how DNA is packaged
- maternal contribution: oocytes
- paternal contribution: sperm

Question 3

diploid

Answer 3

number of distinct chromosomes
in humans: 46 chromosomes (23 homologous pair)

Question 4

haploid

Answer 4

half the amount of chromosomes than diploid

23 in humans

Question 5

gametes

Answer 5

involved in fertilization
- haploid cells
- made in gonads of parent organism
- sperm made in testes
- oocytes made in ovaries

Question 6

germ line cells

Answer 6

give rise to gametes
- eventually become gametes through the process of meiosis
- found in testes or ovaries

Question 7

meiosis

Answer 7

process where diploid cell becomes a haploid gamete to be used in fertilization and create a new organism

Question 8

negative feedback loop

Answer 8

helps maintain hormonal balance by reducing secretion of GnRH and gonadotropins (LH and FSH)

prevents overproduction of gametes

Question 9

positive feedback loop

Answer 9

involves surge in LH triggered by rising estrogen - leads to ovulation and a mature egg

Question 10

bladder

Answer 10

stored urine – connected to ureter through a tube that runs through the prostate

Question 11

ureter

Answer 11

connects kidneys to bladder

Question 12

rectum

Answer 12

stored feces until expelled through anus during defacation

Question 13

seminal vessicle

Answer 13

contributes to large amounts of fluid to semen during ejaculation
- fluid is rich in fructose and enzymes
- helps nourish and maintain sperm

Question 14

prostate

Answer 14

gland secretes enzymes and fluid to neutralize acidic environment of urethra and vagina

• without this sperm would die
• growth and maintenance of prostate regulated by testosterone

Question 15

ejaculatory duct

Answer 15

drains into urethra

Question 16

bulbourethral gland

Answer 16

releases a neutralizing and lubricating fluid into ureter before ejaculation
- fluid is alkaline
- necessary to neutralize acidic environment of urethra that occurs after urination
- ejaculate and urine exits body via the same tube

Question 17

epididymis: site of sperm maturation and storage

Answer 17

site of sperm maturation and storage

Question 18

testes

Answer 18

site of sperm production - produce and secrete testosterone and inhibin

done in response to gonadotropins from anterior pituitary

Question 19

scrotum

Answer 19

fleshy sac that houses testes

Question 20

penis

Answer 20

consists of erectile tissue and acts as conduit for sperm transfer during copulation
- conduit for urine excretion

Question 21

urethra

Answer 21

conducts both urine and sperm to the penis and out of body

Question 22

vas Deferans

Answer 22

tube connecting testes to ureter that conducts sperm during ejaculation

Question 23

when does sperm production begin?

Answer 23

at puberty, when they start producing testosterone

Question 24

spermatogonia

Answer 24

germ cell
46 pairs of chromosomes
divides by mitosis into 2 cells: primary cell and another spermatogonia cell

Question 25

acrosome

Answer 25

on a mature sperm - specialized organelle - contains a lot of enzymes and allows sperm to penetrate the oocyte during fertilization

Question 26

testosterone production

Answer 26

- GnRH released from hypothalamus, stimulates anterior pituitary to release FSH and LH - FSH acts on Sertoli cells to promote spermatogenesis while also producing hormone: inhibin - inhibin feeds back on anterior pituitary to decrease FSH and LH production - LH stimulates Leydig cells - produces testosterone - testosterone feeds back to hypothalamus and anterior pituitary gland to decrease production of FSH and LH

Question 27

testosterone that is produced in adrenal glands

Answer 27

- plays a role in muscle formation, blood production - also produced in females - production involves complex rxns beginning with cholesterol and formation of many intermediate molecules

Question 28

andropause

Answer 28

menopause but in men. happens in adult age (around 40-50 yrs) testosterone production decreases

Question 29

testosterone function

Answer 29

1. development of male reproductive tract and external genitalia in developing a baby 2. growth and development of all male reproductive organs at puberty 3. development of male secondary sex characteristics at puberty (muscle growth, hair growth on face, genitalia, deeper voice) 4. sex drive at puberty 5. spermatogenesis 6. bone and skeletal muscle growth 7. increase aggression