Exam 4- Male Reproductive Physiology II

Question 1

where is sperm stored?

Answer 1

tail of the epididymis

Question 2

what happens to sperm in the epididymis?

Answer 2

matures and gains ability to become motile

Question 3

what enters the epididymal duct?

Answer 3

sperm and rete fluid

Question 4

what produces the rhythmic contractions in the epididymis?

Answer 4

smooth muscle

Question 5

how can sperm end up in urine?

Answer 5

escapes out of tail of epididymis into ductus deferens to pelvic urethra

Question 6

where is sperm concentrated?

Answer 6

head of epididymis and continues throughout

Question 7

what do the functions in the epididymis depend on (with sperm)?

Answer 7

testosterone

Question 8

sperm must be both ___________________, yet _____________________

Answer 8

prepared to be motile
repressed from being motile

Question 9

what is necessary for sperm motility?

Answer 9

cyclic AMP

Question 10

what in the epididymis could help prevent motility?

Answer 10

lower calcium levels

Question 11

what is capacitation?

Answer 11

changes in sperm
can only truly occur in female system

Question 12

what happens in capacitation?

Answer 12

changes in plasma membrane that will allow fusion of sperm with oocyte and capacitation
change in position cytoplasmic droplet

Question 13

true/false: both frequent and infrequent ejaculation can affect sperm quality

Answer 13

true

Question 14

from which region of the epididymis are sperm ejaculated?

Answer 14

tail

Question 15

what happens when very frequent ejaculations occur?

Answer 15

sperm numbers reduced
immature sperm released

Question 16

what happens when there are very infrequent ejaculations?

Answer 16

quality of sperm generally poor

Question 17

what are the requirements for erection?

Answer 17

elevated arterial inflow
dilations of sinusoids in blood sinuses
restricted venous outflow
elevated intrapenile pressure
relaxation retractor penis muscle

Question 18

what is innervation doing in a non-erect penis?

Answer 18

sympathetic
vasoconstriction
smooth muscle tone within walls of blood sinuses

Question 19

what is innervation doing in an erect penis?

Answer 19

more parasympathetic than sympathetic
nonadrenergic, noncholinergic (NANC)
release nitric oxide
blood vessels/sinuses relax
engorgement

Question 20

what is required for an erection- emission?

Answer 20

sensory stimuli
hypothalamus
oxytocin
movement sperm

Question 21

what does oxytocin do during emission and what releases it?

Answer 21

posterior pituitary
smooth muscle contraction

Question 22

what do smooth muscle contractions do in emission?

Answer 22

in epididymis and ductus deferens
move sperm into ductus deferens and pelvic urethra: positioned for ejaculation

Question 23

what secretions help form the seminal plasma?

Answer 23

from accessory sexual glands
from tail of epididymis

Question 24

what is present in seminal plasma?

Answer 24

fructose
ovulation induction factor (OIF)
female immune tolerance substances
+/- copulation plug
fluid for volume (important in pig)

Question 25

does parasympathetic or sympathetic stimulation control ejaculation?

Answer 25

sympathetic

Question 26

what are muscle contractions in ejaculation initiated by?

Answer 26

sensory stimulation of glans (intromission) pudendal nerve transmits

Question 27

what are the target muscles in ejaculation?

Answer 27

urethralis ischiocavernosus bulbospongiosus

Question 28

where does phagocytosis of sperm occur?

Answer 28

vagina, cervix, uterus neutrophils enter uterus post-mating

Question 29

can phagocytosis of sperm in the female tract do damage?

Answer 29

yes- inflammatory response- to uterine endometrium

Question 30

what happens to "sequestered" sperm?

Answer 30

capacitation released gradually isthmus of oviduct viability promoted

Question 31

what is transport of sperm in the female tract under the influence of?

Answer 31

estradiol

Question 32

what is capacitation?

Answer 32

membrane of sperm changes so that acrosome reaction can take place motility pattern changes: hyper-activated motility: spiral trajectory

Question 33

what does the acrosome reaction enable the sperm to do?

Answer 33

penetrate the zona pellucida fuse with oocyte membrane

Question 34

can acrosomal damage be reveresed?

Answer 34

no

Question 35

what does the plasma membrane of the oocyte fuse with?

Answer 35

fusion proteins on equatorial segment of sperm

Question 36

what does alpha-fetoprotein do?

Answer 36

prevents most of estradiol from crossing blood-brain barrier in CNS

Question 37

what is testosterone converted into in the male fetal brain?

Answer 37

estradiol by aromatase

Question 38

what is desensitization?

Answer 38

when a cell is exposed to LH for too long and no longer responds

Question 39

is sperm concentrated in the rete of the testis?

Answer 39

no

Question 40

what is restricted venous outflow in an erect penis aided by?

Answer 40

smooth muscle contractions arterial engorgement

Question 41

what nerve stimulates the urethralis, ischiocavernosus, and bulbospongiosus muscles during ejaculation?

Answer 41

somatic nerve- pudendal

Question 42

in what species is the phagocytosis of sperm and the ensuing inflammatory response especially important?

Answer 42

horses

Question 43

what is the initiation of the acrosome reaction?

Answer 43

sperm binding with zona

Question 44

what does the acrosome reaction involve?

Answer 44

fusion of plasma membrane of sperm with outer acrosomal membrane of sperm creates vesicles/pores enzymes pass through pores

Question 45

where is sperm modified during the acrosome reaction?

Answer 45

equatorial segment

Question 46

what is acrosin?

Answer 46

an enzyme released from the acrosome reaction hydrolyzes zona proteins

Question 47

where are pheromones produced?

Answer 47

urine feces vaginal secretions saliva specific scent glands