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Mammalian Reproduction > Final Exam > Flashcards

Final Exam Flashcards

1
Q

True/False: if the testes of a ram are pushed into the body cavity at birth, and the scrotum is removed to prevent the testes from leaving the body cavity, the ram will be fertile, but have no sex drive when exposed to females in estrus

A

F

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2
Q

True or False: Elephants have paired mammary glands on the thoracic regions on the mammary ridges

A

True

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3
Q

FSH

Class?

Where is it synthesized?

Target tissue?

A
  1. glycoproteins
  2. anterior pituitary
  3. sertoli cell of testes
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4
Q

estradiol

Class?

Where is it synthesized?

Target tissue?

A
  1. steroid
  2. endometrium
  3. male- brain, inhibits long bone growth
  4. female- hypothalamus, entire repro tract and mammary gland
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5
Q

Manchette

A

forms the postnuclear cap

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6
Q

reduces uterine motility and allows implantation

What steroid hormone induces this change?

A

progesterone

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7
Q

True/False: After menopause, FSH and LH increased markedly in the blood of women due to a lack of negative feedback of estrogen on GnRH secreting neurons in the tonic release center of the hypothalamus

A

True

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8
Q

if a sheep and goat blastocyst are collected from donor females, and their inner cell masses are switched and the sheep and goat blastocysts were replaced in the same uteri from which they were collected

A

the sheep would give birth to a kid and the lamb would give birth to a sheep

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9
Q

female which requires the greatest area of association between the placental and the uterine wall per unit weight fetus for nutrient uptake from the mother

A

mare

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10
Q

True/False: prepubertal gilts housed in larger groups exhibit puberty at older ages than prepubertal gilts housed in small groups

A

F

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11
Q

Will the removal of the uterus affect the luteal lifespan in a: human?

A

removal of the uterus will not affect the lifespan of the CL

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12
Q

bulbospongiosus muscle

A

pushes semen from the pelvic urethra through the penile urethra

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13
Q

True/False: The endometrium of the ewe and cow have a small non glandular areas that protrude from the surface called caruncles which in pregnancy form the maternal portion of the placenta, while the endometrium of the sow and mare have many endometrial folds which increase the surface are for placental attachment

A

T

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14
Q

Testosterone

what phase describes this hormone in the male?

A

Natural male hormone that exerts a negative feedback on GnRH secretion from the tonic release center of the hypothalamus

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15
Q

golgi saccules

A

forms the proacrosomal granules

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16
Q

lining the ampulla of oviduct to mature and move oocyte to site of fertilization

A

secretory and ciliated columnar

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17
Q

females whose young do not have an absolute requirement for colostrum if they are to survive

A

woman

dog

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18
Q

women

signal that maintains luteal function in specie during maternal recognition of preg.

CL indep. or dep.

A

hCG

CL independent specie

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19
Q

True/False: the principle piece of the sperm cell conains the mitochondrial helix, which is a dense collection of mitochndria arranged spirally. This localization allows for mass ATP production, which is necessary for sperm motility.

A

False

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20
Q

female that is an induced ovulator

A
  • cat
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21
Q

True/False: In almost all species studied including humans, there is a marked increase in physical activity around the time of ovulation

A

True

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22
Q

True/False: phenotypic sex is how masculine or feminine an individual looks and is due to somatic characteristics determined by multiple genes located on its chromosomes

A

T

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23
Q

lining the vagina and covering the glans penis for protection

A

stratified squamous

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24
Q

specie in which PGF2a has no effect on luteal function

A
  1. dog
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25
Q

True/False: the ruminant, pig and mare have bicornuate uteri, while humans have simplex uteri, however all these species have only a single cervix

A

T

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26
Q

specie in which PGF2a receptors do not appear on luteal cells until day 14-16 when the CL is already dying thus exogenous PGF2a is ineffective in shortening CL lifespan

A
  1. pig
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27
Q

regu-mate is a progesterone that was developed as a estrous synchronizing agent in these 2 species

A
  1. mare
  2. pig
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28
Q

True/False: If a menstrual cycle is prolonged, the segment of the cycle which is increased in the length is the luteal phase.

A

False

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29
Q

Will the removal of the uterus affect the luteal lifespan in a: sheep?

A

removal of the uterus will prolong the lifespan of the CL

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30
Q

woman

placental type

number of tissue layers separating fetal and maternal blood stream

placental shape

A

hemochorial placenta

three layers

discoid shaped

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31
Q

Amnion

A
  • a high pressure bubble which surrounds the embryo to prevent it from being crushed by uterine contractions
  • somatic mesoderm + trophectoderm
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32
Q

At the end of lactational anestrus in the cow or season anestrus in the sheep, why is the development of a luteal nest required before ovulation and first estrus can occur?

A
  • a luteal nest is an unovulated luteinized follicle, which is the first source of progesterone
  • With that in mind, cows or sheep may have postpartum estrus, but without progesterone prior to the estrus cycle, it will result in a silent ovulation
  • the presence of the luteal nest allows for progesterone to “prime” the brain to be sensitive to estradiol resulting in behavioral estrus, whether coming off of a pregnancy or having a first estrus
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33
Q

stimulates mammary duct development

A

estrogen

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34
Q

True/False: Circulating Leptin is directly related to body fatness and may function to inform the GnRH secreting neurons of the nutritional status of the female

A

T

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35
Q

True/False: Decreases in progesterone beginning about 5 days before menses results in the development of premenstrual syndrome (PMS) in many women and is associated with increased tension, anger and anxiety

A

True

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36
Q

proestrus

Characteristic ovarian structures seen at the time:

Estrogen to progesterone ratio:

A

Ca + growing follicles

E/P ratio increasing

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37
Q

True/False: Progestogen alone is placed in most oral contraceptives (birth control pills) and taken daily over a 21 day period to mimic the presence of a CL

A

False

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38
Q

estrus

Characteristic ovarian structures seen at the time:

Estrogen to progesterone ratio:

A

ovulatory follicles

E/P ratio maximal

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39
Q

Discuss the 2-Cell, 2-Gonadotropin Model of Follicular estrogen synthesis.

A
  • The 2-cell,2-Gonadotropin model of follicular estrogen synthesis is:
    • leutenizing hormones stimulate the theca interna cells to produce androgens and FSH
    • This stimulates granulosa cells to produces estrogens from those androgens produced by the theca interna cells
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40
Q

Describe the steps required to conduct in vitro fertilization (IVF) in an infertile couple using intracytoplasmic sperm injection (ICSI), a procedure used when insufficient viable sperm and present in the males ejaculate for normal fertilization to occur. Be specific about each step from gamete collection through to embryo placement in the female tract as discussed in class. BE SPECIFIC

A
  1. semen collection
  2. semen evaluation and preparation
    1. evaluated to see if the man is producing sufficient viable sperm for conventional IVF
      1. Criteria
        1. adequate sperm concentration in ejaculate (>20 million sperm/ml)
        2. adequate numbers of viable sperm (50% motility)
        3. low number of abnormal sperm
  3. ovarian stimulation
    1. increasing the number of oocytes increases probability of successful fertilizaiton and embryo development
      1. Begins with an injection of FSH (or FSH-like) hormone anc concludes with HCG
        1. FSH induces the growth of multiple growing follicles
        2. HCG (LH-like) promotes follicular maturation and growth coupled with elevated follicular estradiol secreation
  4. oocyte retrieval and preparation
    1. aspirated from large antral follicles
    2. placed in a dish mimicking the uterine enviroment
    3. A single sperm is injected inside the oocyte ( intracytoplamic) and induce fertilization on 2-3 high quality embryos
  5. embryo transfer
    1. These fertilized embryos are placed in the uterus after “matching” the environment/condiotns of the new embryos and the uterus
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41
Q

during spermatogenesis, which sperm producing cells have gone through the first and second meiotic divisions

A

spermatid

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42
Q

how is colostrum formed

A

high pressure within the mammary duct system, which breaks in tight junctions between the mammary secretory cells in alveoli allowing blood plasma to enter alveolar lumen

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43
Q

increases collegians activity by theca internal cells forming a stigma

​Role in the ovulatory process?

A

progesterone

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44
Q

GnRH

Site of synthesis?

function?

A
  • hypothalamus
  • stimulates LH and FSH secretion
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45
Q

True or False: Colostrum is a result of increased pressure in the lumen of alveoli prior to offspring suckling which breaks the tight junctions between the mammary secretory cells

A

True

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46
Q

True/False: the collection of embryos from the uterus of donor cows and their transfer into recipient females should only be done after hatching of the blastocysts from the zona pellucida

A

False

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47
Q

What is the specific reason why women menstrate (suffer endometrial loss) and livestock species do not? Be specific about the hormonal changes involved and their impact on the endometrium.

A
  • Women suffer menstration because their CL secretes progesterone and estradiol, while livestock species only secrete progesterone
  • The progesterone causes the endometrium to secrete uterine milk, while estradiol results in endometrial thickening, valve growth and increased blood flow
  • When these hormones stop, the endometrial lining sluffs off–> menstration
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48
Q

True/False: the anterior pituitary of a prepubertal female is unable to secrete significant amounts of FSH and LH even if stimulated by exogenous GnRH

A

F

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49
Q

induces thickening and cornification of the vestibule

What steroid hormone induces this change?

A

estradiol

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50
Q

Anabolic Steroid

what phase describes this hormone in the male?

A

man made hormone administered to promote muscle growth and performance

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51
Q

This hormone stimulates sex drive and maintenance of the male genital duct system and through the conversion of DHT promotes a male phenotype

A

testosterone

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52
Q

increases the infiltration of white blood cells into the uterus

What steroid hormone induces this change?

A

estradiol

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53
Q

True or False: The primary oocyte undergoes the first meiotic division at ovulation in cattle, sheep, and pigs, while the second meiotic division occurs at the time of fertilization

A

True

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54
Q

stimulates synthesis and secretion of lactose- initiates lactogenesis

A

prolactin

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55
Q

belong to a class of polypeptide hormones which exhibit the longest half lives in the blood stream

A
  1. FSH
  2. HCG
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56
Q

Inhibin

Site of synthesis?

function?

A
  • sertoli cells
  • inhibits FSH secretion
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57
Q

period of maximal secretion of a watery mucous by the cervix

A

estrus

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58
Q

True/False: Lactating women on a high plane of nutrition return to cyclicity later postpartum than lactating women on a low ,plane of nutrition

A

F

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59
Q

Fully discuss, how increased cortisol production by the bovine fetal adrenal prepares the fetus for life outside the uterus, and how this elevated fetal cortisol initiates the hormonal events resulting in cervical softening, delivery of the fetus and delivery of the placenta during the process of parturition. Be specific about the source of the hormones, and the location of their receptors in the gravid uterus.

A
  1. Step 1: Preparatory Phase (cervical softening and initiation of myometrial contractions)
    1. as fetal cortisol continues to increase it causes:
      1. a decrease in progesterone production by the placenta and/or CL
        1. an increase in PGF2alpha by the uterine endometrium and placenta
        2. the increase in PGF2alpha and estradiol abolish the progesterone block –> myometrium begins to contract
        3. PGF2alpha also kills the CL of all species, causing a further decline in progesterone and the dying CL releases relaxin which softens the cervix and opens the birth canal by opening the pelvic ligament
  2. Step 2: Expulsion of the Fetus
    1. increased estrogen causes the development of gap junctions between mymetrial cells and increases nubmers of PGF2alpha and oxytocin receptors on the myometrial cells –> initiation of directional uterine contractions
    2. Fetus is pushed against the inside of the cervix, exposing sensory receptors signaling oxytocin release.
    3. Oxytocin stimulates powerful peristaltic contractions which ruptures the allantois
    4. Fetus is forced into the birth canal and amnion ruptures
    5. Ab muscles finish expelling fetus via contractions
    6. Fetal Maturation is driven by cortisol
      1. cortisol drives surfactant production
        1. a protein that leads to the opening of the lungs
  3. Step 3: Expulsion of Fetal Membranes
    1. Expulsion of fetal membranes requires that chorionic villi become dislodged from the crypts on the maternal side of the placenta
  4. requires continued uterine contractions–> oxytocin release
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60
Q

True/False: Acrosin, an enzyme released during the acrosome reaction allows the sperm to penetrate the vitelline membrane

A

False

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61
Q

True/False: dyhydrotestosterone secretion from the leydig cells causes the development of the mesonephric tubules and ducts into the male genital duct system which includes the efferent ductules, epididymis, vas deferens

A

F

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62
Q

Describe the acrosome reaction from the binding of the sperm head to the zona pellucid through the fusion of the male and female pronucleus

A
  1. plasma membrane of the sperm head fuses with the outer acrosomal membrane
    • vessiculation and loss of acrosomal contents (minus the inner membrane)
  2. Release of acrosomal enzymes allow sperm to digest its way through the Zona Pellucida
  3. After sperm penetrate the Zona Pellucida, the equatorial region of the sperm head fuses with microvilli on the plasma membrane
    • enters the cytoplasm
  4. Granules in the cortex of the oocyte release their contents into the periventricular space
    • seal up the zona pellucida
  5. Microvillar on the surface disappear preventing further binding by other sperm
  6. After entering the eggs cytoplasm it becomes “male” and the nucleus must decondense so that male and female chromosomes may pair up, fusing to form a zygote
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63
Q

FSH

what phase describes this hormone in the male?​

A

stimulates androgen binding protein production by sertoli cells

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64
Q

PGF2alpha

Site of synthesis?

function?

A
  • endometrium
  • kills luteal cells during luteolysis
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65
Q

during gastrulation and hatching of the blastocyst, the Yolk Sac is formed from the following embryonic germ cell layers

A

entoderm + splanchnic mesoderm

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66
Q

elevated secretion of this hormone by an ovulatory follicle causes a surge release of GnRH from the surge center of the hypothalamus

A

estradiol

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67
Q

By the 8 cell stage, each blastomere of the embryo of this specie is no longer totipotent

A

pig

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68
Q

True or False: The composition of alveolar milk is changed significantly as it travels through the duct system to the teat

A

False

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69
Q

species which ejaculates semen as a single fraction

A

ruminant

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70
Q

specie who normally have only 2 teats and associated mammary glands on the inguinal region of the mammary ridges

A
  • goat
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71
Q

the signal for maternal recognition of pregnancy produced by the ruminant conceptus, which maintains the luteal lifespan and progesterone secretion in the ruminant is

A

interferon proteins

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72
Q

uniform distribution of estrous cycles throughout the year

Type of Cyclicity?

Specie who exhibits this cyclicity?

A
  1. polyestrus
  2. pig
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73
Q

differentiates mammary secretory cells

A

free cortisol

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74
Q

distal centriole

A

gives rise to the axoneme

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75
Q

lining the uterine lumen- have a very high mitotic rate

A

pseudostratified columnar

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76
Q

an implant containing a melatonin antagonist during inserts will initiate early cyclically in this specie

A
  1. mare
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77
Q

PGF2a

Class?

Where is it synthesized?

Target tissue?

A
  1. fatty acid
  2. endometrium
  3. cells of the CL
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78
Q

hormone which exerts a positive feedback on the surge center to release a large amount of GnRH

A
  1. Estradiol
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79
Q

True/False: administration of estrogen when the early embryo is in the isthmus of the oviduct will speed up its transport into the uterus thereby killing it

A

F

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80
Q

results from the release of cortical granules from the egg cell cytoplasm and is the major block of polyspermy

A

Zona reaction

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81
Q

True/False: Menopause occurs at the average age of 51 in western countries and results from a depletion of GnRH in the hypothalamus

A

False

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82
Q

dog

placental type

number of tissue layers separating fetal and maternal blood stream

placental shape

A

endotheliochorial placenta

four layers

zonary shaped

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83
Q

steriociliated columnar

Site in male or female repro tract:

Function is in that site:

A

Site in male or female repro tract: head of epididymis

Function is in that site: brush off cytoplasmic droplet

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84
Q

increases contraction of ovarian smooth muscle and releases lysosomal enzymes from the granulose cells to further weaken the follicular wall for oocyte expulsion

​Role in the ovulatory process?

A

prostaglandin F2a

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85
Q

True or False: A morula is a solid ball of blastomeres, while a blastocyst contains inner cell mass cells surrounded by trophectoderm cells and a fluid filled cavity called the blastocoele

A

True

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86
Q

When administered in high doses over a prolonged period of time it will kill the leydig cells resulting in sterility

A

anabolic steroid

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87
Q

True/False: Zona protein 3 is a glycoprotein receptor which only allows sperm of the same species to bind to the zona pellucida

A

True

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88
Q

sheep

signal that maintains luteal function in specie during maternal recognition of preg.

CL indep. or dep.

A

interferon

CL independent specie

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89
Q

inhibits prolactin binding to mammary secretory cells

A

estrogen

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90
Q

True/False: Following AI in cows, less sperm are lost by retrograde flow if they are deposited in the mid-cervix than if they are deposited in the uterus

A

False

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91
Q

necrotic tips form during elongation where these 2 parts of the fetal placenta don’t fuse

A

chorion and allantois

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92
Q

cow

placental type

number of tissue layers separating fetal and maternal blood stream

placental shape

A

syndesmochorial placenta

five layers

cotyledonary shaped

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93
Q

True/False: Menses results from the decrease in estradiol and progesterone which occurs during luteolysis (death of the CL), and causes PGF2alpha release which prevents blood flow through the spiral arterial supplying the endometrium

A

True

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94
Q

True/False: differential embryonic growth away from the testes and the growth and subsequent retraction of the gubernaculum causes the testes to descend through the inguinal ring into scrotum

A

T

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95
Q

True/False: 50% of the 6 million annual pregnancies in the US are unplanned

A

True

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96
Q

Mammogenesis definition

A

growth and development of the gland between birth and puberty

between birth and puberty, growth is isometric

between puberty and conception growth is allometric

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97
Q

specie in which ovarian PGF2a kills the CL

A
  1. human
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98
Q

Describe the sequence of hormonal events which time lactogenesis (initiation of milk secretion) with the delivery of the calf at parturition the cow. (Hint: Remember that progesterone progressively declines over the last week of gestation in the cow.)

A
  1. a couple weeks before parturition, progesterone decreases thus causing the stimulation of corticosteriod binding globulin by the liver to decrease
  2. as free cortisol is increased in the blood, it enters and begins to differentiate mammary secretory cells
  3. placental estradiol levels begin to increase markedly in the blood which increases pituitary secretion of prolactin but prevents it from binding to its receptors on mammary secretory cells
  4. at parturition, the placenta is expelled and estradiol levels drop, allowing prolactin to bind to mammary secretory cells and stimulate lactose synthesis.
  5. As lactose is synthesized within the mammary secretory cells, they draw in water by osmosis which initiates milk secretion
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99
Q

hormone which exerts negative feedback on GnRH secretion by the surge center and tonic release center

A
  1. Progesterone
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100
Q

process whereby seminal plasma proteins are removed from the sperm head to allow enzyme release from the acrosome

A

capacitation

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101
Q

True/False: in the beef cow 3 or more suckling bouts by her offspring per day are required to keep blood LH low and to maintain lactational anestrus

A

T

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102
Q

True/False: The failure of cows, but not other livestock species to develop necrotic tips on her placenta is unique to the cow, and results in freemartin heifers when they are born co-twin to a bull calf

A

T

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103
Q

enzymes producing this hormone are located on the smooth endoplasmic reticulum

A
  1. Progesterone
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104
Q

What structures are found on the surface of the ovary during proestrus of the cycle

A

growing follicles and CA

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105
Q

proximal centriole

A

gives rise to the attachment site for the sperm tail

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106
Q

exhibits clusters of estrous cycles during the fall and winter only

Type of Cyclicity?

Specie who exhibits this cyclicity?

A
  1. seasonally polyestrus (short day)
  2. sheep
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107
Q

True/False: presence of a male will reduce age at puberty in prepubertal gilts or heifers

A

T

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108
Q

day 1-6

Stage of the estrous cycle to the first PGF2alpha injection:

What days of the estrous cycle each group will be 14 days later:

A
  1. CL unaffected
  2. days 15-20
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109
Q

True or False: the time required for uterine involution is less for the dairy cow than the suckled beef cow

A

False

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110
Q

In livestock species, testicular temperatures must be maintained 4-6deg C cooler than males body temperature if spermatogenesis is to continue normally. Compare and contrast the efficiency of testicular cooling the the bull and ram which have pendulous testes with the boar and stallion which do not. Be specific about the cooling mechanisms involved.

A

Due to meiosis, the testes must be cooler than body temp. In the bull and ram, the arterial cooling system (the pampiniform plexus), the skeletal cremaster muscle** and the smooth **tunica dartos muscle are all able to work more efficiently to keep the testes cool because they’re farther from the body cavity, unlike the boar and stallion.

*The pampiniform plexus cools by using a “radiator” system in the arteries

*the cremaster muscle can temporarily hold testes up

*the tunica dartos muscle maintains tone

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111
Q

True/False: In Andropause which occurs between 70 and 80 yrs of age in men, at which time testosterone production has declined to about 50% of normal, completely stopping spermatogenesis and resulting in infertility.

A

False

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112
Q

these hormones are mammogenic, but inhibit mammary secretory cell differentiation, and lactogenesis until they are removed at the end of pregnancy

A

estrogen

progesterone

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113
Q

the umbilical cord forms at the sight where this part of the placenta grew out of the embryo

A

Allantois

114
Q

in the female, puberty is reached when the negative feedback effect of estrogen declines sufficiently to allow the tonic GnRH release Center of the hypothalamus to grow ovulatory size follicles on the ovaries

A

true

115
Q

GnRH

Class?

Where is it synthesized?

Target tissue?

A
  1. peptide
  2. hypothalamus
  3. anterior pituitary
116
Q

Specie that have a uniform distribution of villi covering the entire outer surface of the chorion for attachment to the uterus

A
  1. Diffuse
    1. Pig
    2. Mare
117
Q

mare

placental type

number of tissue layers separating fetal and maternal blood stream

placental shape

A

eptheliochorial placenta

six layers

diffuse shaped

118
Q

True or False: What differentiates mammals from other groups of animals is live birth and the presence of a mammary gland

A

False

119
Q

True/False: Amenorrhea is the human equivalent to anestrus and can result from menopause low nutritional intake or lactation

A

T

120
Q

True/False: When collecting semen from a bull with an artificial vagina, both temperature and pressure are important to stimulate ejaculation, while only an optimal temperature is required for the boar

A

False

121
Q

True/False: Almost all mammalian females nursing young experience lactational anestrus except for horses and alpacas

A

T

122
Q

oxytocin

Class?

Where is it synthesized?

Target tissue?

A
  1. peptide
  2. hypothalamus
  3. myoepithelial cells of mammary
123
Q

mitochondria

A

spiral around the middle piece of the sperm tail

124
Q

bound to CBG when progesterone is elevated during gestation but is released when progesterone declines near term

A

free cortisol

125
Q

True/False: Viagra causes a prolonged erection because it inhibits the conversion of cGMP to GMP thus prolonging vasodialation

A

True

126
Q

increased follicular blood flow and fluid uptake

Role in the ovulatory process?

A

prostaglandin E2 and Histamine

127
Q

period when the uterine lining produces and secretes increasing quantities of the PGF2a into the blood to kill the CL

A

proestrus

128
Q

True/False: in the sheep, low melatonin produced by the pineal gland during the spring and summer results in low kisspeptin secretion resulting in reduced GnRH secretion by the tonic release center of the hypothalamus resulting in anestrus

A

T

129
Q

in these species PGF2a receptors appear on luteal cells after day 6 of the estrous cycle, thus exogenous PGF2a is ineffective in inducing luteolysis prior to that time

A
  1. mare
  2. cow
  3. sheep
130
Q

True/False: The incidence of Downs syndrome (trisomy 21) markedly increases in women giving birth after age 37 and is though to be due to prolonged oocyte storage in the woman’s ovary

A

True

131
Q

True/False: the posterior lobe of the pituitary forms from Rathke’s pouch which is composed of oral ectoderm, and develops an endocrine function

A

F

132
Q

Proliferative Phase

Cell types?

A
  1. type A spermatagonia
  2. Type I spermatagonia
  3. Type B spermatagonia
133
Q

True/False: Superfecundation in a dog is a result of their long duration of estrus and the prolonged interval after the onset of estrus when fertilization can occur

A

True

134
Q

period when sperm are deposited in the female tract and transported by uterine peristalsis to the utero- tubal junction by peristalsis

A

estrus

135
Q

During metestrus of the cycle the estradiol/progesterone ratio is

A

decreasing

136
Q

True/False: the bull and ram and dog are short copulators while the boar, tomcat and camelids are sustained copulators

A

False

137
Q

receptors for steroid hormones are located inside target cells, while receptors for peptide, protein and fatty acid hormones are located on the plasm membrane

A

true

138
Q

Describe the ejaculatory muscle in the bull. Be specific about the mechanisms involved.

A
  1. Urethralis muscle: propels sperm through the pelvic urethra
  2. bulbospongiosus muscle : pushes sperm from the pelvic urethra to the penile urethra
  3. ischcaveraosus muscle: clamps off venous return
  4. retractor penile muscle : relaxes allowing erection​
139
Q

True or False: the trophectoderm cells surrounding the blastocyst develop gap junctions between them to allow free exchange of information, while the inner cell mass cells develop tight junctions to hold the inner cell mass together

A

False

140
Q

LH

Site of synthesis?

function?

A
  • anterior pituitary
  • stimulates testosterone production by the theca interna cells of the antral follicles
141
Q

species which deliver PGF2a locally from the ipsilateral uterine horn to the ovary by way of transfer from the uterine vein to the ovarian artery

A
  1. cow
  2. sheep
  3. pig
142
Q

True/False: Sexual preparation in the bull, increases sperm numbers in the ejaculate through oxytocin release from the posterior pituitary which stimulates contracitons of the distal tail of the epididymis and ductus deferens

A

True

143
Q

True/False: the blood-testis barrier must be formed before spermatogenesis is initiated in a male to prevent autoimmune reactions which can destroy the developing germ cells

A

T

144
Q

True/False: Sows return to estrous and ovulate 4-8 days after weaning of their litter

A

T

145
Q

dissolves the blood clot in the CH and remodels the follicle into a CL

​Role in the ovulatory process?​

A

plasmin

146
Q

True/False: While antimullerian hormone produced by the sertoli cells of the genetic male is necessary for the regression of the paramesonephric ducts, it does not regress the structures derived from the urogenital sinus which include the posterior vagina, vestibule, and external genitalia

A

T

147
Q

True/False: dairy female are bred to express a very feminine phenotype and thus do not often express masculine traits even when exposed to dihydrotestosterone from the male co-twin

A

T

148
Q

FSH

Site of synthesis?

function?

A
  • ***
  • stimulates estradiol production by granulose cells of the antral follicles
149
Q

pseudostratified columnar

Site in male or female repro tract:

Function is in that site:

A

Site in male or female repro tract: lining of uterus

Function is in that site: high mitotic rate

150
Q

True or False: In most mammalian species sperm capacitation occurs in the male accessory sex glands prior to ejaculation

A

False

151
Q

progesterone

Class?

Where is it synthesized?

Target tissue?

A
  1. steroid
  2. cells of CL
  3. uterine glands
152
Q

True/False: conventional in-vitro-fertilization (IVF) is used when an ejaculate contains sufficient viable sperm to fertilize ova normally by crossing the surrounding membrane layers

A

True

153
Q

diestrus

Characteristic ovarian structures seen at the time:

Estrogen to progesterone ratio:

A

CL

E/P ratio minimal

154
Q

a neuro-endocrine reflex starts when a sensory afferent neuron in the teat is stimulated which synapses with an interneuron in the spinal cord which carries the signal up the paraventricular nucleus of the hypothalamus, where it synapses with oxytocin neurosecretory cells, stimulating the posterior pituitary to release oxytocin into the blood stream

A

true

155
Q

Oxytocin

Site of synthesis?

function?

A
  • ***
  • stimulates myoepithelial cell contraction during milk letdown
    *
156
Q

nice coarse outer fibers

A

provide stability to the sperm tail

157
Q

females whose interval with parturition to uterine involution is shortest due to minimal damage to the uterine wall

A
  • pig
  • mare
158
Q

period when the fertilized egg is transported through the isthmus of the oviduct into the estrus

A

metestrus

159
Q

Chorion

A
  • not vascularized and acts as a protective outer covering of the conceptus
  • somatic mesoderm + trophectoderm
160
Q

hormones belonging to a class of hormones with the longest half-lives in the blood stream

A
  1. FSH
  2. HCG
161
Q

goat

signal that maintains luteal function in specie during maternal recognition of preg.

CL indep. or dep.

A

interferon

Cl dependent specie

162
Q

period when the embryo can be killed by an injection of estradiol

A

***

163
Q

What are the 4 major events of the puerperium?

A

myometrial contractions and expulsion of

endometrial repair

resumption of ovarian function

elimination of bacterial contamination of the reproductive tract

164
Q

Allantois

A
  • develops the first blood vessels in the conceptus and is called the primitive gut
  • splanchnic mesoderm + endoderm
165
Q

True/False: Flow cytometry can be used to sex semen samples based on the fact that chromosomes contain more genetic material than Y chromosomes

A

True

166
Q

HCG

Class?

Where is it synthesized?

Target tissue?

A
  1. glycoproteins
  2. human placenta only
  3. cells of the CL
167
Q

How does Alpha Fetoprotein found in the blood of both the male and female fetuses prevent the inactivation of the GNRH Surge Center in the female but not in the male fetus?

A

Alpha-fetoprotein binds tightly to estradiol, preventing it from crossing the blood-brain-barrier in females. In males, testosterone is allowed to cross that barrier and inactivates the GNRH surge center.

168
Q

Testosterone

Site of synthesis?

function?

A
  • leydig cells
  • exerts a negative feedback on GnRH release in the male
169
Q

True/False: a cervical Os and fornix are found in ruminants, pigs, mares, and humans

A

F

170
Q

True/False: The fertile period during the menstrual cycle when sperm deposition can result in pregnancy occurs during the last 5 to 6 days of the follicular phase through the day of ovulation

A

True

171
Q

allows sperm to digest a path through the zona pellucida and into the perivitelline space

A

Acrosin

172
Q

True or False: Lochia is necrotic placental and endometrial remnants left over after pregnancy which is expelled through the vulva

A

True

173
Q

True/False: a freemartin is a heifer calf born co-twin to a bull which has been exposed to antimullerian hormone from her co-twin which has regressed all or part of her mullarian ducts and is infertile

A

T

174
Q

Which hormone listed below has intra-cellular receptors in the cytoplasm or nucleus of its target cells

A

cortisol

175
Q

stimulates mammary glandular development

A

progesterone

176
Q

female where the chorionic epithelium is bathed in maternal blood

A

woman

177
Q

Will the removal of the uterus affect the luteal lifespan in a: dog?

A

removal of the uterus will not affect the lifespan of the CL

178
Q

True or False: Rennin is secreted by the gastric epithelium of very young ruminants and causes milk proteins (caseins) to form curds to facilitate protein digestion

A

True

179
Q

the organelle used by the cell which produces many copies of a few proteins for export is

A

rough endoplasmic reticulum

180
Q

Meiotic Phase

Cell types?

A
  1. primary spermatocyte
  2. secondary spermatocyte
181
Q

True/False: Fall born lambs receiving adequate nutrition reach puberty at 5-6 months, while spring born lambs reach puberty at 10-12 months

A

F

182
Q

female which forms binucleate cells which migrate out of the chorionic epithelium into the uterine luminal epithelium and secrete placental lactogen

A

cow

183
Q

List the requirements of a good semen extender used for AI

A
  1. minimize cold shock
  2. prevent microbial growth
  3. maintain viability
  4. low in cost
  5. isotonic
  6. be a good buffer
  7. provide nutrients
184
Q

When the embryo reaches this stage of development it is a solid ball of blastomeres still encased in the zona pellucida

A

morula

185
Q

Describe the afferent and efferent pathways of a simple neural reflex and contrast this with the afferent and efferent pathways followed by a neuroendocrine reflex and give an example of each. Be specific.

A

Simple Neural Reflex

  • An afferent neuron is stimulated, causing it to synapse with an interneuron in the snpinal cord.
  • That neuron synapses with an efferent neuron at the same location in the spinal cord which causes a response
  • an example would be testicular tone and sweating
  • afferent & efferent= neuronal

Neuroendocrine Reflex

  • An afferent neuron is activated
  • It then synapses to an interneuron in the spinal cord
  • This neuron then synapses with another afferent neuron which travels up the spinal cord to the Hypothalamus
  • The Hypothalamus then releases neurohormones
  • an example of this would be milk letdown due to the release of oxytocin spurred by washing/suckling of a cow’s teats
  • Afferent => neuronal efferent => hormonal
186
Q

True or False: During cervical transport, viable sperm that encounter high viscosity sialomucin swim through the cervix with ease, while sperm encountering the low viscosity sialomucin are flushed out of the tract

A

False

187
Q

True/False: in women, the death of the CL results from the uterine release of PGF2alpha which travels to the ovary and kills luteal cells

A

False

188
Q

True or False: The secretion of milk protein and lactose by the mammary secretory cell into the alveolar lumen removes part of its apical cell membrane which is replaced by the secretion of milk fat

A

False

189
Q

prevents sperm of a different species from fertilizing an oocyte

A

ZP3 receptors

190
Q

True or False: Loss of sperm from the female tract occurs mainly through the process of phagocytosis and retrograde flow

A

True

191
Q

True/False: in the female, the onset of puberty is a result of a progressive decrease in hypothalamic sensitivity to the negative feedback effects of estradiol

A

T

192
Q

female in which endometrial cups are developed to stimulate the development of accessory corpora lutea

A

mare

193
Q

A steroid secreting cell can be identified due to the significant amounts of smooth endoplasmic reticulum in its cytoplasm

A

true

194
Q

capacitation involves removal of seminal plasma proteins from the sperm head to allow fertilization to occur

A

true

195
Q

lining the efferent ductules for water resorption and movement of contents

A

microvillar and ciliated columnar

196
Q

specie that have a broad band of villi around the chorion near the middle of the conceptus for attachment to the uterus

A
  1. Zonary
    1. cat
    2. dog
197
Q

the so called second messenger activated when a polypeptide hormone binds to its membrane receptor on its target cell

A

cyclic AMP

198
Q

Differentiation Phase

Cell types?

A
  1. spermatazoa
  2. spermatids
199
Q

True/False: the follicular phase in a women’s menstrual cycle occupies only 20% of the length of the menstrual cycle, while in the estrous cycle of the cow and sheep it occupies 50% of estrous cycle length

A

F

200
Q

Urthralis muscle

A

propels semen through the pelvic urethra

201
Q
A
202
Q

True/False: there is evidence that the initiation of high frequency low ampulite GnRH pulses can be advanced by exposure to increased glucose and or fatty acids concentrations in the blood

A

T

203
Q

an implant containing melatonin during anestrus will initiate early cyclicity in this specie

A
  1. sheep
204
Q

True/False: Primary ovarian follicles do not produce estradiol due to the absence of theca internal cells which convert cholesterol to testosterone which is converted to estradiol by the granulosa cells of the follicle

A

T

205
Q

True/False: in the 17th and 18th centuries epigenists proposed that miniature creatures were contained in the egg or sperm

A

F

206
Q

increases the secretion of uterine gland secretion of uterine milk

What steroid hormone induces this change?

A

progesterone

207
Q

necrotic tips form at each end of an elongating pig embryo when these parts of the placenta fail to fuse together

A

Allantois

Chorion

208
Q

promotes genital swelling

What steroid hormone induces this change?

A

estradiol

209
Q

specie that have numerous discrete button-like structures called cotyledons over the surface of the chorion which are each covered with chorionic villi for attachment to caruncles on the uterine wall

A
  1. Cotlyondary
    1. goat
    2. cow
210
Q

Glycoprotein hormones have a greater half-life in the bloodstream than protein or peptide hormones

A

true

211
Q

LH

what phase describes this hormone in the male?

A

stimulates the leydig cells to produce testosterone

212
Q

What part of the male reproductive duct system is not derived from the mesonephric duct?

A

urethra

213
Q

True or False: Each blastomere (embryonic cell) of an 4 cell pig embryo and an 8 cell cow embryo are totipotent

A

True

214
Q

Will the removal of the uterus affect the luteal lifespan in a: pig?

A

removal of the uterus will prolong the lifespan of the CL

215
Q

Lactogenesis

A

intitation of milk secretion at term and results from hormonal changes

216
Q

Which portion of the female reproductive is not affected by the antimullerian hormone in a freemartan female?

A

vulva

217
Q

hormone collected from the urine of pregnant women and used for pregnancy diagnosis

A
  1. HCG
218
Q

True/False: Teasing a male in the presence of a female in estrus can significantly increase the number of sperm ejaculated

A

T

219
Q

True/False: time required for ejaculation differs due to whether the male has a fibroelastic or a vascular penis structure

A

T

220
Q

females with decidua

A

woman

dogs

221
Q

True/False: During the acrosome reaction fusion of sperm plasma membrane and outer acrosomal membrane leads to vesiculation and loss of the acrosomal enzymes

A

True

222
Q

lining the head of the epididymis to remove sperm cytoplasmic droplet

A

steriociliated columnar

223
Q

True/False: When using oral contraceptives there is no way of knowing whether pregnancy is being prevented due to inhibition of ovulation or minimizing the chance of implantation

A

true

224
Q

True/False: prenatal exposure of a female fetus to a large dose of estradiol results in decreased estrous behavior and an increase in male-like behavior

A

True

225
Q

Will the removal of the uterus affect the luteal lifespan in a: mare?

A

removal of the uterus will prolong the lifespan of the CL

226
Q

increases uterine gland growth

What steroid hormone induces this change?

A

estradiol

227
Q

days 18-21

Stage of the estrous cycle to the first PGF2alpha injection:

What days of the estrous cycle each group will be 14 days later:

A
  1. CL die normally over the next 3 days
  2. days 11-14
228
Q

ciliated and secretory columnar

Site in male or female repro tract:

Function is in that site:

A

Site in male or female repro tract: infundibulum and ampula of oviduct

Function is in that site: move and nourish oocytes during maturation

229
Q

True/False: The XY embryo converts the mesonepric kidney and its ducts and tubes into the testis, efferent ductules, epidermis, vas definers and seminal vesicles

A

T

230
Q

True/False: Increases in estradiol at the end of the follicular phase are associated with increased confidence and aggressiveness in many women

A

True

231
Q

Female with the fewest tissue layers separating the fetal and maternal blood streams

A

Woman

232
Q

ciliated and microvillar columnar

Site in male or female repro tract:

Function is in that site:

A

Site in male or female repro tract: efferent ductules

Function is in that site: movement of nonmotile sperm and water restoration

233
Q

in the mare and sow, the majority of sperm are deposited in the cranial vagina during mating and are dependent on cervical transport to reach the uterus

A

false

234
Q

females with the greatest number of tissue layers separating the fetal and maternal blood streams

A
  • pig
  • mare
235
Q

in the pig, the correct type of insemination is

A

intracervical insemination

236
Q

period when secretion of uterine milk into the uterine lumen is maximal

A

diestrus

237
Q

Yolk sac

A
  • develops the first blood vessels in the conceptus and is called the primitive gut
  • splanchnic mesoderm + endoderm
238
Q

The “morning after pill”, used to prevent unwanted pregnancy in women, contains a very long acting estradiol and is administered the day after unprotected sex. In your answer, provide information about the specific part of the female reporductive tract affected by this steroid and what changes are initiated in that part and why this prevents pregnancy

A

At the time of estrus, estrogen ratio is at a maximum. This causes peristaltic contractions to move toward the ampula and uterotubal junction allowing capictated sperm to arrive at the oocyte. The long acting estradiol causes the contractions to continue to move toward the ampillary-isthmus junction stopping the now fertilized egg from traveling through the isthmus to reach the uterus. By the time the estradiol decreases, it will be too late for the egg to implant thus causing intraception of pregnancy.

239
Q

acrosome

A

forms the cap of the sperm head and contains hydrolytic enzymes

240
Q

Electroejaculation is the preferred method of semen collection in conscious boars

A

false

241
Q

increases blood flow to the reproductive tract

What steroid hormone induces this change?

A

estradiol

242
Q

exhibits clusters of estrous cycles during the spring and summer only

  • Type of Cyclicity?*
  • Specie who exhibits this cyclicity?*
A
  1. seasonally polyestrus
  2. mare
243
Q

Will the removal of the uterus affect the luteal lifespan in a: cow?

A

removal of the uterus will prolong the lifespan of the CL

244
Q

results from the disappearance of microvillar on the surface of the oocyte in response to contact by the fertilizing sperm

A

vitelline block

245
Q

a simple neural reflex begins when a sensory afferent neuron is stimulated which synapses with an interneuron in the spinal cord, which itself synapses with a motor efferent neuron at the same location in the spinal cord to carry the signal back to the tissue. Very rapid response (i.e. ejaculation)

A

true

246
Q

ischiocavernosus muscle

A

clamps off venous return from the penis causing penile extension

247
Q

stratified squamous

Site in male or female repro tract:

Function is in that site:

A

Site in male or female repro tract: lining of vestibule

Function is in that site: protect from physical damage

248
Q

True or False: The collection of embryos from the uterus of donor cows and their transfer into recipient females should only be done after hatching of the blastocysts from the zona pellucid

A

False

249
Q

metestrus

Characteristic ovarian structures seen at the time:

Estrogen to progesterone ratio:

A

CH

E/P ratio decreasing

250
Q

True/False: in the genetic male, SRY gene, located on the Y chromosome produces an SRY protein resulting in testis development, which occurs several weeks before the normal development of the ovary in a genetic female of the same species

A

T

251
Q

True or False: If inner cell mass cells from a goat blastocyst are collected and injected into the blastocyst of a sheep embryo containing its own inner cell mass, and the injected embryo placed into the uterus of a goat, it will give birth to a deep (cross between sheep and goat)

A

False

252
Q

this part regresses at implantation when the choir-allantonic membrane forms and attaches to the uterine wall to begin to take up nutrients directly from the maternal blood

A

Yolk Sak

253
Q

True/False: Developing germ cells are connected by intercellular brides so that the cytoplasm of an entire cohort of cells are interconnected. This provides communication between cells that contribute to the synchronized development of these cells

A

True

254
Q

Allantois

A
  • -thrust out from the hind gut of the embryo, and expands to vascularize the chorion
  • splanchnic mesoderm + endoderm
255
Q

Why does the cow commonly exhibit retained placentae following premature births or late term abortions while the sheep does not. Be specific

A

Although both species have cotyledonary placentas the ewe (and goats) have concave cotyledons, whereas in the cow (and giraffe) the cotyledons are convex. The convex shape leads to a greater susceptibility to retaining the placenta since it is more difficult to separate maternal and fetal tissue

256
Q

The pairing of homologous chromosome only occurs during mitosis, but not during meiosis, and functions to allows exchange of allelic forms of genes from one chromosome to the other

A

false

257
Q

True or False: The trophectoderm cells surrounding the blastocyst develop gap junctions between them to allow a free exchange of information, while the inner cell mass cells develop tight junctions to hold the inner cell mass together

A

False

258
Q

True or False: From birth to conception the mammary glands grow at the same rate as the rest of the body, but after puberty they begin to grow at an increased rate under the stimulus of estradiol (duct development) and progesterone (glandular development).

A

True

259
Q

Inhibin

what phase describes this hormone in the male?​

A

Inhibits FSH secretion by the anterior pituitary gonadotrophs

260
Q

how does milk ejection happen

A

When sensory neurons in the teat or nipple are stimulated by tactile stimuli, a neural signal is sent to the interneuron of the spinal cord which convey the signal to paraventricular nucleus which results in oxytocin release from posterior pituitary into blood

261
Q

specie that have a small disc covered with chorionic villi for attachment to the uterus

A
  1. Discoid
    1. woman
262
Q

female whose young DO NOT have an absolute requirement for colostrum if they are to survive

A
  • dog
  • cat
  • woman
263
Q

This hormone binds to its receptors on sertoli cells and maitains spermatogenesis at an optimal level

A

FSH

264
Q

lining the urethra to allow stretching

A

transitional

265
Q

days 7-17

Stage of the estrous cycle to the first PGF2alpha injection:

What days of the estrous cycle each group will be 14 days later:

A
  1. all CL killed in 3 days
  2. day 11
266
Q

pig

signal that maintains luteal function in specie during maternal recognition of preg.

CL indep. or dep.

A

estradiol

CL dependent specie

267
Q

Relaxin

Site of synthesis?

function?

A
  • ***
  • causes cervical softening during parturition
268
Q

True/False: Sperm recovered from the tail of the epididymis cannot fertilize oocytes in vitro unless they first come in contact with secretions from the male accessory glands

A

F

269
Q

True or False: Resumption of ovarian activity occurs sooner in the dairy cow than in the suckled beef cow

A

True

270
Q

True/False: Cutting all the nerves entering and leaving the mammary gland shortens lactational inserts in the beef cow

A

F

271
Q

True/False: Along the length of the seminiferous tubule, all germ cells are at a similar developmental stage, allowing for continuous production of spermatazoa

A

False

272
Q

exhibits one estrous cycle per year

Type of Cyclicity?

Specie who exhibits this cyclicity?

A
  1. monoestrus
  2. wolf
273
Q

True/False: the number of GnRH secreting neurons, their morphology and distribution within the hypothalamus are established well before puberty

A

T

274
Q

period when epithelial lining of the vestibule and posterior vagina is the thickest and is cornified

A

estrus

275
Q

List the sequence of specific cellular events that are initiated when LH binds to its membrane receptors on luteal cells and ends with the secretion of progesterone by these cells. Be specific about how the precursor cholesterol enters the cells and what organelles the cells use to convert this cholesterol to progesterone for secretion.

A
  1. Cholesterol travels to luteal cells via the bloodstream
  2. LH binds to specific receptors on the plasma membrane of the luteal cells
  3. The LH receptor complexes activate G proteins which in turn activate adenylate cyclase which converts ATP to cAMP
  4. cAMP enzymes activate the protein kinase enzymes which promote the uptake of cholesterol and store it as mitochondria
  5. Mitochondrial enzymes convert cholesterol into pregnenolone
  6. pregnenolone is then converted into progesterone
276
Q

the uterus of the dog is

A

bicornuate

277
Q

hormones synthesized by neurosecretory cells

A
  1. GnRH
  2. oxytocin
278
Q

simple squamous

Site in male or female repro tract:

Function is in that site:

A

Site in male or female repro tract: visceral vaginal tunic

Function is in that site: slippery layer that prevents testicular adhesions

279
Q

hormone that travels down the hypothalamus- hypophyseal portal system to reach its target cells

A
  1. GnRH
280
Q

covering the outside of the female reproductive tract and prevents adhesions with other organs and tissues

A

simple squamous

281
Q

exerts a negative feedback to inhibit GnRH secretion and reductions of GnRH receptors on pituitary gonadotrophs reducing FSH and LH secretion

What steroid hormone induces this change?

A

progesterone

Mammalian Reproduction (4 decks)

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