Reproduction Flashcards

1
Q

What are the three types of sexual differentiation?

A

Genetic
Gonadal-testes determining genes
Phenotypic -tubular and external structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is SRY?? What happens in absence of this factor?

A

Testis determining factor

Cortical sex cords develop into follicles and medullary sex cords degenerate =female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

In presence of SRY, medullary sex cords differentiate to ______________ cells and cortical sex cords __________.

A

Sertoli

Degenerate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is freemartinism?

A

Male and female co-twins with fused placental

Male produce anti-mullerian hormone and it circulates to female and inhibits her development of internal structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is sex reversal?

A

Disagreement between chromosomal and gonadal sex

XX sex reversal
-XX genotype with testicular development
SRY translocation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the three main classes of homones?

A

Steroids
Peptides
Eicosanoids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How are hormones delivered?

A
Endocrine 
Neuroendocrine 
Paracrine 
Neurocrine 
Autocrine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What hormone is neuroendocrine delivered?

A

Gonadotropin releasing hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Estradiol and FSH are delivered by?

A

Endocrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What hormone is delivered by paracrine delivery?

A

Testosterone

Leydig cells to stertoil cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What hormone is autocrine delivered?

A

Estradiol

Sertoli cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The strength of hormone action depends on?

A

Secretion pattern
Half-life
Receptor density
Affinity receptor-hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the half life of a hormone?

A

The rate at which it is cleared from circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a hormone agonist?

A

Binds to receptor and has the same biological response of the native hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hormone antagonist?

A

Bind to the receptor but it has a weak or not biological effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What hormones are produced in the hypothalamus?

A

GnRH, and Oxytocin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What hormones are produced in the pituitary?

A

FSH, LH, and Prolactin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Protein hormones activate cellular responses by which mechanism?

A

Activate protein kinases via cAMP

Protein kinases produce new protein products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Steroids activate cellular responses by what mechanism?

A

Steroid diffuses through the plasma membrane and nuclear membrane. Bind to receptors and trigger mRNA production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Testosterone is ___________ in a non-reversible enzyme process to produce estradiol

A

Aromatized

Aromatase enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where is Estradiol-17B produced?

A

Follicular cells of ovary, placental

Also small amounts in adrenal, testis, and other sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Where is Estraiol metabolized?

A

Liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Cholesterol is made into adrotenedione in the ______ cells. Adrotenedione is made into estradiol in the ___________cells?

A

Theca

Granulosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the functions of Estradiol?

A
Mediate sexual behavior and secondary sex characteristics 
Uterine development and function
Cervical mucus 
Increase progesterone receptors
Vaginal proliferation 
Mammary development 
Ovulatory LH surge 
Maintain pregnancy 
Bone health
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Progesterone is produced mainly by the ?

A

Corpus luteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the functions of progesterone?

A
Development of uterus
Myometrium 
Closure of cervix, increased viscosity of cervical mucus
Maintain pregnancy 
Mammary development 
Immune function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are progestagens?

A

Class of hormones that bind to progesterone receptors

Progesterone-like actions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Where is testosterone produced?

A

Leydig cells of testes

Small amounts in adrenal and ovaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the function of testosterone?

A
Masculinization 
Maturation of male repro structures 
Spermatogenesis 
Male sexual behavior
Muscle mass and bone density (Anabolic)
Erythropoietics 
Increase BMR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are androgens?

A

Class of compounds binding to adgrogen (testosterone) receptors

Testosterone
Dihydrotestosterone
Androstenedione

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the two functional areas of the female hypothalamus?

A

Tonic and surge centers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Presence of testosterone has what effect on the Brian?

A

“Defeminize” the brain
Testosterone crosses blood brain barrier and converted to estradiol
Estradiol eliminates surge center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

GnRH to the pituitary stimulates the release of?

A

LH and FSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

FSH stimulates what in the female?

A

Follicle growh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are the two feedback pathways of FSH

A

Follicle growth

Graafian follicles - positive feedback with estradiol to hypothalamus to stimulate LH surge

Negative feedback with Inhibin to regulate FSH release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What does LH stimulate in the female and what is its feedback loop?

A

Development of corpus luteum -> produces progesterone -> negative feedback regulates tonic release of LH and supports corpus luteum until PGF causes regression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

The medulla of the ovary contains?

A

Vasculature, nerves, and CT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

The Cortes of the ovary contains ?

A

Oocytes and follicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Describe follicular development in the ovary.

A

Primordial follicle- oocyte surrounded by single layer of squamous cells
Primary follicle -single layer of cuboidal cells
Secondary follicle- oocyte with two or more layers and zona pellucida
Antral follicle -fluid in cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is a committed follicle?

A

Commences development from resting pool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is follicular development that is independent of FSH or LH?

A

Gonadotropin-independent growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

At what stage does a follicle become Gn-responsive?

A

Secondary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

At what stage does a follicle become Gn-dependent?

A

Antral/ Graafian

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What cells can be seen in an antral follicle?

A

Theca externa- CT
Theca interna - produce androgens under LH stimulation
Granulosa -produce estrogen, inhibin, and follicular fluid
->Columbus oophorus
-> corona radiata
-> zona pellucida

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What structure is left in the ovary immediately after ovulation?

A

Corpus hemorrhagicum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Theca interna and granulosa cells proliferate to filled the _____________ ___________ and differentiate to produce luteal cells

A

Corpus luteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Large luteal cells secrete?

A

Progesterone, oxytocin, and relaxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

In the tonic GnRH center, GnRH release is controlled by?

A

Pulse generator

-internal and external signals

49
Q

In the surge center, GnRH release is stimulated by?

A

Follicular wave of estrogen and prostaglandin production in endometrium

50
Q

Release of GnRH from the surge center causes an LH surge that is required for?

A

Ovulation

51
Q

What is the function of estrogen?

A
Thicken vaginal mucosa
Mucus secretion 
Mitosis of endometrium 
Increased ciliary beat in tubual cels 
Increased endometrial edema 
Myometral activity 
Estrous behavior
52
Q

Progesterone released from corpus luteum does?

A

Increase endometrial secretion
Reduce myometrial activity
Prime brain to enhance effect of estrogen

53
Q

What hormone controls leuteolysis?

A

PGF 2a from endometrium
Ipsilateral in ruminants
Systemic in mare

54
Q

Describe the control of luteolysis ?

A

Progesterone from CL induces PGF release from endometrium

PGF delivered to ovary (PGF into uterine vein, through countercurrent exchange moves into uterine artery ->ovarian artery) -» lysis of CL

In pregnancy- embryo produces signals to inhibit PGF production and maintains CL

55
Q

Breeding seasonality is mediated by?

A

Photoperiod

Reinstalled-> produce melatonin in pineal gland during hours of darkness

56
Q

How does the effect of melatonin differ between short day and long day breeders?

A

Short day- melatonin increase GnRH release (small ruminants)

Long day- melatonin decrease GnRH release (horse)

57
Q

What is the difference between puberty and sexual maturity?

A

Puberty- production of gametes

Sexual maturity-adequate size for pregnancy, delivery, and lactation

58
Q

where do GnRh neurons originate?

A

Olfactory placode

Migrate through the forebrain to the hypothalamus

59
Q

What has a negative effect on prepubertal GnRH pulsatility?

A

GABA, Neuropeptide Y (NPY)

60
Q

What has a positive effect on prepubertal GnRH Pulsatility?

A

Kisspeptin
Most likely mediator of pulsatilty

Not known how kisspeptin plays a role in onset of puberty

61
Q

What is Leptin? What does it mediate?

A

Adipocyte hormone

Infusion of Lenin can precipitate puberty- sense adequate body size and maturity

62
Q

Preovulatory GnRH surge is due to positive feedback of __________

A

Estradiol

63
Q

Prepubertal, how does estradiol feedback on the hypothalamus?

A

Follicular development -> low amounts of estradiol -> negatively feedback on hypothalamus -> decrease GnRH release -> lower LH -> follicles do not develop and no ovulation

64
Q

Hypothalamic sensitivity to estradiol changes at ______________ and permits development of?

A

Puberty

Larger follicles and ovulatory GnRH (LH) surge

65
Q

Estrous cycle

A

Period from the beginning of one estrus to the beginning of the next

66
Q

What are the three phases of estrus?

A

Follicular phase-proliferative
Luteal phase- secretory
Quinescent-anestrus

67
Q

What hormones are involved in spontaneous ovulation?

A

GnRH -> LH -> estradiol positive feedback -> GnRH and LH surge-> ovulation

68
Q

What is the pathway for induced ovulation

A

Sensory neurons from uterus to surge center ->GnRH release-> LH surge -> ovulation

69
Q

What are the types of cyclicity?

A

Polyestrus -cow/pig

Seasonal polyestrus- goat/horse

70
Q

What are the characteristics of a non-seasonal polyestrus cycle of cattle?

A

18-24days
Proestrus/ estrus/ metestrus/ diestrus
Ovulation 10-15hrs after end of estrus

71
Q

What are signs of estrus in the cow?

A
Standing to be mounted 
Secondary signs
-mounting,sniffing
-increased activity 
-decreased milk yield 
-clear vaginal mucus
-bellowing 
-swollen vulva
72
Q

What is the breeding season of the ewe?

A

Seasonally polyestrus
Short day breeds
First ovulation often unaccompanied by signs of estrus (silent ovulation)

73
Q

The estrous cycle of an ewe is _________ days, estrus lasts for _____ hours, and ovulation is usually _____________ hours after beginning of estrus

A

13-19 days
36hours
20-30hrs

Diestrus 14-15days- leuteolysis if no embryo present after 12 days

74
Q

Diestrus

A

Corpus luteum present and high progesterone

75
Q

Signs of estrus in ewe

A

Seek out ram
Vulvar edema
Ram with marking harness

76
Q

What kind of estrus cycle does a doe have? How long is the cycle?

A

Seasonally polyestrus- short day breeder

18-24days

77
Q

Detection of estrus in a doe?

A
Swollen vulva
Rapid side-to-side tail movement 
Restlessness 
Increased focalization 
Teaser buck 
Vaginal mucus
78
Q

Puberty in the sow is induced by?

A

Stress
Boar effect
Hormones

(Around 6months)

79
Q

What type of estrus cycle to sows have?

A

Polyestrus, nonseasonal

Cycle around 21 days

80
Q

What type of estrus cycle does the mare

A

Seasonally polyestrus-long day breeders

81
Q

The cycle of the mare is _______ days long and estrus lasts _______ days.

A

15-26days

5-7days (longer is early season but short in peak season)

82
Q

Dogs reach puberty around _________ months

A

6-12

83
Q

What type of cycle does the dog have?

A

Monestrous, non-seasonal

About 6months cycle

84
Q

How is the estrous cycle monitored in the dog?

A

Vaginal cytology
Progesterone
LH

85
Q

What type of cycle does the cat have?

A

Seasonally polyestuous

Induced ovulatory

86
Q

Detection of estrus in cats?

A

Rubbing against people/inanimate objects
Vocalizing
Posturing

87
Q

Ages of puberty

A
Sow 6months
Doe 6-8 months 
Cat 6-10 months 
Dog 6-12 months
Mare 8-15months 
Camelid 5months-2yrs
88
Q

What is the estrus cycle in camelids?

A

Nonseasonal, polyestrus

Induced ovulatory

89
Q

Detection of estrus in camelids

A

Behavior response to male -Crush and allow mounting

Tone and edema of uterus

90
Q

What is the follicular phase of the ovarian cycle?

A

Proestrus and estrus
Developing follicles
Estrogen-dominated

91
Q

What is the luteal phase of ovarian cycle?

A

Ovulation to CL regression

Progesterone dominated

92
Q

What is the blood supply to the scrotum?

A

External pudendal artery

93
Q

What nerves innervate the scrotum?

A

Genitofemoral nerve

94
Q

What is the lymph drainage of the scrotum?

A

Superficial inguinal lymph node

95
Q

How is temperature maintained in the testicles?

A

4 degrees lower than core body temp

Pampiniform plexus: countercurrent exchange
Scrotal skin: thin with numberous sweat glands
Cremaster: raise and lower
Whole body response: increase temp->increased respiratory rate

96
Q

What is the function of the pampiniform plexus?

A

Thermoregulation: countercurrent
Testosterone concentration: countercurrent
Reduced pulsatility: contorted and long

97
Q

What is the function of the blood-testis barrier?

A

Maintain unique environment for development and maturation of germ cells
Protect germ cells for noxious agents
Prevents autoimmune response to sperm

98
Q

What is the function of the epidiymis?

A

Sperm maturation, storage, and transit

All epididymal functions are androgen dependent

99
Q

What are the two types of penises?

A

Musculocavernosus- stallion, dog, cat

Fibrous- ruminants, boar, camelids

100
Q

The ____________ nerve is responsible for sensory innervation of glans penis (essential for ejaculation)

A

Dorsal

101
Q

Anti-Mullerian hormone does what?

A

Inhibits paramesonephric duct development in embryo

Low levels in postnatal male- elevated in chryptorchid

102
Q

In the male, LH acts primarily on _________ cells to stimulate the production of ___________

A

Leydig; testosterone

103
Q

Prolactin is secreted by? And has what function?

A

Prolactin is secreted by the pituitary gland and enhances LH-induced testosterone secretion

104
Q

FSH acts on Sertoli cells to promote synthesis of what 4 proteins?

A
  1. Androgen binding protein (ABP)- concentrate testosterone in epididymis.
  2. Inhibin - negative feedback effect on pituitary for FSH
  3. Estrogens
  4. Testosterone to dihydrotestosterone
105
Q

What is the function of testosterone?

A

Spermtogenesis

Countercurrent exchange concentrates hormone levels in testes in addition to ABP

106
Q

What is more potent than testosterone as a mediator of sexual development and secondary sex characteristics

A

Dihydrotestosterone

107
Q

Estrogen is produced by what cells in the male and has what function?

A

Sertoli cells
Support spermatogenesis
Negative feedback to hypothalamus

108
Q

What is the function of inhibin in the male?

A

Produced by Sertoli cells

Negatively feeds back to pituitary to decrease FSH

109
Q

Seasonality of GnRH release in males is regulated by?

A

Photoperiod on pineal gland and production of melatonin

110
Q

What is the process of spermatogenesis?

A

Spermatogenesis -> spermatocyte (via mitosis)
Primary spermatocyte -> secondary spermatocyte
(Via meiosis I)
Secondary spermatocyte -> spermatids (via meosis II)
Spermatic -> spermatozoa (morphological changes)

111
Q

What is the difference between spermtocytogenesis and spermiogenesis ?

A

Spermacytogenesis - formation of spermatid from spermatogonia

Spermiogenesis - morphological change of spermatid to spermatozoa

112
Q

What occurs on the epididymis?

A

Sperm acquire capability for motility and fertilization

Stored in tail

113
Q

Libido is determined by

A

Genetics

Threshold level of testosterone

114
Q

What structures are required for erection in ruminants?

A

Corpus cavernosum
Corpus spongiousm
Ischiocavernosus muscle (pudendal nerve)

115
Q

Emission vs ejaculation

A
Emission = ejection of sperm from epididymis 
Ejaculation= ejection of semen from urethra
116
Q

What nerves are required for ejaculation ?

A

Affterent- pudendal nerve to spinal cord

Efferent

  • hypograstric to muscles
  • neuroendocrine loop with oxytocin
117
Q

Seminal fluid is produced by?

A

Accessory sex glands- ampulla, vesicular glands, prostate, bulbourethral

118
Q

What is present in seminal fluid and what is its function ?

A

Prostaglandins, citrate, fructose, zinc, mucus

Sperm motility, metabolism, uterine contraction, DNA stabilization, Capacitation, immunoregulation

B-nerve growth factor (ovulation inducing factor)

119
Q

Copulation

A

Visual stimuli
Penile sensation
Musculoskeletal system
Initiate ejaculation