Reproductive Physiology of the Male & Fertilization

Question 1

Testosterone is made in the ______

Answer 1

LH cell

Question 2

The formation of spermatozoa in the seminiferous epithelium starts near the _____

Answer 2

basement membrane

Question 3

The spermatogonium divide to form other spermatogonia and ultimately _______

Answer 3

primary spermatocytes

Question 4

The primary spermatocytes are moved from the basal compartment through the tight junctions from adjacent Sertoli cells into the adluminal compartment where they eventually divide to form ________ and _________.

Answer 4

spermatocytes
spherical spermatids

Question 5

Where is testosterone converted to estradiol?

Answer 5

sertoli cells

Question 6

Define spermatogenesis

Answer 6

process of producing spermatozoa in the seminiferous tubules

Question 7

List the benefits of spermatogenesis

Answer 7

provides a continual supply of male gametes
provides genetic diversity
provides billions of sperm each day
provides an immunologically privileged site (Blood Testes Barrier)

Question 8

T/F: Developing germ cells are not destroyed by the male’s immune system

Answer 8

TRUE

Question 9

What are the three phases to spermatogenesis?

Answer 9

proliferation
meiotic phase
differentiation phase = spermiogenesis

Question 10

Define profliferation

Answer 10

mitotic divisions

Question 11

Define meiotic phase

Answer 11

involves primary and secondary spermatocytes
phase in which genetic diversity is guaranteed by DNA replication and crossing over

Question 12

Define differentiation phase

Answer 12

no further cell divisions
marked by transformation from spermatid to spermatozoa
- from spherical shaped to having head, midpiece, and flagellum

Question 13

Meiosis and differentiation take place in the ________ compartment.

Answer 13

adluminal

Question 14

1 spermatogonia divide into ______ spermatids

Answer 14

256 (some degenerate during the process)

Question 15

Each generation of cells is attached by ________. Thus, each generation divides synchronously in cohorts.

Answer 15

intracellular cytoplasmic bridges

Question 16

List the 4 phases in the differentiation phase

Answer 16

Golgi phase
cap phase
acrosomal phase
maturation phase

Question 17

Define Golgi phase

Answer 17

acrosomic vesicle formation
a newly formed, spherical spermatid has a well developed golgi apparatus.
the Golgi vesicles fuse creating pro-acrosomic granules.
the vesicle fusion continues until a large acrosomic vesicle is formed.
- 1st part differentiation phase

Question 18

Define cap phase

Answer 18

acrosomic vesicle spreading over the nucleus
the Golgi is migrating and the acrosome is forming a distinct cap
- 2nd part of differentiation phase

Question 19

Define acrosomal phase

Answer 19

nuclear and cytoplasmic elongation
the nucleus is beginning to elongate and the neck between the head and tail is forming
- 3rd part of differentiation phase

Question 20

Define maturation phase

Answer 20

final assembly that forms a spermatozoon
mitochondria form a spiral assembly around the flagellum that defines the midpiece
- 4th part of differentiation phase

Question 21

Define parts of the sperm

Answer 21

Capitulum – fits into a depression in the posterior nucleus
Middle piece – gives the tail the flexibility when it becomes motile
Principal piece – makes up a majority of the tail
Terminal piece – end piece – where only the microtubules end

Question 22

Sperm posses a _______, which beats in a snake-like fashion to propel the sperm forward

Answer 22

flagella
NOT cilia

Question 23

What is spermiation?

Answer 23

release of spermatozoa into seminiferous tubules

Question 24

Spermatozoa are [continually released / released in spurts] into the lumen of the seminiferous tubule

Answer 24

continuously released

Question 25

T/F: If you travel down the seminiferous tubule, you would see spermatozoa in different stages of development

Answer 25

TRUE

Question 26

What is the cycle of seminiferous epithelium?

Answer 26

the time it takes for progression through all stages * the time frame differs between species

Question 27

Spermatogenic waves move in ________, like a corkscrew, towards the inner part of the _______. They are able to do this because they have ________ which allow communication between the developing cells.

Answer 27

spirals
lumen
gap junctions

Question 28

For fertilization to occur, sperm and oocyte must meet up at a time when both are _______.

Answer 28

viable

Question 29

What are factors in determining when the right time is for fertilization?

Answer 29

behavior (estrus)
sperm factors (viability)
oocyte factors (viability)

Question 30

For the bull, buck, ram, dog, and cat, the sperm is deposited into the ______, which means it has to go through the ______ to the cervix

Answer 30

vagina
cervix

Question 31

Define immediate transport in the fertilization process

Answer 31

retrograde loss
phagocytosis
entrance into cervix/uterus
- 1st part

Question 32

Trace the pathway of fertilization

Answer 32

immediate transport (entrance into cervix/uterus)
cervix
uterus
oviduct
fertilization

Question 33

Where are the “privileged pathways”?

Answer 33

cervix

Question 34

During estrus, secretion of sulfomucins from the apical portion of the cervical mucosa produces ______

Answer 34

sheets of viscous mucus

Question 35

What are the phases of sperm transport in the female tract

Answer 35

rapid phase
sustained phase

Question 36

Define rapid phase

Answer 36

oviduct in minutes
await arrival of oocytes
+/- viable
result of muscle contraction

Question 37

Define sustained phase

Answer 37

sperm delivered to oviducts “continually” from reservoirs
* Cervix
* Uterotubal Junction (UTJ)
extends time over which fertilization can occur
selected so that they are viable and morphologically normal

Question 38

Stored sperm have [increased/decreased] binding ability

Answer 38

decreased

Question 39

T/F: All subfertile spermatozoa attach well

Answer 39

FALSE - only some

Question 40

Where is the spermatozoal reservoir?

Answer 40

oviductal isthmus

Question 41

T/F: The estrus cycle probably regulates the number and motility of spermatozoa attached

Answer 41

TRUE

Question 42

What are the barriers to fertilization?