Unit 7 - Reproductive System Flashcards
1
Q
Which reproductive system is more complex, the female or the male?
A
female
2
Q
What are the functions of the female reproductive system? (7)
A
- production of hormones
- develop gametes
- receive male gametes
- furnishes a site for gametes to fertilize the ovum
- provides environment for embryo to grow and develop
- carries embryo for entire pregnancy
- pushes offspring out when fully developed
3
Q
where is the reproductive tract located in the female repro system?
A
pelvic cavity, positioned along rectum in mammalian farm animal prod species
4
Q
What are the 7 parts of the female repro system?
A
- broad ligaments
- ovaries
- oviducts
- uterus
- cervix
- vagina
- vulva
5
Q
What are the broad ligaments?
A
a suspensory tissue that supports the ovaries, oviduct, uterus, cervix, and the anterior vagina
contains blood vessels and nerve fibers that supply the ovaries, oviducts and uterus
6
Q
What are the three segments of the broad ligaments
A
- mesometrium: support the uterus
- mesosalpinx: supports the oviducts
- mesovarium: supports the mesovarium
7
Q
What are two features of the ovaries?
A
- primary organs of reproduction of a female
- has both endocrine and cytogenic functions
8
Q
What are the two functions of the ovaries?
A
- produce hormones, which are released directly into the blood stream
- produce the ova (female gametes) which are released from the surface of the ovary during ovulation
9
Q
What are the categories of hormones produced in the ovaries?
A
estrogens
progestins
10
Q
Where are estrogens produced in the ovaries?
A
produced by cells of the developing ovarian follicles
11
Q
What are the functions of estrogens?
A
responsible for physical and behavioural activity that prepare for breeding and pregnancy
mounting, phonation, willingness to be mounted by other animals
12
Q
Where are progestins produced in the ovaries?
A
produced by the corpus luteum that develops from the empty follicle after ovulation
13
Q
What are the functions of progestins?
A
help prepare the uterus for implantation of a fertilized ovum
necessary for pregnancy to be maintained once implantation occurs
14
Q
What are the parts of the ovary?
A
- tunica albuginea
- ovarian stroma
- ovarian medulla
- ovarian cortex
- follicles
- primordial follicles
- primary follicle
- secondary follicle
- tertiary follicle
15
Q
What are some features of the tunica albuginea?
A
covers the surface of the ovary
formed by connective tissue
16
Q
What are some features of the ovarian stroma?
A
surrounds the follicles
formed by loose connective tissue
composed of the ovarian cortex and the ovarian medulla
17
Q
What is the ovarian cortex?
A
outer region where the follicles rest, develop, and mature
18
Q
What is the ovarian medulla?
A
middle part of the ovary, contain blood vessels, lymph vessels and nerve fibers
19
Q
What is superovulation?
A
Superovulation (SOV) is a necessary technique to produce large numbers of embryos for embryo transfer
20
Q
What is the difference in the ovarian stroma in horses?
A
ovarian cortex is in the middle and the medulla is on the outside
21
Q
What is the primordial follicle?
A
- is a combination of a primary oocyte and a surrounding layer of flattened epithelial (follicular) cells
- at birth, the ovaries of most domestic species contain hundreds to thousands of primary follicles waiting to continue their development
- dormant follicles with a single layer of follicular cells clustered together at the periphery of the ovary
22
Q
What is FSH?
A
Follicular stimulate hormone
23
Q
What is FSH function?
A
following puberty, the primary oocyte surrounded by follicular cells enters follicular maturation when stimulated by FSH
primordial cells become primary cells
24
Q
Does our number of primordial follicles increase?
A
no, you are born with a certain number of primordial follicles and you lose them overtime
25
What is a primary follicle?
- still contains the primary oocyte
- squamous epithelium becomes cuboidal epithelium, which keeps proliferating as the follicles develops
26
What do granulosa cells secrete in the primary follicle?
glycoproteins that cross-link to form a protective shell, known as zona pellucida around the oocyte
27
What is a secondary follicle?
- comprises of primary oocyte surrounded zona pellucida and multiple layers of cuboidal follicular cells now called granulosa cells
- oocyte is enlarged and surrounded by granulosa
28
What can you see at the late secondary follicular stage?
- theca, consisting of layers of cells immediately surrounding the granulosa
- internal layer produces hormones and serves as substrates for estrogen production
- external layer is formed by fibroblasts and smooth muscle like cells
- accumulation of cellular secretions among the granulosa cells which forms a fluid filled cavity known as antrum
29
What is the antrum?
fluid filled cavity found in a late secondary follicle
30
What is a tertiary follicle?
- large preovulatory follicles which bulge from the surface of the ovary
- final stage of follicular development and contain a well-defined follicular antrum
- oocyte sits on cumulus oophorus
- zona pellucida is surrounded by corona radiata
31
what is the mound of granulosa cells that the oocyte sits on top of in a tertiary follicle?
cumulus oophorus
32
What is the corona radiata?
thin layer of granulosa cells that surrounds the zona pellucida of a tertiary follicle
33
What happens during the ovulation?
- the surface of the mature follicle weakens and physically ruptures the fluid from the antrum
- the rush of fluid out of the follicle carries the ovum with it, still surrounded by the corona radiata
- the follicle ruptures, collapses and shrinks
- there is unfolding of the follicular wall forming the corpus hemorrhagicum with accumulation of blood into the antrum
34
What happens to the corpus luteum if fertilization occurs or if it doesn't occur?
- corpus luteum has a limited lifespam
if fertilization occurs
- will be maintained
if fertilization doesn't take place
- degenerate and be replaced by fibrous connective tissue forming the corpus albican
35
What are the oviducts?
also known as the fallopian tubes or the uterine tubes
- convoluted tubes that extend from the tips of the uterine horns
36
What is the function of the oviducts?
guide the oocyte from the ovary to the uterus and to serve as a site for fertilization of ova by spermatozoa
37
What are the parts of the oviducts?
- infundibulum: wide distal portion of the uterine tube
- ampulla: wider lateral 2/3 of the uterine tube
- isthmus: is the narrower medial 1/3 of the uterine tube
- uterine part: is the intramural segment of the uterine tube located within the wall of the uterus
38
What is the fimbriae?
muscular, finger-like projections in the infundibulum of the oviducts
- they touch the surface of the ovary and position the infundibulum where the follicles are locates, this helps ensure that the infundibulum is properly positioned to catch the ova when ovulation occurs
39
Are the uterine tubes attached to the ovaries?
no
40
When ovulation takes place, where are the ova caught?
by the funnel-like infundibulum, which is the enlarged opening at the end of each oviduct
41
What are some features of the uterine tube?
- walls lined with smooth muscle and cilia
- used to guide fertilized oocyte (zygote) to the uterus
- delicate muscle contractions and gentle movements of cilia to help the ova to move to the site of fertilization
42
What is the ampulla?
upper portion of the oviduct (uterine tube) closest to the ovary
it is wider than the isthmus and is the site of fertilization
43
What is the isthmus?
final segment of the uterine tube that connects it to the uterine horns
44
What is the UTJ?
(Utero Tubal Junction)
narrow passage that connects the uterus to the uterine horn to the uterine tube
it is a site that will contribute to a selection process of the sperm that will move into the isthmus and ampulla
45
Where does the mammalian sperm form a reservoir in the uterine tubes?
after passing the UTJ, the sperm forms a reservoir by binding the epithelium of the isthmus
46
What does the reservoir of the sperm in the isthmus do?
increases the odds of fertilization when there is asynchrony between mating and ovulation, in pigs and cattle, sperm are stored for 24-48 hours
47
Where does the oocyte go to after it is discharged by the ovary?
ideally be caught by the infundibulum in the uterine tube, oocyte then gets fertilized by a spermatozoa, fertilized oocyte will eventually migrate to uterine horn, divides through various stages in its transformation where the embryo will further develop, implants in the endometrium (uterus)
48
How is the uterus formed?
- series of tubular structures, the cervix (it opens causally to the vagina)
- the uterine body (in the middle part)
the uterine horns (they communicate proximally with the oviducts)
49
What is the uterine body the site for?
where semen is deposited during AI
50
After fertilization, where does the fertilized egg implant?
the fertilized egg implants in one of the uterine horns and allows the embryo to grow
51
How does the uterine body change throughout pregnancy?
expands and adapts to fetal growth, reaching a large size, it will grow along with the developing offspring and then return to its original size after birth
52
What are the three layers of the uterus?
- perimetrium: outer layer
- myometrium: muscular layer
- endometrium: innermost layer
53
What is the placenta?
- organ that develops in the uterus during pregnancy
- multilayered, fluid-filled membranous sac that develops around the embryo
54
What is the amnion?
part of the placenta, it is the layer immediately around the fetus, forming the amniotic cavity
55
What is the amniotic fluid?
inside the amniotic cavity, protects the fetus, and allows its movements
56
What is the allantois?
part of the placenta, it is the layer surrounding the amniotic sac, it forms the allantoic cavity
57
What is the function of the allantois?
enables vascular communication between the developing embryo and its mother
58
What is the chorion?
part of the placenta, a membrane placed outside the allantoic sac, which attaches to the uterine lining, the attachment of the chorion to the uterus is the site that maternal and fetal blood vessels intertwine with each other, this facilitates exchange of nutrients and waste products
59
What is the attachment of the chorion to the uterus called?
chorion-endometrial junction
60
What is a characteristic of the circulation in the chorion and the endometrium?
fetal circulation in the chorion is close to the maternal circulation in the endometrium, it allows oxygen and nutrients to pass from maternal blood to fetal blood and waste products can pass from the fetal blood to the maternal blood
61
Where is fetal vs maternal circulation located?
fetal circulation is located in the chorion (membrane on the placenta which attaches the uterine lining)
maternal circulation is located in the endometrium at the chorion-endometrial junction
62
What are the four variations of chorion attachment to the uterus?
diffuse
cotyledonary
zonary
discoid
63
What are some features of diffuse chorion attachment?
- have a uniform distribution of chorionic villi covering the chorions surface
- attachment sites between chorion and uteris are spread out over the whole surface of placenta and whole surface of uterus
- enables placenta to easily detach from uterus after delivery and be expelled from the dam
64
What are some features of the cotyledonary attachment?
- multiple area of attachment called cotyledons are formed by interaction of patches of placenta with endometrium
- the fetal portions of this type of placenta are called cotyledones, the maternal sites are called caruncles and the cotyledon-caruncle complex is called a placentome
65
What are caruncles?
round thickenings in the uterine mucosa resulting from proliferation of subepithelial connective tissue
- they are the only site int eh uterus to form attachments with fetal membranes
66
What are some features of the discoidal attachment?
- a single placenta is formed and is discoid in shape
- seen in primates, rodents and humans
67
What are some features of the zonary attachment?
- forms a complete or incomplete band of tissue surrounding the fetus
- seen in dogs, and cats
68
Where is the cervix located?
smooth muscle sphincter located between the body of the uterus and the vagina
backwards it protrudes into the vagina and forms a blind-ended pocket called the cervical fornix that surrounds the cervical opening
69
What is the cervix's normal state?
cervix is normally tightly closed except at estrus (heat) and parturition (birth)
70
Why does the cervis relax at estrus?
the cervis relaxes at estrus to admit spermatozoa during breeding, and then closes during pregnancy
71
What do uterine contractions during the first stage of labor do?
they push the newborn against the relaxes cervix and gradually pry it open
72
Where is the vagina located?
between the cervix on the cranial end and the vulva on the caudal end
73
What is the vagina?
muscular tube that receives the penis at breeding time and acts as the birth canal at parturition
74
What are the two parts of the vagina?
anterior vagina - closer to the cervix
posterior vagina - closer to the vulva
75
What is the vulva?
- only portion of the female reproductive system that is visible from the outside
76
What are the main parts of the vulva?
- vestibule
- clitoris
- labia
77
What is the vestibule?
part of the vulva, it is the entrance to the vagina from the outside
- short space between labia and opening of the vagina
- urethra opens on the floor of the vestibule
78
What is the clitoris?
part of the vulva, is located on the floor of the vestibule a little nearer to the exterior than the urethral opening
79
What is the labia?
part of the vulva, also called the lips, form the external boundary of the vulva
80
What do the organs and glands of the male reproductive tract do?
manufacture the male gamete
deliver to the female reproductive tract
81
What does the male reproductive system consist of?
- two testicles in the scrotum
- urinary bladder
- ductus deferens
- ampulla (absent in male pigs)
- vesicular gland
- prostate
- bulbourethral gland
- sigmoid flexure
- penis
82
Where are the pigs testicles located?
caudal to the sigmoid flexure of the penis, just ventral to the anus
83
Do the testicles vary?
in shape, size and location
84
Where are the horses testicles located?
the long axis of each testis is nearly horizontal, and the testes are held close to the abdominal wall
85
Where are the ruminants testicles located?
near the sigmoid flexure of the penis, the long axis of each testis is nearly verticle, so the scrotum is dorsoventrally elongate and pendulous
86
What does the spermatic cord do?
part of the testicles, contains blood vessels, nerves, lymphatics and the ductus deferens, suspends each individual testis within the scrotum
87
What does each testis consist of?
mass of coiled seminiferous tubules surrounded by a heavy fibrous capsule called the tunica albuginea
88
What are septa?
part of the testicles, fibrous, pass inward from the tunica albuginea, which divide the testis into lobules
- provide a framework for support of the seminiferous tubules and the interstitial tissue
89
What is spermatogenesis?
formation of spermatazoa
90
Where does spermatogenesis take place?
seminiferous tubules
91
Where do the seminiferous tubules deliver sperm to?
network of tubules called rete testis, which drains into the efferent ductules
92
Where are the interstitial cells (leydig) located? (male repro)
connective tissue between the seminiferous tubules
93
What do the interstitial cells of the male repo system secrete?
testosterone when stimulated by the luteinizing hormone (LH)
94
Where are the sustentacular cells located?
within the seiminiferous tubules
95
What is the function of sustentacular cells?
envelop developing spermatozoa and their precursors, they nourish the developing sperm and mediate the effects of hormones on the germ cells
96
What is the epididymis?
composed of the long, convoluted epididymal duct that connects the efferent ductules of the testis with the ductus deferens, it houses the spermatozoa as they mature before they are expelled by ejaculation
97
What are the different components of the epididymis?
tail: attached by ligaments directly to the testis and to the adjacent tunica albuginea
body: lying on the long axis of the testis
head: into which the efferent ductules empty
98
What occurs to the spermatozoa after production?
they are immature and must undergo a period of maturation - usually 10-15 days
this maturation process occurs within the epididymis before they are capable of fertilization
99
What does the ductus deferens do?
muscular tube that undergoes peristaltic contractions during ejaculation, propels the spermatozoa from the epididymis to the urethra
100
What is the pathway through the testicles of the spermatozoa?
produced in the seminiferous tubules -> collected at the rete testis -> efferent ducts -> epididymis -> ductus deferens -> urethra
101
Do spermatozoa make up most of semen?
no, they only make up a small portion of semen
102
What manufactures seminal fluid to carry the spermatozoa?
- seminal vesicles
- prostate gland
- bulbourethral gland
103
Is seminal fluid acidic or alkaline?
alkaline to combat the acidity in the female reproductive tract
104
What does seminal fluid contain?
- electrolytes
- fructose: energy source
- prostaglandins: may stimulate the female repro tract to help spermatozoa move up to the oviduct
105
What are the ampulla?
glandular enlargement associated with the terminal parts of the ductus deferens, glands of the ampullae empty into the ductus deferens and contribute volume to the semen
106
What are the vesicular glands?
enters urethra in the same area as ductus deferens, they contribute fluid to the semen
107
What is the prostate gland?
unpaired gland that surrounds the pelvic urethra, it produces alkaline secretion
108
What is the bulbourethral gland?
paired glands on either side of the pelvic urethra, produces the pre-ejaculate fluid that helps to neutralize the acidity of the urethra for passage of spermatozoa
109
What are the three areas of the penis?
glans: free extremity
body: main portion
root: attach to the ischial arch of the pelvis
110
What is the bulk of the penile's body internal structure composed of?
paired columns of erectile tissue called corpus cavernosum
- network of fibrous connective tissue and blood filled spaces or sinuses
111
What is the blood flow like in the non erect state of the penis?
blood flow into erectile tissue equals blood flow out of erectile tissue
112
What occurs during the erect state of the penis?
blood inflow exceeds outflow
- sinuses engorge with blood and try to enlarge
- extent of enlargement limited to a small increase due to presence of an inelastic connective tissue network
- causes of enough hydrostatic pressure to cause erectile tissue to get a lot stiffer, this is the erection of the penis
113
How does the sigmoid flexure contribute to erection?
it is an s-shape
- erection results from straightening the s shape of the non erect penis
- penis protrudes from prepuce for breeding
- retractor penis muscle pulls penis back to non-erect s shape
114
What are some features of the retractor penis muscle?
- attached to the bend of the sigmoid flexure
- when erection straightens out the sigmoid flexure, this muscle stretches
- when the erection is over, the retractor penis muscle pulls the penis bent back into an s shape
