Repro 2 Flashcards
1
Q
Do dogs and cats have seminal vesicles?
A
NO!
2
Q
T/F: The size of the testes is generally not related to the size of the animal
A
True
3
Q
Types of testicular cells
A
- somatic cells
- germ cells
4
Q
Interstitium (Inter-tubular) cells
A
- Leydig cells
- mast cells
- CT
- blood and lymph vessels
5
Q
Seminiferous tubule (intra-tubular) cells
A
- peritubular cells
- Sertoli cells
- germ cells
6
Q
The Leydig cell is the site of _________ in the testis
A
androgen biosynthesis
7
Q
These cells are also called supporting cells or the nurse cells
A
Sertoli cells
8
Q
Sertoli cells have a ____ population in the seminiferous tubules - they stop dividing in early neonatal peroid
A
fixed
9
Q
Tight junctions or the zonula occludens between adjacent Sertoli cells constitute the __________
A
blood-testis barrier
10
Q
The blood-testis barrier divides the seminiferous epithelium into ______ and ________ compartments
A
basal and adluminal
11
Q
The basal compartment has germ cells in ____
A
mitosis
12
Q
The adluminal compartment has germ cells in ______
A
meiosis
13
Q
During mitosis and meiosis in the testis, the dividing cells are connected by cytoplasmic bridges. Why?
A
Allows cells in the same cohort to communicate w/ each other and maintain synchrony of differentiation
14
Q
What is spermiation?
A
process by which mature spermatids are released from Sertoli cells into the seminiferous tubule lumen prior to their passage to the epididymis
15
Q
Residual bodies released from the sperm are phagocytosed by ___________
A
Sertoli cells
16
Q
The sperm head consists of ….
A
nucleus and acrosome
17
Q
The sperm tail consists of ….
A
- connecting piece or neck
- middle piece
- principle piece
- end piece
18
Q
What is the arrangement of microtubules inside the tail of the sperm?
A
9 + 2 arrangement
9 doublets in a ring with one doublet in the center
19
Q
T/F: Type A1 cells in the testis can revert to Type A0.
A
True
It reverts back to a stem cell for sperm production
20
Q
What is spermatogenesis?
A
process in which spermatozoa are produced from male primordial germ cells by way of mitosis and meiosis
21
Q
T/F: Waves of spermatogenesis is a concept in SPACE and the seminiferous epithelial cycle is a concept of TIME.
A
TRUE!
Note: this is often a T/F question on the test!!!!!!!!
22
Q
T/F: The duration of spermatogenesis can not be altered by hormonal treatment, changes in temperature, etc.
A
True
23
Q
T/F: The duration of spermatogenesis can be easily calculated
A
true
24
Q
How is the duration of spermatogenesis calculated?
A
number of SE cycles x duration of one SE cycle
SE cycle = seminiferous epithelial cycle
25
What is the importance of cytoplasmic bridges present between developing male germ cells?
To maintain synchrony of differentiation
26
Factors regulating daily sperm production (4)
- spermatogonial divisions
- seasonal variations (environment)
- cellular degeneration
- hormones
27
_____________ determine the quantitative yield of sperm.
Spermatogonial divisions
28
Mitotic divisions controlled by ___________
germ cell/ Sertoli cell ratio
29
___________ can support only a fixed no. of germ cells
Sertoli cells
| "ceiling effect" for sperm output
30
In summer months, male animals can experience ______ sperm output and sperm motility
decreased
31
One A1 spermatogonia can result in _____ sperm
512
32
Optimal thermal environment for normal spermatogenesis is _______, which is approx. 5 degrees C below body temperature
32 degrees C
33
Scrotum (5)
- relatively thin skin
- sweat glands and sebaceous glands
- lack of subcutaneous layer of fat in the scrotal fascia
- fibromuscular layer in the skin = Tunica Dartos
- intracapsular position of large testicular blood vessels
34
Regulation of testicular temperature is accomplished by...
scrotum and pampiniform plexus
35
What fibromuscular lauer in the skin of the scrotum is sensitive to temperature changes?
tunica dartos
36
Describe the pampiniform plexus in the spermatic cord
The outer membrane of the testicular artery merges with the outer membrane of the testicular vein.
Inflowing arterial blood exchanges heat with outflowing venous blood.
37
Androgens (4)
- support spematogenesis (maintaienance)
- induce and maintain differentiation of male internal and external reproductive organs
- induce secondary male sex characteristics
- influence sexual behavior
38
In addition to functions, what do androgens promote? (3)
- protein anabolism
- somatic growth
- regulate secretion of gonadotropins
39
Functions of FSH in males
- synthesis of ABP, inhibin, activin, and aromatase
| - increases LH receptors on Leydig cells
40
_____ in males leads to the synthesis and secretion of testosterone
LH
41
___ acts via Sertoli cells to stimulate spermatogenesis (initiation)
FSH
42
_____ increases the number of spematogonia and spermatocytes
FSH
43
________ regulates meiosis till pachytene stage
FSH
44
___ regulates Leydig cell numbers through androgen receptors in interstitial cells
FSH
45
_____ is necessary for the initiation of spermatogenesis, while _____ is necessary for the maintainance of spermatogenesis.
FSH; Testosterone
46
______ and __________ reduce FSH secretion
Inhibin and follistatin
47
_________ increases FSH secretion
Activin
48
Epithelium of the epididymis?
pseudostratified
49
The duct of the epididymis is lined by _________ muscle to facilitate sperm movement
smooth
50
There are three kinds of cells in the epithelium of the epididymis. What are they/
- basal
- principal
- clear
51
What do basal cells do?
regenerate epithelium
52
What do principal cells do?
absorb fluid and secrete substances such as alpha glycerophosphorylcholine, sialic acid, and carnitine
53
The blood-epididymis barrier is formed by _______ junctions between principal cells and creates an anatomical, physiological, and immunological barrier.
tight
54
What do clear cells do?
phagocytose cytoplasmic droplets
55
Fluid within the epididymis duct has _______ to keep the spermatozoa quiscent
low oxygen tension
56
T/F: Spermatozoa lack cytoplasm and organelles to perform normal cell functions
True
57
Under anaerobic conditions, sperm utilize _________ that is present in abundance in the seminal plasma
fructose
58
Functions of the epididymis
- maturation of spermatozoa
| - storage of spermatozoa
59
T/F: Spermatozoa released from the seminiferous epithelium are fully mobile.
FALSE!!
They are immotile!!
60
Where do spermatozoa acquire their motility?
in the epididymis
61
T/F: The region of the epididymis where spermatozoa gain their fertilizing ability is species-specific.
True
62
The major site for storage of spermatozoa is the ________
cauda epididymidis
63
Smooth muscle fibers in the terminal part of cauda epididymidis and vas deferens contract __________
only during ejaculation
64
How long can spermatozoa stored in the cauda retain fertilizing capacity?
several weeks
65
On average, spermatozoa are transported through the epididymis in _______ (species dependent)
7 to 16 days
66
Does increasing the frequency of ejaculation change the transit time through the epididymis?
Yes, it can reduce transit time by 10-20%. However the sperm may not have fully matured though
67
This fibromuscular duct begins at the tail of the epididymis
ductus deferens
68
In the ductus deferens, sperm are stored in the _________ portion and _________ movements propel the sperm
proximal; peristaltic
69
Male Accessory Sex Glands
- pair of ampulla (ductus deferens)
- seminal vesicles
- prostate gland
- bulbourethral glands (Cowper's glands)
- urethral glands
- preputial glands = modified sebaceous glands seen in rodents
70
Seminal plasma, or accessoty gland secretions, are mixed with sperm and fluid from the cauda epididymis to form _____ at the time of ejaculation
semen
71
Semen, the mixture of sperm and seminal plasma, contains what other things to help the sperm survive? (6)
- electrolytes
- fructose = energy source
- ascorbic acid
- vitamins
- proteases
- prostaglandins
72
Main function of the seminal plasma?
- provide an environment conducive to sperm survival within the female repro tract
- prevent immunologic response in the female
73
What might be the reason that there is a 1000-fold difference in the amount of citric acid in the seminal plasma than in the blood plasma?
may be involved in maintaining pH in the male and female tracts (vagina is acidic)
74
What do the prostaglandins in the seminal plasma do in the female repro tract?
- cause changes in cervical mucus
| - cause uterine contractions to aid sperm transport
75
Function of cholesterol and lipids in seminal plasma?
may help keep sperm quiscent until deposited into the female tract
76
Why is there zinc in the seminal plasma?
inhibits sperm activation
77
In which species does the male have penile spines on his caudally facing glans penis?
cat
78
Two types of phallus
- fibroelastic phallus
| - musculocavernous/ vascular phallus
79
The features of this phallus include:
- small blood spaces
- substantial amounts of fibroelastic tissue
- sigmoid flexure
- rapid erection
fibroelastic phallus
80
What species are examples of fibroelastic phallus?
- ruminants
| - swine
81
What species are examples of musculocavernous phallus?
- stallion
| - man
82
The features of this phallus include:
- large blood spaces
- less fibroelastic tissue
- slow erection
musculocavernous
83
What causes the erection of the penis?
highly coiled arteries in the cavernous bodies that uncoil
This uncoiling allows rapid passage of large volumes of blood to fill and distend the sinuses
84
Transport of sperm from cauda epididymidis to the female reproductive tract requires _________ and ___________
erection and ejaculation
85
There are two stages to ejaculation. What are they?
- emission
| - ejaculation
86
Function of testis and seminiferous tubules?
sperm production
87
Function of collecting ducts?
transport and storage
88
Function of epididymis?
transport, maturation, and ejaculation
89
Function of vas deferens?
transport and ejaculation
90
Function of seminal vesicles?
secrete thick liquid to transport sperm
91
Function of prostate gland?
secretes thin alkaline solution to neutralise urine and female system
92
Function of bulbourethral gland?
secretions may lubricate, flush out urine, or form a gelatinous plug
93
In ejaculation, what happens during the emission stage?
sperm move from the cauda epididymidis and vas deferens into posterior urethra
94
Emission is under what type of nervous regulation?
sympathetic autonomic
95
This is the forceful expulsion of the semen from the penile urethra
ejaculation
96
What is the function of penile papillae?
stimulate vagina
97
Which hormone is necessary for the maintenance of penile papillae?
DHT
98
____________ is necessary for accessory sex glands, while ____________ is essential for external genitalia
Testosterone; DHT
99
Fertilization occurs in the ________ region of the oviduct
ampulla
100
T/F: Oocytes live longer than spermatozoa.
FALSE!!!
| Spermatozoa live longer than oocytes
101
These structures of the oviducts contract and direct the ovum into the funnel-shaped opening of the oviducts
fimbriae
102
Primary barries for sperm to reach ampulla from uterus/ vagina
- mucus secreted by cervix
- peristaltic muscle contractions in the oviducts are directed towards the uterus to transport ovum
- transport of oviductal fluid by cilia towards uterus -against the direction which sperm need to go
103
Transport of sperm in the female reproductive tract occurs in these two phase
rapid phase and slow phase
104
General summary of the rapid phase
sperm (dead/alive) arrive at the site of fertilization within 2-10 minutes
105
What is responsible for the rapid phase/
- myometrial contractions initiated by oxytocin
| - prostaglandins in the semen
106
Why is there oxytocin for the myometrial contractions of the rapid phase?
Female secretes it as a result of coitus
107
Spermatozoa that arrive within a few minutes after mating _____ fertilize the ovum
DO NOT
108
Describe slow phase
- Sperm reside for several hours in the cervical crypts, endometrial glands, and crypts in the uterotubal junctions following depostion
- During this time, sperm undergo capacitation
109
During capacitation: (3)
- cholesterol coat is removed
- channels are established in the acrocome
- loss of ions such as zinc, calcium, magnesium, and sodium
110
What permits the activation of acrosome?
removal of the cholesterol coat from the sperm surface
111
What is essential for sperm penetration?
Channels in the acrosome that allow the release of pro-acrosin and hylauronidase
112
Sperm acquire __________ when they come in contact with secretions from seminal vesicles
Glycodelin-S
113
During slow migration in the female repro tract, sperm exchange Glycodelin-S with ________
Glycodelin-A and-F
| secreted by estrogen-primed uterus and fallopian tube
114
Function of Glycodelin-A and -F?
bound to head region of sperm to prevent premature sperm acrosome reaction
115
After capacitation, there are 3 more steps in the slow phase. What are they/
- changes in sperm cell surface proteins = Glycodelin-S to Glycodelin-A and -F
- activation of ion channels on sperm surface
- aquire motility
116
Why is it essential for the activation of ion channels on sperm surface to occur?
change in pH from acidic to neutral as sperm migrate from cervix to uterus and fallopian tube
117
____________ is essential for the successful transport of sperm
estrogen-primed uterus
118
What 2 things allow for sperm transport in the slow phase?
- uterine contrations
| - motility of sperm acquired during the process of activation in the female tract
119
T/F: The majority of sperm will reach the site of fertilization
FALSE!!
Majority WILL NOT!
120
which chemical of uterine origin initiates lutelysis in most species?
PGF2-alpha
121
In cows, ovulation occurs in _______ phase of the estrous cycle.
metestrus
