10. Female Histology Flashcards
What are the functions of ovary
- Produces gametes - Produces hormones - Responsive to circulating hormone - Functioning reduced at menopause
How are the ovaries attached to the posterior face?
Broad ligament
What ligament anchors the ovary to the uterus?
Ovarian ligament
What structure anchor the ovary to the pelvic wall
Suspensory ligament
Diagram of Uterus and ovary
What are the structural divisons of the ovary?
- Inner medulla
- Loose connective tissue and blood vessels
- Outer cortex
- Location of ovarian follicles - oocyles
- cortical stroma is highly cellular connective tissue with scattered smooth muscle walls
- Contains many primordial oocytes and multiple maturing oocytes
What causes the irregularity of on the ovary structure?
Scarring from the release of oocytes
Ovarian structure under low power
Describe the structural layes of the Ovary
Starting form the outside in, there is mesothelum running across the surface of the ovary.
On the ovary its often squamous but sometimes cuboidal.
Mesothelium is continuous with the same one that run on the broad ligament and uterus.
Underneath the epithelium is a layer of connective tissue called the Tunica Albugenia (dense connective tissue). Once you enter the Tunica Albugenia you start to see oocytes.
The smooth muscles give the red tinge which penetrate the deep connective thssie (this is the area which produce force)
Where do most ovarian tumours arise from?
70% of ovarian tumours arise from the surface simple epithelium (squamous or cuboidal) continuous with mesothelium
Oocyte numbers
- 5 million per ovary in embryo
- 0.5 million by birth
- Most degenerate over time
- a few thousand go through most of a maturation cycle and around 500 are released into the fallopian tube
What are primordial oocytes?
- Smallest oocytes
- on outside are squaous follicle cells surrounded by common basal lamina
- Oocyte is arrested in prophase of meiosis 1 (incomplete meiotic divisio)
What are primary oocytes
- Oocyte now surrounded by zona pellucida (within follicle cell layer)
- Oocyte enlarges, follicular cells become cuboidal and multilayered granulosa cells (form stratum granulosum)
- Surrounding stromal cells stat to form theca interna and externa (surround stratum granulosum)
What are secondary follicle?
Primary oocyte becomes a secondary follicle.
Called follicle because it involves many cells.
- As stratum granulosum thickens, a fluid filled cavity (antrum) appears
- Oocyte suspended on stalk of granulosa cells (cumulus oophorus)
- Granulosa cells around oocyte form corona radiata after release
What happens during ovulation?
- Matrua follicle is called Graafian follicle
- Under LH, oocyte completes first meiotic division (started years ago)
- Now secondary oocyte
- Follicle ruptures
- Oocyte released into body cavity and can enter fallopian tube - lasts 24 hours
Describe the structure of Fallopian tubes
- Where sperm and egg unite
- Provide environment for fertilisation and initial development
- Expanded opening (infundibulum) apposes ovary and has fimbriae collects released ooctyes
Widest at the infundibulum and narrow down into the isthmus.
Ampulla
- Thin smooth muscle wall
- Extensive excretory mucosa
- Epithelium that lines it is cilia to provide a current of fluid
Isthmus
- Smaller hole
- Less extensive mucosa
Muscular wall to guide movement of cilia + compressing the wall (like peristalsis)
Fluid secreted by epithelium provides nutrients for oocyte
Fertilisation usually occurs in ampulla, zygote remains for three days in isthmus
What is the structure of the uterine wall?
- Divided into a mucosa (endometrium), muscularis (myometrium)
- An outer perimetrium covers most of the external surface and consists of mesothelium and underlying elastic connective tissue
- Myometrium and endometrium respond to cylic hormonal changes that drive menstrual cycle
What is the structure of the endometrium?
- Epithelium is ciliated and secretory columnar cells in simple epithelium
- Secretory glands (no ciliated cells) penetrate into lamina propria (endometrial stroma - highly cellular, rich in ground substance and reticular fibres not fibrous - like mesenchyme - embryonic connective tissue)
- Mucosa supplied by helical cells
- Functional layer sloughed off each menstrual cycle
- Basal layer regenerates functional layer
How does the endometrium change during menstrual cycle
- Endometrium changes thickness during cycle
- Groth is driven by estrogen intially and breakdown by later decrease of estrogen and progesterone
- Fertilisation maintains corpus luteum and progesterone and estrogen levels
Describe the structure of the cervix
- Endocervix (Uterine cervix)
○ Same epithelium as cervix
○ Heavily secretory/Glandular
○ Secretions are modified according to the stage of ovulatory cycle
○ Can provide mucus that block the cervix (block infection) but to allow fertilization it provides environment for sperm - Ectocervicx (Vaginal Cervix)
○ Facing the outside wall
○ Major issue is pathogen coming from outside
○ Epithelium is stratified squamous
○ Kept dry
○ Non glandular
Has to be defended strongly
J = boundary between ectocervix and endocervix.
Boundary changes depending on the ovarian cycle. This region is prone to cancerous change, can be monitored because ectocervis are constantly shedding.
This is the basis of Pap Smear.
Vagina microscope
- Stratified squamous epithelium is non-keratinised
- Most superficial cells retain nuclei
What is the structure of breast?
Multiple opening around the nipple.
Mammary gland is embedded around connective tissue.
But most of breast is adipose tissue.
What is the histology of inactive mammary glands like?
What happens to the mammary glands during pregnancy?
- Dramatic response to new hormone levels
- Terminal ductules elongate and branch
- Epithelial and myoepithelial cells proliferate from progenitor cells
- By term, have large cuboidal epithelial cells containing lipid and secretory product in lumen
- Breast is enlarged as a result of growth
