REPRODUCTIVE SYSTEM Flashcards
The female reproductive system
Broad ligaments
ovaries
roduce hormones, which are released
directly into the blood stream
roduce the ova (female gametes) which
are released from the surface of the ovary
during ovulation
etrogens: produced by cells of the
developing ovarian follicles
Responsible for physical and behavioral activity
that prepare for breeding and pregnancy
Mounting, phonation, willingness to be
mounted by other animals
Progestins: produced by the corpus luteum that
develops from the empty follicle after ovulation
Help prepare the uterus for implantation of a
fertilized ovum
Necessary for pregnancy to be maintained once
implantation occurs
The Ovary
Parts of the ovary
Primordial Follicles / what is its functions
A primary follicle in the ovaries is simply a young egg cell (primary oocyte) wrapped in a thin layer of flat skin-like cells (follicular cells). At birth, animals have many of these primary follicles in their ovaries, all ready to grow and develop further.
primordial follicles part of there functions
Primordial follicles are sleeping egg cells in the ovary, each surrounded by a single layer of follicular cells, and they’re all gathered around the edge of the ovary, waiting to wake up and grow.
Primordial Follicles
Follicular Stimulate Hormone (FSH) what is its function
After puberty, when the Follicle Stimulating Hormone (FSH) kicks in, the primary oocyte (young egg cell) with its surrounding follicular cells begins to mature. This is the process where a primordial follicle wakes up and transforms into a primary follicle, ready to take the next steps in development.
primary follicile
As the primary follicle matures, it still holds the primary oocyte. The difference now is that the flat (squamous) skin-like cells around it turn into cube-shaped (cuboidal) cells. These cuboidal cells keep multiplying, helping the follicle to grow and develop further
Granulosa cells, which are part of the follicle surrounding the egg cell (oocyte), produce sticky proteins that link together to create a protective layer called the zona pellucida around the oocyte. This layer acts like a shield for the egg cell.
secondary foccile
A secondary follicle is a stage in the development of egg cells in the ovaries. Think of it as a little egg house that’s getting ready for a possible future pregnancy. Here’s what’s inside this “house”:
Primary Oocyte: This is the egg cell that’s not fully grown yet.
Zona Pellucida: It’s like a protective jelly coat around the egg cell, keeping it safe.
Granulosa Cells: These are helper cells that have multiplied to form many layers around the egg. They help the egg grow and produce important hormones.
Antrum: A fluid-filled space that shows the follicle is maturing.
As this “house” gets more developed, it’s preparing the egg inside for the chance to be fertilized and potentially start a pregnancy.
late secondary docile
A 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 by fibroblasts,
and smooth muscle-like cells
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late secondary foccile
At this stage we can see:
Accumulation of cellular secretions among
the granulosa cells
Forming a fluid filled cavity known as antrum
terteriariy foccile
They are big follicles ready for ovulation that stick out from the ovary’s surface.
This is the final stage of follicular development and
contain a well-defined follicular antrum
terterirairy foccile
The (oocyte) egg cell rests on a small hill of helper cells known as the cumulus oophorus, and its protective jelly layer, the zona pellucida, is encircled by a slim layer of helper cells called the corona radiata.
Follicular development
ovulation
The outer layer of the mature follicle becomes fragile and breaks open, letting the fluid inside it spill out. This burst of fluid sweeps the egg along, still encased in the protective layer of the corona radiata.
At the ovulation
When the follicle bursts, it falls in on itself and gets smaller. The walls of the follicle fold inward, creating a structure called the Corpus hemorrhagicum, which is characterized by blood pooling into the cavity that used to hold the fluid
after the egg is released, the leftover cells undergo a transformation. The granulosa cells (the egg’s support crew) and the theca interna cells (part of the egg’s outer layer) change into two new types of cells: granulosa lutein cells and theca lutein cells. Together, these cells form a new structure called the corpus luteum.
The corpus luteum is a special, temporary gland that’s rich in blood vessels. It has a crucial job: producing progesterone. Progesterone is a key hormone that helps prepare the body for pregnancy and keeps it going in the early stages.
Corpus luteum formation
When an egg gets fertilized, the corpus luteum sticks around to help.
If there’s no fertilization, the corpus luteum fades away and turns into a scar-like tissue called the Corpus Albicans.
the corpus leteum cycle
Atretic Follicles: These are egg “houses” that didn’t make it. They’re winding down and not active.
Forming Corpus Luteum: This is an egg “house” that did its job and is now turning into a temporary hormone factory.
Corpus Albicans: This is what’s left after the temporary hormone factory shuts down. It’s like a little scar inside the ovary.
So basically, you start with lots of potential egg “houses,” one takes the lead, turns into a hormone factory if the egg isn’t fertilized, and then winds down into a tiny scar. Each step is part of the cycle your body goes through every month.
ovaries
oviducts ( Fallopian tubes )
he tubes you’re talking about are the fallopian tubes. They’re like twisty straws attached to the uterus at one end. Their job is to help the egg travel from the ovary, where it’s released, to the uterus. If a sperm is around and fertilization is going to happen, it usually takes place in these tubes.
Infundibulum:
s a wide distal portion of the uterine tube
ampulla
isthmus
Uterine tube
Uterine part: Is the intramural segment of the uterine
tube located within the wall of the uterus
uterine tube
infundibulum
The fallopian tubes hover close but aren’t stuck to the ovaries. During ovulation, the egg pops out and is scooped up by the infundibulum, which is like a funnel-shaped entrance at the end of the tube nearest to the ovary.
Uterine tube
The uterine tube walls lined with smooth
muscle and cilia
Used to guide fertilized oocyte (zygote) to the
uterus
Delicate muscle contractions & gentle
movements of cilia to help the ova to move to
the site of fertilization
Uterine tube
he Ampulla is the upper portion of the
oviduct (uterine tube) closest to the ovary
It is wider than the isthmus and is the site of
fertilization
isthmus
The uterine tube has a section called the isthmus, which is like the last leg of a relay race track that connects directly to the uterus. The utero-tubal junction (UTJ) is like a narrow gate where the uterus and the uterine tube meet. It’s a checkpoint that selects the strongest sperm to continue on to the isthmus and ampulla for potential fertilization.
once sperm make it past the UTJ, they essentially set up a waiting area by sticking to the walls of the isthmus, the uterine tube’s narrow passage. This strategy boosts the chances of fertilization, especially if there’s a timing mismatch between mating and when the egg is released. In animals like pigs and cattle, this sperm hangout can last for 24 to 48 hours, readying them for the moment an egg arrives.
process of the uterine tube
The released egg is ideally snagged by the infundibulum at the end of the uterine tube. There, it meets a sperm, leading to fertilization. The fertilized egg then travels to the uterine horn, where it settles in for further development into an embryo.
uterus
t is formed by:
- A series of tubular structures, the
cervix (it opens caudally to the vagina)
- the uterine body (in the middle part)
- the uterine horns (they communicate
proximally with the oviducts
The uterine body is the site where semen is
deposited during artificial insemination
In the pregnant cow, after fertilization, the
fertilized egg implants in one of the uterine
horns and allows the embryo to grow
the uterus
s the pregnancy progresses, the uterine
body 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
the uterus 3 layers
The uterus is composed of three layers:
- Perimetrium: Outer layer
- Myometrium: a muscular layer
- Endometrium: the innermost layer
after fertilization
After fertilization:
- The zygote starts dividing and
going thru various stages in its
transformation
- At the same time, it is slowly
moving down the oviduct
towards the uterus
- The blastocyst will attach
(implant) to the uterine
endometrium
the placenta
Layers of soft membranes around the
developing fetus
Amnion: layer immediately around the fetus,
forming the amniotic cavity
The amniotic cavity contains the amniotic fluid
which protects the fetus, and allow its movements
Layers of soft membranes around the
developing fetus
Allantois: layer surrounding the amniotic sac,
forming the allantoic cavity
Enables vascular communication between the
developing mamma and its mother
Layers of soft membranes around the
developing fetus
Chorion: 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
Facilitate exchange of nutrients and waste
products
placenta
The connection where the chorion (a fetal membrane) attaches to the uterus is known as the “chorion-endometrial junction.” This is where the baby’s circulation system in the chorion comes very close to the mom’s circulation in the uterus lining, or endometrium. This setup lets oxygen and nutrients flow from the mother to the baby, and waste products from the baby are carried away into the mother’s blood.
in the placenta
The baby’s circulation system is in the chorion, a membrane on the placenta that sticks to the lining of the uterus. The mother’s circulation is in the endometrium, right where the chorion meets the uterine lining, at the chorion-endometrial junction.
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chorine attachment to the tube
it varies between species
There are different types of placenta between
species, varying their shape, and area of contact
between fetal and maternal tissue
n a diffuse attachment, the chorionic villi, which are tiny finger-like projections, are evenly spread out over the surface of the chorion. This uniform coverage makes it easier for the placenta to detach from the uterus after the baby is delivered, allowing it to be expelled smoothly.
This widespread distribution of attachment sites allows the placenta to detach more easily from the uterus after the baby is born, facilitating its expulsion from the mother.
The attachment sites between the chorion and the uterus cover the entire surface of both the placenta and the uterus. This complete coverage makes it easier for the placenta to detach from the uterus after birth, allowing it to be smoothly expelled from the mother.
cranaucles
Caruncles are circular, thickened areas within the lining of the uterus, formed by the growth of connective tissue just below the surface layer. These unique sites are exclusively where connections with the fetal membrane occur in the uterus.
chorion attachment to the uterus
cervix
This description refers to the cervix, a smooth muscle sphincter situated between the uterus and the vagina. Protruding backward into the vagina, the cervix creates a cul-de-sac known as the cervical fornix, which encircles the cervical opening. This structure plays a crucial role in reproductive health, acting as a gateway between the uterus and vagina.
cervix
Typically, the cervix remains closed, opening only during estrus (the heat cycle) and parturition (childbirth). During estrus, the cervix loosens to allow sperm to enter for fertilization, then seals throughout pregnancy. In the initial phase of labor, contractions of the uterus exert pressure on the softened cervix, gradually forcing it to dilate and facilitate the passage of the newborn.
Vagina
Is a muscular tube that receives the penis at breeding
time and acts as the birth canal at parturition
Located between cervix on cranial end and vulva on
caudal end
the testicles
e testicles vary somewhat between
species in shape, size, and location
Pigs: Located caudal to the sigmoid flexure of
the penis, just ventral to the anus, a position
described as perineal
Horses: the long axis of each testis is nearly
horizontal, and the testes are held close to the
abdominal wal
Ruminants: near the sigmoid flexure of the penis; the
long axis of each testis is nearly vertical, so the scrotum
is dorsoventrally elongate and pendulous
male reproductive system testicles
spermatic cord
Despite variations in location across different species, the fundamental anatomy of the testicles remains consistent. The spermatic cord, which includes blood vessels, nerves, lymph vessels, and the ductus deferens, supports each testis inside the scrotum, ensuring its proper positioning and connection to the body’s reproductive system.
Each testis is composed of tightly coiled seminiferous tubules, all encased within a dense fibrous sheath known as the tunica albuginea. This structure plays a crucial role in sperm production and overall testicular health.
septa
The tunica albuginea extends inward to form several fibrous septa, which partition the testis into smaller compartments called lobules. These septa serve as a supportive framework for both the seminiferous tubules and the interstitial tissue within the testis, ensuring their structural integrity and organization.
The seminiferous tubules serve as the primary site for spermatogenesis, the process through which spermatozoa, or sperm cells, are formed.
male reproductive system
Spermatogenesis, the process of spermatozoa formation, occurs within the seminiferous tubules. These tubules then transport sperm into a network known as the rete testis, which subsequently drains into the efferent ductules.
The interstitial tissue surrounding the seminiferous tubules contains specialized cells known as interstitial cells or Leydig cells. These cells are responsible for producing the male hormone testosterone, a process triggered by the hormone luteinizing hormone (LH).
When stimulated by luteinizing hormone (LH), the interstitial cells, also known as Leydig cells, secrete the male hormone testosterone.
ustentacular cells
The sustentacular cells, also known as Sertoli cells, reside within the seminiferous tubules, where they envelop developing spermatozoa and their precursors. These cells play a vital role in nurturing the maturation process of sperm and mediating the effects of hormones on the germ cells. As cells of the seminiferous tubule, Sertoli cells provide essential support and nourishment to developing spermatozoa, ensuring their proper development.
epidemis
The epididymis is arbitrarily divided into:
- Head: into which the efferent ductules empty
- Body lying on the long axis of the testis
- Tail that is attached by ligaments directly to the
testis and to the adjacent tunica albuginea
tunica albuginea
