Test 1

Question 1

Maternal Recognition of Sow

Answer 1

In the sow, maternal recognition of pregnancy begins 11-12 days into the cycle, with the signal being estradiol. Estradiol redirects PGF2a into the lumen of the uterus and away from the ovaries. If this did NOT happen, PGF2a would rich the ovaries and regress to the corpus luteum (which is vital to maintain pregnancy).

Question 2

In females, what stage of meiosis is arrested?

Answer 2

Diplotene of Prophase I

Question 3

Release of the mature spermatozoa into the lumen of the seminiferous tubule

Answer 3

Spermiation

Question 4

Sperm are made every ____ normally.

Answer 4

2 weeks

Question 5

Function of the mitochondrial sheath

Answer 5

-Cell that produces the energy

Question 6

ZP3 is…

Answer 6

-A receptor to sperm

Question 7

Luteal Regression of Ewe

Answer 7

PGF2a induces luteal regression and it is produced in the uterus. It reaches the ovary directly by way of the ovarian artery. Allows PGF2a to get directly to the CL. If PGF2a reaches the lungs it is unusable.

Question 8

How does P4 affect the endometrium and myometrium?

Answer 8

Endometrium: P4 increases secretions/ nourish embryo
Myometrium: P4 causes relaxation of muscles; allows stretching

Question 9

Lutenization

Answer 9

Opposite of Luteal regression. Induced by LH/FSH surge; follicular cells -> lute am cells; P4 is made (transformation of granulosa and theca cells)

Question 10

Before fertilization, the stage of meiosis that the oocyte is arrested in is….

Answer 10

Metaphase 2

Question 11

What hormone does CIDR release?

Answer 11

P4 to prevent ovulation

Question 12

Synchronization of 50 heifers

Answer 12

1. ) Want to control the ovary -> Corpus Luteum
2. ) Will place CIDR to act as the CL for 7 days (Uses P4 to prevent ovulation)
3. ) Then remove CIDR and give shot of PGF2a to kill any CL that were actually present (Should get 2/3 on the same cycle)
4. ) Give another shot of PGF2a 11 days later to kill any remaining CL present. (should get all on the same cycle)
5. ) Use GnRH 36 hours later to induce the LH surge and begin ovulation.

Question 13

Capacitation

Answer 13

Physiological changes that occur to sperm in the female reproductive tract (vagina). Has to occur in order for fertilization to take place. The physiological change is exposure of the egg-binding sites.

Question 14

Where does capacitation occur?

Answer 14

Vagina

Question 15

Total hysterectomy in ewe during the mid luteal phase of the estrous cycle, (a) how long is CL maintained and (b) why?

Answer 15

A) length of gestation (about 9 months)
B) Because the uterus is not able to produce and release hormones, like PGF2a, to control CL development or regression.
No negative feedback to stop the secretion of P4.

Question 16

Fertilization occurs in the uterus? T/F

Answer 16

False, oviduct

Question 17

FSH induces recruitment of a cohort of follicles? T/F

Answer 17

True

Question 18

What is the proteolytic enzyme released from acrosome of spermatozoa?

Answer 18

Acrosin –> helps break down acrosome

Question 19

What is Pampiniform Plexus?

Answer 19

Large system of veins that surrounds the testicular artery. Functions to regulate temperature in testes (cooler) and to allow high amounts of testosterone to be concentrated in the testes

Question 20

Explain Acrosin (Acrosomal Reaction)

Answer 20

When induced, the acrosome reaction allows sperm to pass through the acrosome and digest into the ZP of the oocyte for eventual DNA Dispersal.
The outer acrosomal membrane and plasma membrane fuse together and start to dissolve holes in the zona pellucid of the oocyte. The sperm then gets locked into the perivitella space of the oocyte.

Question 21

2 blocks to block polyspermy (induced by the cortical reaction

Answer 21

1) ZP Block- Prevents a second sperm from entering

2) Keeps the selected sperm from exiting

Question 22

Granulosa cells produce

Answer 22

Estradiol

Question 23

Theca Interna produce

Answer 23

Androstendione

Question 24

Are the cells of the 8-cell embryo considered totipotent and what does totipotent mean?

Answer 24

Yes, totipotent means they have the ability to make anything.
*Have all of the DNA required to make the whole animal

Question 25

What is meant by cleavage of the early embryo?

Answer 25

Mitotic division

Question 26

A primordial follicle contains a primary oocyte surrounded by the zona pellucida and a single layer of cuboidal granulosa cells? T/F

Answer 26

False.

No ZP at primary and pre-granulosa cells are flattened

Question 27

How did scientists determine that pre-antral follicular development was not dependent on gonadotropins?

Answer 27

• Removed the blood supply

- Gonadotropins to stop GnRH to reach -anterior pituitary, removed LH

Question 28

In a dominant follicle, the theca intern is steroidogenic and produces estridiol. T/F

Answer 28

• False
• Theca interna = androstendione
• Granulosa cells produce estradiol

Question 29

Steroid hormones are derived from _______

Answer 29

Cholesterol

Question 30

STAR is important for the

Answer 30

• Cholesterol to be converted to androstendione which is converted to estradiol by the granulosa cells.
• In the theca interna

Question 31

Name the hormone that induces regression of the corpus luteum and identify where it is produced

Answer 31

PGF2a secreted in the uterus

Question 32

What is the major component of cumulus cells?

Sperm head contains…

Answer 32

Hyaluronic acid

Sperm head: hyaluronidase