Identification of the Organs of Female Genital System under Microscope.
Welcome again. Hope you are fine. Today, I will discuss the identification of the organs of the female genital system under a microscope. We have already discussed the identification of the organs of the male genital system. If you did not get them, go through this link. Okay, before starting, you should have a basic idea about STRUCTURE OF CELL, LINING EPITHELIUM, CONNECTIVE TISSUE, and GENERAL STRUCTURAL PATTERN OF A TUBULAR ORGAN. If you don’t have basic knowledge about those topics, you may also go through those links.
Here we will discuss the important histological features necessary to identify the organ under a microscope. Okay, let’s start –
Organs of the female genital system:
We need to identify the following organs from the female genital system under a microscope –
Ovary and their follicles
Uterine tube or fallopian tube
Uterus
Vagina
Mammary gland
Let’s start to discuss their important histological feature under a microscope.
Ovary and their follicles:
The ovary has both exocrine and endocrine functions. We will identify the following structure of the ovary under the microscope –
Cortex and medulla of the ovary
Development of different stages of follicles (primordial, primary, secondary, and tertiary follicles)
Structure of a mature or Graafian follicle (secondary oocyte, zona pellucida, cumulus oophorus, corona radiate, liquor folliculi, granulosa cell layers, antrum, basement membrane, theca externa, and theca interna)
Atretic follicle
Structure of corpus luteum
Okay, let’s start to know those structures.
The cortex of the ovary: is the peripheral zone of the ovary and is lined by low cuboidal epithelium. Presence of connective tissue layer called tunica albuginea under the lining epithelium. Different types of follicles and corpus lute are mainly present in the cortex.
The medulla of the ovary: It is the inner portion of the ovary and contains mainly blood vessels, nerves, and lymph vessels in loose connective tissue stroma
Follicles of the ovary: There are mainly four types of ovarian follicles. They are – primordial, primary (unilaminar or multilaminar), secondary and tertiary follicles.
The primordial follicle has a primary oocyte surrounded by a single layer of simple squamous epithelium (called follicular cells). They are present in the outer cortex of the ovary.
Primary follicles have a primary oocyte surrounded by a simple cuboidal epithelium (single or multiple layers of simple cuboidal cells).
Secondary follicles have primary oocytes surrounded by stratified or polyhedral epithelium, follicular, or granulosa cells. In secondary follicles, there forms a fluid fill cleft by the granulosa cells called ANTRUM. A multilaminar layer also formed called theca cell layers (theca interna and theca externa).
Tertiary or growing or Graafian follicles:
We should identify the following structure from a griffin follicle –
Oocyte
Zona pellucida
Corona radiate
Cumulus oophorus
Granulosa cell layer
Antrum with liquor folliculi
Theca interna and externa
Tertiary or growing follicles have a primary or secondary oocyte surrounded by stratified granulosa cells layers.
The plasma membrane of the oocyte is called zona pellucida
Granulosa cells surround the oocyte, called cumulus oophorus, and the granulosa layer that immediately surrounds the oocyte is called corona radiate.
A fluid-filled cavity is formed among the granulosa cells called antrum, and the fluid is called liquor folliculi.
Outside of the granulosa cells, there is a specialized stroma cell called theca layer (theca interna and theca externa).
In the case of theca interna, you will find the spindle-shaped cell with delicate reticular fiber, and in theca externa, you will find a thin layer of loose connective tissue with fibrocytes.
Atretic follicles: Follicles that regress at the development time are called atretic follicles. You will find the following characteristics on atretic follicles-
Folding of granulosa layer
Presence of hyalinization (glassy membrane)
Presence of pyknosis nucleus of granulosa cells
Corpus luteum:
They are also called the temporary endocrine gland. After ovulation, follicles rupture, collapse and shrink to form a corpus lutem. We will find the following characteristics on corpus lutem –
Extensive folding of the follicular wall
Presence of pyknosis in granulosa cell layers
Granulosa cells start to become enlarged (Foamy) and form larger luteal cells and produce progesterone
Theca Interna cells contribute to forming small lutein cells and also produce progesterone.
“For more information, you need to follow the class lecture of your teacher or simply you need to go through the book.”
Uterine tube or fallopian tube or oviduct:
Here, we need the basic idea on GENERAL STRUCTURAL PATTERN OF A TUBULAR ORGAN.
It is known to us that the uterine tube has three parts named infundibulum, ampulla, and isthmus. We will identify the following structures –
Lining epithelium
Lamina propria (lamina muscularis is absent)
Tunica muscularis
Tunica serosa
Okay, let’s start –
Under a microscope, you will find the following characteristics of a uterine tube –
The mucosa of the uterine tube is highly folded (fold are more in ampulla region then gradually decreases) and lined by simple columnar or pseudostratified columnar with cilia.
Presence of thick inner circular muscle and isolated longitudinal muscles layer (in the isthmus, muscle layer are prominent).
Presence of thin layer of loose connective tissue with simple squamous lining
Uterus:
We need to find out the following structure of the uterus –
Endometrium part (Simple columnar lining epithelium, uterine gland)
Myometrium
Perimetrium
Okay, let’s start to identify –
In the case of secretory phages of the uterus
The endometrium has a superficial (functional zone) and deep layer. The superficial layer is lined by simple columnar epithelium (hypertrophied) with loose connective tissue in the case of ruminant. The deep layer consists of loose connective tissue with few connective tissue cells.
Presence of highly coiled, branched, dilated uterine gland
There is a thick inner circular and the outer longitudinal layer of smooth muscles
Presence of loose connective tissue with mesothelium lining
In case of proliferative phage of the uterus
The superficial layer of the endometrium is lined by simple columnar epithelium
Presence of simple straight tubular gland with narrow lumen
Presence of thin layer of inner circular and an outer longitudinal layer of smooth muscles
Vagina:
We need to identify the following structure of the vagina –
Stratified lining epithelium
Propria submucosa
Tunica muscular (two or three layers)
Tunica adventitia
Okay, let’s start to identify –
Presence of stratified squamous epithelium (increases its thickness during proestrus and estrus)
Again, presence of dense irregular connective tissue in propria submucosa
Presence of two or three layers of smooth muscles layers (inner longitudinal, middle circular, and outer longitudinal layer)
Presence of loose connective tissue with blood vessels, the nerve in the tunica adventitia
“Here I am trying to provide important features that are necessary to identify the organs under microscope, if you want to know more, please, follow your class lecture or books.”
Mammary gland:
You need to identify the lactating and non-lactating mammary glands under a microscope. we will identify the following structures of the mammary gland under the microscope –
Glandular lobule
Alveoli
Interlobular connective tissue
Secretory alveoli with milk
Okay, let’s start –
In the case of the non-lactating mammary gland, you will find the following characteristics –
Presence of more connective tissue and less glandular tissue
A gland is lined by simple cuboidal epithelium
Presence of underdeveloped milk alveoli system
Presence of more duct system
The lumen of the duct is not visible
The interlobular connective tissue septum is thicker
In the case of the lactating mammary gland, you will find the following characteristics –
Presence of more glandular tissue and less connective tissue
The gland is lined by simple cuboidal epithelium
Presence of branched, well-developed milk alveoli with a dilated lumen
The interlobular connective tissue septum is thinner compared to the non-lactating mammary gland
Conclusion
I hope you have got an idea of identifying organs of the female genital system under a microscope. You may also learn the basic histology of the organs from DIGESTIVE SYSTEM, RESPIRATORY SYSTEM, URINARY SYSTEM, and MALE GENITAL SYSTEM. If you want to get more information on those topics, you should follow the class lecture or go through the BOOK for more.
Again, If possible, I will update or enrich the information on this topic in the future.
If there is any mistake in the above information or if you have any suggestions for me, please, let me know in the comment box. Thank you so much.