Week 3 Flashcards
Where is the pelvic cavity found?
Within the bony pelvis between the pelvic inlet and outlet
Describe the peritoneum.
A thin transparent serous membrane that lines the abdominal cavity and drapes over the pelvic viscera.
What are the pouches created by peritoneum in females?
Vesico-uterine
Rectouterine (Pouch of Douglas)
Why is the rectouterine pouch clinically important?
In an upright female this is the lowest point of the abdominal cavity therefore excess fluid can gather here.
What is the pouch created by the peritoneum called in males?
Rectovesical
What are the primary and accessory organs of the female reproductive system?
Primary - Ovaries
Accessory - Uterine tubes, uterus, vagina.
Describe fimbriae.
Finger like projections that gather the egg when it is released into the cavity.
What are the 3 layers of the uterus?
Perimetrium
Myometrium
Endometrium
Where does fertilisation normally occur?
Ampulla
What is the most common position of the uterus?
Anteverted and anteflexed.
Where do ovaries and testes develop?
Posterior abdominal wall.
What arteries supply the female reproductive system?
Ovarian artery
Uterine artery
Internal iliac artery
What is the inguinal canal?
The route which the testes follow from the abdominal wall creating a tunnel.
What does the dartos muscle do?
A smooth muscle that moves the testes further from and closer to the body to control temperature
Describe the pathway of sperm cells.
Produced in the seminiferous tubule.
Pass into the rete testis.
Then into the head of epididymis which becomes the vas deferens
What are the primary and accessory organs of the male reproductive system?
Primary: Testes
Accessory: Vas deferens, seminal glands, prostate gland, penis.
What gland produces seminal fluid?
Seminal gland.
Where do the right and left ejaculatory ducts join?
Prostate gland.
When do the conceptus, embryonic and foetal period occur?
Conceptus - Weeks 0 - 3.
Embryonic - Weeks 3 -8.
Foetal - Weeks 9 - 40.
What are the 6 phases of embryogenesis?
Gametogenesis
Fertilisation
Cleavage
Gastrulation
Formulation of a body plan
Organogenesis
Describe male and female gametogenesis.
Female - Occurs in utero by weeks 28 - 30 when the gametes arrest in prophase. This is completed in puberty.
Male - Occurs at puberty and continues throughout life.
When do the majority of nondisjunction cases occur?
Oocyte formation
What is nondisjunction?
Incorrect separation of chromosomes in formation
Define polyspermy.
More than one sperm fertilise one egg.
Describe some mechanisms to prevent polyspermy.
The zona pellucida causes cortical granules to release their contents on penetration to render it impenetrable to others.
The zona pellucida depolarises.
What occurs during cleavage of the zygote?
Rapid mitotic division where individual cells get smaller and the structure remains the same size.
The morula then the blastocyst are formed.
What occurs during gastrulation?
The germ layers are formed and the body axis is established.
In what week are the germ layers of the embryo formed?
Week 3
What are the 3 germ layers of the embryo?
Ectoderm
Mesoderm
Endoderm
What does the yolk sac of the embryo become?
The gut tube
During what weeks does organogenesis occur?
4 to 8
Which period does most foetal growth occur in?
The foetal period
What is cell induction?
The ability of one cell type to cause another to differentiate either directly or at a distance.
Describe fertilisation.
Sperm binds with zona pellucida glycoprotein ZP3.
Acrosomal enzymes are released from the sperm head allowing it to digest its way into the egg.
Egg and sperm membranes fuse allowing the sperm entry.
Sperm entry triggers release of cortical granules.