Histology of the Male Histology of the Male

Genital System (2)Genital System (2)

Histology of the Male Histology of the Male

Genital System (2)Genital System (2)

The Male Genital SystemThe Male Genital SystemThe Male Genital SystemThe Male Genital SystemThe male genital system consists of:The male genital system consists of:

1.1. Primary sex organPrimary sex organ: two testes.: two testes.2.2. Accessory sex organsAccessory sex organs: accessory glands : accessory glands

and excretory ducts.and excretory ducts.Accessory glands: seminal vesicle, Accessory glands: seminal vesicle, prostate, bulbo-urethral galnds.prostate, bulbo-urethral galnds.Excretory ducts: tubuli recti, rete testis, Excretory ducts: tubuli recti, rete testis, ductuli efferentes, epididymis, vas ductuli efferentes, epididymis, vas deferens, ampulla of vas deferens, deferens, ampulla of vas deferens, ejaculatory duct and urethra.ejaculatory duct and urethra.

The male genital system consists of:The male genital system consists of:1.1. Primary sex organPrimary sex organ: two testes.: two testes.2.2. Accessory sex organsAccessory sex organs: accessory glands : accessory glands

and excretory ducts.and excretory ducts.Accessory glands: seminal vesicle, Accessory glands: seminal vesicle, prostate, bulbo-urethral galnds.prostate, bulbo-urethral galnds.Excretory ducts: tubuli recti, rete testis, Excretory ducts: tubuli recti, rete testis, ductuli efferentes, epididymis, vas ductuli efferentes, epididymis, vas deferens, ampulla of vas deferens, deferens, ampulla of vas deferens, ejaculatory duct and urethra.ejaculatory duct and urethra.

The TestisThe TestisThe TestisThe Testis

The TestisThe TestisThe TestisThe TestisThe test is a The test is a compound tubularcompound tubular mixed mixed gland formed of gland formed of stroma and parenchymastroma and parenchymaThe The stromastroma (capsule, septa and reticular (capsule, septa and reticular connective tissue).connective tissue).The capsule has 3 coatsThe capsule has 3 coats::

1.1. Tunica vaginalisTunica vaginalis (parietal and visceral (parietal and visceral layers) lined with simple squamous epith.layers) lined with simple squamous epith.

2.2. Tunica albugeniaTunica albugenia: condensed collagenous : condensed collagenous fibers, thickened posteriorly to form the fibers, thickened posteriorly to form the mediastinum testis.mediastinum testis.

3.3. Tunica vasculosaTunica vasculosa: areolar connective : areolar connective Tissue rich in blood capillaries.Tissue rich in blood capillaries.

The test is a The test is a compound tubularcompound tubular mixed mixed gland formed of gland formed of stroma and parenchymastroma and parenchymaThe The stromastroma (capsule, septa and reticular (capsule, septa and reticular connective tissue).connective tissue).The capsule has 3 coatsThe capsule has 3 coats::

1.1. Tunica vaginalisTunica vaginalis (parietal and visceral (parietal and visceral layers) lined with simple squamous epith.layers) lined with simple squamous epith.

2.2. Tunica albugeniaTunica albugenia: condensed collagenous : condensed collagenous fibers, thickened posteriorly to form the fibers, thickened posteriorly to form the mediastinum testis.mediastinum testis.

3.3. Tunica vasculosaTunica vasculosa: areolar connective : areolar connective Tissue rich in blood capillaries.Tissue rich in blood capillaries.

The TestisThe TestisThe TestisThe TestisFrom the mediastinum testis, From the mediastinum testis, incomplete septa arise and extends to incomplete septa arise and extends to the deep surface of the tunica the deep surface of the tunica albuginea and divide the testis into 250 albuginea and divide the testis into 250 compartments or lobules.compartments or lobules.

Each testicular lobule contains 1-4 Each testicular lobule contains 1-4 highly convoluted seminiferous highly convoluted seminiferous tubules.tubules.

From the mediastinum testis, From the mediastinum testis, incomplete septa arise and extends to incomplete septa arise and extends to the deep surface of the tunica the deep surface of the tunica albuginea and divide the testis into 250 albuginea and divide the testis into 250 compartments or lobules.compartments or lobules.

Each testicular lobule contains 1-4 Each testicular lobule contains 1-4 highly convoluted seminiferous highly convoluted seminiferous tubules.tubules.

Parenchyma of The TestisParenchyma of The TestisParenchyma of The TestisParenchyma of The TestisIt divides into It divides into exocrine partexocrine part which produces which produces sperms (seminiferous tubules) and sperms (seminiferous tubules) and endocrine endocrine partpart which secretes testosterone (interstitial cells which secretes testosterone (interstitial cells of Leydig).of Leydig).Seminiferous tubule is 50 cm in length, 200 Seminiferous tubule is 50 cm in length, 200 micron in diameter, having clear basement micron in diameter, having clear basement membrane surounded by reticular connective membrane surounded by reticular connective tissue and smooth muscle fibers.tissue and smooth muscle fibers.The seminiferous tubule is lined with two types of The seminiferous tubule is lined with two types of cells:cells:

1.1. Spermatogenic cellsSpermatogenic cells: stratified and produce : stratified and produce sperms.sperms.

2.2. Sertoli cellsSertoli cells: Unilaminar supporting, protective : Unilaminar supporting, protective and nutritive cells.and nutritive cells.

It divides into It divides into exocrine partexocrine part which produces which produces sperms (seminiferous tubules) and sperms (seminiferous tubules) and endocrine endocrine partpart which secretes testosterone (interstitial cells which secretes testosterone (interstitial cells of Leydig).of Leydig).Seminiferous tubule is 50 cm in length, 200 Seminiferous tubule is 50 cm in length, 200 micron in diameter, having clear basement micron in diameter, having clear basement membrane surounded by reticular connective membrane surounded by reticular connective tissue and smooth muscle fibers.tissue and smooth muscle fibers.The seminiferous tubule is lined with two types of The seminiferous tubule is lined with two types of cells:cells:

1.1. Spermatogenic cellsSpermatogenic cells: stratified and produce : stratified and produce sperms.sperms.

2.2. Sertoli cellsSertoli cells: Unilaminar supporting, protective : Unilaminar supporting, protective and nutritive cells.and nutritive cells.

(1) Spermatogia(1) Spermatogia(1) Spermatogia(1) SpermatogiaSpermatogoniaSpermatogonia: rest on the basement : rest on the basement membrane, small cells with small nuclei.membrane, small cells with small nuclei.At puberty, they divide to give two subtypes At puberty, they divide to give two subtypes of spermatogonia:of spermatogonia:

A.A. Type A spermatogoniaType A spermatogonia: with fine chromatin : with fine chromatin granules that stain lightly, some of them granules that stain lightly, some of them remains as stem cells and other redivide to remains as stem cells and other redivide to give Type B spermatogonia.give Type B spermatogonia.

B.B. Type B spermatogoniaType B spermatogonia: larger cells with : larger cells with coarse chromatin granules which stain coarse chromatin granules which stain darkly. They divide to give the primary darkly. They divide to give the primary spermatocytes.spermatocytes.

SpermatogoniaSpermatogonia: rest on the basement : rest on the basement membrane, small cells with small nuclei.membrane, small cells with small nuclei.At puberty, they divide to give two subtypes At puberty, they divide to give two subtypes of spermatogonia:of spermatogonia:

A.A. Type A spermatogoniaType A spermatogonia: with fine chromatin : with fine chromatin granules that stain lightly, some of them granules that stain lightly, some of them remains as stem cells and other redivide to remains as stem cells and other redivide to give Type B spermatogonia.give Type B spermatogonia.

B.B. Type B spermatogoniaType B spermatogonia: larger cells with : larger cells with coarse chromatin granules which stain coarse chromatin granules which stain darkly. They divide to give the primary darkly. They divide to give the primary spermatocytes.spermatocytes.

(2) Primary Spermatocytes(2) Primary Spermatocytes(2) Primary Spermatocytes(2) Primary SpermatocytesPrimary spermatocytesPrimary spermatocytes are the largest are the largest of all spermatogenic cells.of all spermatogenic cells.

Each cell has Each cell has 23 pairs23 pairs of chromosomes. of chromosomes.

Each cell contains coiled chromosomes Each cell contains coiled chromosomes in their its large nucleus.in their its large nucleus.

Each cell undergoes its first meiotic Each cell undergoes its first meiotic division giving rise to smaller cells division giving rise to smaller cells called called secondary spermatocytessecondary spermatocytes..

Primary spermatocytesPrimary spermatocytes are the largest are the largest of all spermatogenic cells.of all spermatogenic cells.

Each cell has Each cell has 23 pairs23 pairs of chromosomes. of chromosomes.

Each cell contains coiled chromosomes Each cell contains coiled chromosomes in their its large nucleus.in their its large nucleus.

Each cell undergoes its first meiotic Each cell undergoes its first meiotic division giving rise to smaller cells division giving rise to smaller cells called called secondary spermatocytessecondary spermatocytes..

(3) Secondary Spermatocytes(3) Secondary Spermatocytes(3) Secondary Spermatocytes(3) Secondary SpermatocytesSecondary spermatocytesSecondary spermatocytes are the are the daughter cells of primary daughter cells of primary spermatocytes.spermatocytes.They are small cells with small nuclei They are small cells with small nuclei having granular chromatin, and live for having granular chromatin, and live for a short time.a short time.Each cell has Each cell has haploid numberhaploid number of of chromosomes (23 only).chromosomes (23 only).They enter quickly to the second They enter quickly to the second meiotic division to form meiotic division to form spermatidsspermatids..

Secondary spermatocytesSecondary spermatocytes are the are the daughter cells of primary daughter cells of primary spermatocytes.spermatocytes.They are small cells with small nuclei They are small cells with small nuclei having granular chromatin, and live for having granular chromatin, and live for a short time.a short time.Each cell has Each cell has haploid numberhaploid number of of chromosomes (23 only).chromosomes (23 only).They enter quickly to the second They enter quickly to the second meiotic division to form meiotic division to form spermatidsspermatids..

(4) Spermatids(4) Spermatids(4) Spermatids(4) SpermatidsSpermatidsSpermatids are very small cells with are very small cells with deeply stained elongated nuclei.deeply stained elongated nuclei.They are present in the center of the They are present in the center of the seminiferous tubule near Sertoli cells.seminiferous tubule near Sertoli cells.They have They have haploidhaploid number of number of chromosomes (23) and chromosomes (23) and haploidhaploid DNA DNA contents.contents.Each spermatid undergoes a process of Each spermatid undergoes a process of spermiogenesisspermiogenesis to be transformed into to be transformed into spermatozoonspermatozoon..

SpermatidsSpermatids are very small cells with are very small cells with deeply stained elongated nuclei.deeply stained elongated nuclei.They are present in the center of the They are present in the center of the seminiferous tubule near Sertoli cells.seminiferous tubule near Sertoli cells.They have They have haploidhaploid number of number of chromosomes (23) and chromosomes (23) and haploidhaploid DNA DNA contents.contents.Each spermatid undergoes a process of Each spermatid undergoes a process of spermiogenesisspermiogenesis to be transformed into to be transformed into spermatozoonspermatozoon..

(5) Mature sperm(5) Mature sperm(5) Mature sperm(5) Mature spermA SpermA Sperm is a highly motile body that consists of:is a highly motile body that consists of:

1)1) The head:The head: pyriform in shape, formed mainly of pyriform in shape, formed mainly of the nucleus. Its anterior 2/3 is covered by the nucleus. Its anterior 2/3 is covered by acrosomal cap which is rich in hydrolytic acrosomal cap which is rich in hydrolytic enzymes that dissolve the zona pellucida of the enzymes that dissolve the zona pellucida of the ovum to facilitaate fertilization.ovum to facilitaate fertilization.

2)2) The tail:The tail: which is subdivided into four parts: which is subdivided into four parts:1.1. The neckThe neck: containing the centrioles.: containing the centrioles.2.2. The middle pieceThe middle piece: containing the mitochondria.: containing the mitochondria.3.3. The principal pieceThe principal piece: containing outer fibrous : containing outer fibrous

sheath.sheath.4.4. The end pieceThe end piece: central axoneme surounded by : central axoneme surounded by

plasmalemma.plasmalemma.

A SpermA Sperm is a highly motile body that consists of:is a highly motile body that consists of:1)1) The head:The head: pyriform in shape, formed mainly of pyriform in shape, formed mainly of

the nucleus. Its anterior 2/3 is covered by the nucleus. Its anterior 2/3 is covered by acrosomal cap which is rich in hydrolytic acrosomal cap which is rich in hydrolytic enzymes that dissolve the zona pellucida of the enzymes that dissolve the zona pellucida of the ovum to facilitaate fertilization.ovum to facilitaate fertilization.

2)2) The tail:The tail: which is subdivided into four parts: which is subdivided into four parts:1.1. The neckThe neck: containing the centrioles.: containing the centrioles.2.2. The middle pieceThe middle piece: containing the mitochondria.: containing the mitochondria.3.3. The principal pieceThe principal piece: containing outer fibrous : containing outer fibrous

sheath.sheath.4.4. The end pieceThe end piece: central axoneme surounded by : central axoneme surounded by

plasmalemma.plasmalemma.

DefinitionsDefinitionsDefinitionsDefinitionsSpermatogenesisSpermatogenesis: : formation of sperms from formation of sperms from spermatogonic cells. It divides into 3 phases:spermatogonic cells. It divides into 3 phases:

1.1. SpermatocytogenesisSpermatocytogenesis: spermatogonia (2n : spermatogonia (2n chromosomes and 2n DNA) give primary chromosomes and 2n DNA) give primary spermatocytes (2n chromosomes and 2n DNA).spermatocytes (2n chromosomes and 2n DNA).

2.2. MeiosisMeiosis: which subdivides into:: which subdivides into:1.1. First meiotic divisionFirst meiotic division: primary spermatocytes (2n : primary spermatocytes (2n

chromosomes and 4n DNA) give secondary chromosomes and 4n DNA) give secondary spermatocytes (n chromosomes and 2n DNA).spermatocytes (n chromosomes and 2n DNA).

2.2. Second meiotic divisionSecond meiotic division: secondary spermatocytes : secondary spermatocytes give spermatids (n chromosomes and n DNA).give spermatids (n chromosomes and n DNA).

3.3. SpermiogenesisSpermiogenesis: differentiation of spermatids into : differentiation of spermatids into mature spermsmature sperms

SpermatogenesisSpermatogenesis: : formation of sperms from formation of sperms from spermatogonic cells. It divides into 3 phases:spermatogonic cells. It divides into 3 phases:

1.1. SpermatocytogenesisSpermatocytogenesis: spermatogonia (2n : spermatogonia (2n chromosomes and 2n DNA) give primary chromosomes and 2n DNA) give primary spermatocytes (2n chromosomes and 2n DNA).spermatocytes (2n chromosomes and 2n DNA).

2.2. MeiosisMeiosis: which subdivides into:: which subdivides into:1.1. First meiotic divisionFirst meiotic division: primary spermatocytes (2n : primary spermatocytes (2n

chromosomes and 4n DNA) give secondary chromosomes and 4n DNA) give secondary spermatocytes (n chromosomes and 2n DNA).spermatocytes (n chromosomes and 2n DNA).

2.2. Second meiotic divisionSecond meiotic division: secondary spermatocytes : secondary spermatocytes give spermatids (n chromosomes and n DNA).give spermatids (n chromosomes and n DNA).

3.3. SpermiogenesisSpermiogenesis: differentiation of spermatids into : differentiation of spermatids into mature spermsmature sperms

SpermiogenesisSpermiogenesisSpermiogenesisSpermiogenesisSpermiogenesisSpermiogenesis: differentiation of : differentiation of spermatids into mature sperms:spermatids into mature sperms:

1.1. Formation of the acrosomal cap.Formation of the acrosomal cap.2.2. Elongation, condensation and flattening of Elongation, condensation and flattening of

the nucleus.the nucleus.3.3. Changes in the centrioles and fomation of Changes in the centrioles and fomation of

the flagellum.the flagellum.4.4. Arrangement of the mitochondria as a Arrangement of the mitochondria as a

spiral structure around the first part of the spiral structure around the first part of the tail.tail.

5.5. Discharge of the cytoplasm and other Discharge of the cytoplasm and other organelles of no use by the sperm.organelles of no use by the sperm.

SpermiogenesisSpermiogenesis: differentiation of : differentiation of spermatids into mature sperms:spermatids into mature sperms:

1.1. Formation of the acrosomal cap.Formation of the acrosomal cap.2.2. Elongation, condensation and flattening of Elongation, condensation and flattening of

the nucleus.the nucleus.3.3. Changes in the centrioles and fomation of Changes in the centrioles and fomation of

the flagellum.the flagellum.4.4. Arrangement of the mitochondria as a Arrangement of the mitochondria as a

spiral structure around the first part of the spiral structure around the first part of the tail.tail.

5.5. Discharge of the cytoplasm and other Discharge of the cytoplasm and other organelles of no use by the sperm.organelles of no use by the sperm.

Sertoli CellsSertoli CellsSertoli CellsSertoli CellsThey are pyramidal-shaped cells resting on the They are pyramidal-shaped cells resting on the basement membrane of the seminiferous tubule basement membrane of the seminiferous tubule and extend till its lumen.and extend till its lumen.They are interposed between the spermatogenic They are interposed between the spermatogenic cells.cells.They have pale cytoplasm containing RER, SER, They have pale cytoplasm containing RER, SER, Golgi apparatus, lysosomes, lipid droplets, Golgi apparatus, lysosomes, lipid droplets, glycogen granules, microtubules, filaments and glycogen granules, microtubules, filaments and mitochondria.mitochondria.They have large, basal, elongated euchromatic They have large, basal, elongated euchromatic nuclei.nuclei.The basal part of the lateral walls are united by The basal part of the lateral walls are united by tight junctions which constitute blood-testis tight junctions which constitute blood-testis barrier.barrier.

They are pyramidal-shaped cells resting on the They are pyramidal-shaped cells resting on the basement membrane of the seminiferous tubule basement membrane of the seminiferous tubule and extend till its lumen.and extend till its lumen.They are interposed between the spermatogenic They are interposed between the spermatogenic cells.cells.They have pale cytoplasm containing RER, SER, They have pale cytoplasm containing RER, SER, Golgi apparatus, lysosomes, lipid droplets, Golgi apparatus, lysosomes, lipid droplets, glycogen granules, microtubules, filaments and glycogen granules, microtubules, filaments and mitochondria.mitochondria.They have large, basal, elongated euchromatic They have large, basal, elongated euchromatic nuclei.nuclei.The basal part of the lateral walls are united by The basal part of the lateral walls are united by tight junctions which constitute blood-testis tight junctions which constitute blood-testis barrier.barrier.

Blood-testis barrierBlood-testis barrierBlood-testis barrierBlood-testis barrierIt is the It is the tight junctionstight junctions between the basal parts of the between the basal parts of the Sertoli cells which isolate the spermatogonia from Sertoli cells which isolate the spermatogonia from the other spermatogenic cells.the other spermatogenic cells.This barrier divides the seminiferous tubules into This barrier divides the seminiferous tubules into basal compartmentbasal compartment (containing spermatogonia) and (containing spermatogonia) and adluminal compartmentadluminal compartment (containing spermatocytes, (containing spermatocytes, spermatids and sperms).spermatids and sperms).Functions of blood-testis barrierFunctions of blood-testis barrier::

1.1. Selects the nutrients, hormones and other Selects the nutrients, hormones and other structures needed for the spermatogenic cells.structures needed for the spermatogenic cells.

2.2. Isolates and protects the spematogenic cells from Isolates and protects the spematogenic cells from any damaging materials, antigen or antibodies in any damaging materials, antigen or antibodies in the circulating blood.the circulating blood.

3.3. Prevents leakage of testicular fluid and androgen-Prevents leakage of testicular fluid and androgen-binding protein secreted by Sertoli cells to the binding protein secreted by Sertoli cells to the interstitial tissues.interstitial tissues.

It is the It is the tight junctionstight junctions between the basal parts of the between the basal parts of the Sertoli cells which isolate the spermatogonia from Sertoli cells which isolate the spermatogonia from the other spermatogenic cells.the other spermatogenic cells.This barrier divides the seminiferous tubules into This barrier divides the seminiferous tubules into basal compartmentbasal compartment (containing spermatogonia) and (containing spermatogonia) and adluminal compartmentadluminal compartment (containing spermatocytes, (containing spermatocytes, spermatids and sperms).spermatids and sperms).Functions of blood-testis barrierFunctions of blood-testis barrier::

1.1. Selects the nutrients, hormones and other Selects the nutrients, hormones and other structures needed for the spermatogenic cells.structures needed for the spermatogenic cells.

2.2. Isolates and protects the spematogenic cells from Isolates and protects the spematogenic cells from any damaging materials, antigen or antibodies in any damaging materials, antigen or antibodies in the circulating blood.the circulating blood.

3.3. Prevents leakage of testicular fluid and androgen-Prevents leakage of testicular fluid and androgen-binding protein secreted by Sertoli cells to the binding protein secreted by Sertoli cells to the interstitial tissues.interstitial tissues.

Functions of Sertoli CellsFunctions of Sertoli CellsFunctions of Sertoli CellsFunctions of Sertoli Cells1.1. Support, protection, nutrition, Support, protection, nutrition,

regulation and release of sperms.regulation and release of sperms.2.2. Phagocytosis of degenerative Phagocytosis of degenerative

cells and debris.cells and debris.3.3. Secretion of testicular fluid and Secretion of testicular fluid and

androgen-binding proteins.androgen-binding proteins.4.4. Formation of blood-testis barrier.Formation of blood-testis barrier.5.5. Secretion of small amounts of Secretion of small amounts of

testosterone.testosterone.

1.1. Support, protection, nutrition, Support, protection, nutrition, regulation and release of sperms.regulation and release of sperms.

2.2. Phagocytosis of degenerative Phagocytosis of degenerative cells and debris.cells and debris.

3.3. Secretion of testicular fluid and Secretion of testicular fluid and androgen-binding proteins.androgen-binding proteins.

4.4. Formation of blood-testis barrier.Formation of blood-testis barrier.5.5. Secretion of small amounts of Secretion of small amounts of

testosterone.testosterone.

Interstitial cells of LeydigInterstitial cells of LeydigInterstitial cells of LeydigInterstitial cells of LeydigThey are mesenchymal cells, rounded or They are mesenchymal cells, rounded or polygonal in shape.polygonal in shape.They have euchromatic central nuclei and They have euchromatic central nuclei and acidophilic cytoplasm.acidophilic cytoplasm.The cytoplasm is rich in SER and lipid The cytoplasm is rich in SER and lipid droplets. It also contains RER, Golgi droplets. It also contains RER, Golgi apparatus, lysosomes and lipofuscin apparatus, lysosomes and lipofuscin pigments.pigments.They form the endocrine part of the testis They form the endocrine part of the testis because they produce and secrete the because they produce and secrete the testosterone under the control of ICSH (LH) testosterone under the control of ICSH (LH) of the anterior lobe of the pituitary gland.of the anterior lobe of the pituitary gland.

They are mesenchymal cells, rounded or They are mesenchymal cells, rounded or polygonal in shape.polygonal in shape.They have euchromatic central nuclei and They have euchromatic central nuclei and acidophilic cytoplasm.acidophilic cytoplasm.The cytoplasm is rich in SER and lipid The cytoplasm is rich in SER and lipid droplets. It also contains RER, Golgi droplets. It also contains RER, Golgi apparatus, lysosomes and lipofuscin apparatus, lysosomes and lipofuscin pigments.pigments.They form the endocrine part of the testis They form the endocrine part of the testis because they produce and secrete the because they produce and secrete the testosterone under the control of ICSH (LH) testosterone under the control of ICSH (LH) of the anterior lobe of the pituitary gland.of the anterior lobe of the pituitary gland.

Male Genital Ducts.Male Genital Ducts.Male Genital Ducts.Male Genital Ducts.

1.1. Tubuli recti.Tubuli recti.2.2. Rete testis.Rete testis.3.3. Efferent ductules.Efferent ductules.4.4. Epididymis.Epididymis.5.5. Vas deferens.Vas deferens.6.6. Ejaculatory duct.Ejaculatory duct.7.7. Male urethra.Male urethra.

1.1. Tubuli recti.Tubuli recti.2.2. Rete testis.Rete testis.3.3. Efferent ductules.Efferent ductules.4.4. Epididymis.Epididymis.5.5. Vas deferens.Vas deferens.6.6. Ejaculatory duct.Ejaculatory duct.7.7. Male urethra.Male urethra.

The Tubuli RectiThe Tubuli RectiThe Tubuli RectiThe Tubuli RectiThey have narrow diameter and are lined They have narrow diameter and are lined by simple columnar epithelium.by simple columnar epithelium.They connect the sminiferous tubules with They connect the sminiferous tubules with the rete testis.the rete testis.

They have narrow diameter and are lined They have narrow diameter and are lined by simple columnar epithelium.by simple columnar epithelium.They connect the sminiferous tubules with They connect the sminiferous tubules with the rete testis.the rete testis.

The Rete TestisThe Rete TestisThe Rete TestisThe Rete TestisThey are located in the mediastinum testis They are located in the mediastinum testis and forms a network of anastomosing and forms a network of anastomosing channels surrounded by vascular bed.channels surrounded by vascular bed.They are lined by cuboidal epithelium.They are lined by cuboidal epithelium.

They are located in the mediastinum testis They are located in the mediastinum testis and forms a network of anastomosing and forms a network of anastomosing channels surrounded by vascular bed.channels surrounded by vascular bed.They are lined by cuboidal epithelium.They are lined by cuboidal epithelium.

Efferent DuctulesEfferent DuctulesEfferent DuctulesEfferent DuctulesThey connect the rete testis to the head of the They connect the rete testis to the head of the epididymis.epididymis.They are lined by two types of cells:They are lined by two types of cells:

1.1. Low columnar non-ciliated cells (for absorption Low columnar non-ciliated cells (for absorption of testicular fluid).of testicular fluid).

2.2. High columnar ciliated cells (for moving the High columnar ciliated cells (for moving the non-motile sperms toward the epididymis).non-motile sperms toward the epididymis).The cells rest on basement membrane which is The cells rest on basement membrane which is surrounded by connective tissue containing surrounded by connective tissue containing elastic fibers and smooth muscle fibers.elastic fibers and smooth muscle fibers.The lumen of the efferent ductules appears as The lumen of the efferent ductules appears as festooned because of the alternating tall and festooned because of the alternating tall and short columnar epithelial cells.short columnar epithelial cells.

They connect the rete testis to the head of the They connect the rete testis to the head of the epididymis.epididymis.They are lined by two types of cells:They are lined by two types of cells:

1.1. Low columnar non-ciliated cells (for absorption Low columnar non-ciliated cells (for absorption of testicular fluid).of testicular fluid).

2.2. High columnar ciliated cells (for moving the High columnar ciliated cells (for moving the non-motile sperms toward the epididymis).non-motile sperms toward the epididymis).The cells rest on basement membrane which is The cells rest on basement membrane which is surrounded by connective tissue containing surrounded by connective tissue containing elastic fibers and smooth muscle fibers.elastic fibers and smooth muscle fibers.The lumen of the efferent ductules appears as The lumen of the efferent ductules appears as festooned because of the alternating tall and festooned because of the alternating tall and short columnar epithelial cells.short columnar epithelial cells.

EpididymisEpididymisEpididymisEpididymisIt is a highly coiled 6 m. tube lined with It is a highly coiled 6 m. tube lined with pseudostratified ciliated columnar pseudostratified ciliated columnar epithelium.epithelium.The cilia are non-motile (stereocilia).The cilia are non-motile (stereocilia).The epithelium rests on basement The epithelium rests on basement membrane surrounded by vascular membrane surrounded by vascular connective tissue containing smooth connective tissue containing smooth muscle fibers and elastic fibers.muscle fibers and elastic fibers.Its functins are absorption of the testicular Its functins are absorption of the testicular fluid, storage and maturation of the fluid, storage and maturation of the sperms and propulsion of the sperms sperms and propulsion of the sperms during ejaculation.during ejaculation.

It is a highly coiled 6 m. tube lined with It is a highly coiled 6 m. tube lined with pseudostratified ciliated columnar pseudostratified ciliated columnar epithelium.epithelium.The cilia are non-motile (stereocilia).The cilia are non-motile (stereocilia).The epithelium rests on basement The epithelium rests on basement membrane surrounded by vascular membrane surrounded by vascular connective tissue containing smooth connective tissue containing smooth muscle fibers and elastic fibers.muscle fibers and elastic fibers.Its functins are absorption of the testicular Its functins are absorption of the testicular fluid, storage and maturation of the fluid, storage and maturation of the sperms and propulsion of the sperms sperms and propulsion of the sperms during ejaculation.during ejaculation.

Vas deferensVas deferensVas deferensVas deferensIt is a 45 cm tube with a narrow lumen and It is a 45 cm tube with a narrow lumen and thick muscular wall which is formed of:thick muscular wall which is formed of:

1.1. Mucosa: lined with pseudostratified ciliated Mucosa: lined with pseudostratified ciliated columnar epithelium and lamina propria rich in columnar epithelium and lamina propria rich in elastic fibers.elastic fibers.

2.2. Musculosa: inner and outer longitudinal layers Musculosa: inner and outer longitudinal layers and middle circular layer of smooth muscle and middle circular layer of smooth muscle fibers.fibers.

3.3. Adventitia: of loose connective tissue with Adventitia: of loose connective tissue with elastic fibers.elastic fibers.The muscle fibers contract forcibly during The muscle fibers contract forcibly during ejaculation of sperms.ejaculation of sperms.

It is a 45 cm tube with a narrow lumen and It is a 45 cm tube with a narrow lumen and thick muscular wall which is formed of:thick muscular wall which is formed of:

1.1. Mucosa: lined with pseudostratified ciliated Mucosa: lined with pseudostratified ciliated columnar epithelium and lamina propria rich in columnar epithelium and lamina propria rich in elastic fibers.elastic fibers.

2.2. Musculosa: inner and outer longitudinal layers Musculosa: inner and outer longitudinal layers and middle circular layer of smooth muscle and middle circular layer of smooth muscle fibers.fibers.

3.3. Adventitia: of loose connective tissue with Adventitia: of loose connective tissue with elastic fibers.elastic fibers.The muscle fibers contract forcibly during The muscle fibers contract forcibly during ejaculation of sperms.ejaculation of sperms.

Seminal VesicleSeminal VesicleSeminal VesicleSeminal VesicleThey are two highly coiled tubes (5-7 cm) They are two highly coiled tubes (5-7 cm) embedded in smooth muscle and connective embedded in smooth muscle and connective tissue.tissue.Each gland has three layers:Each gland has three layers:Mucosa: highly folded, lined by Mucosa: highly folded, lined by pseudostratified columnar epithelium and pseudostratified columnar epithelium and lamina propria of connective tissue containing lamina propria of connective tissue containing elastic fibers.elastic fibers.Musculosa: inner circular and outer Musculosa: inner circular and outer longitudinal.longitudinal.Adventitia: areolar connective tissue and Adventitia: areolar connective tissue and elastic fibers.elastic fibers.

They are two highly coiled tubes (5-7 cm) They are two highly coiled tubes (5-7 cm) embedded in smooth muscle and connective embedded in smooth muscle and connective tissue.tissue.Each gland has three layers:Each gland has three layers:Mucosa: highly folded, lined by Mucosa: highly folded, lined by pseudostratified columnar epithelium and pseudostratified columnar epithelium and lamina propria of connective tissue containing lamina propria of connective tissue containing elastic fibers.elastic fibers.Musculosa: inner circular and outer Musculosa: inner circular and outer longitudinal.longitudinal.Adventitia: areolar connective tissue and Adventitia: areolar connective tissue and elastic fibers.elastic fibers.

Function of Seminal VesicleFunction of Seminal VesicleFunction of Seminal VesicleFunction of Seminal VesicleIt secretes yellow viscous nutrient It secretes yellow viscous nutrient secretion containing: fructose, ascorbic secretion containing: fructose, ascorbic acid (vitamin C), citric acid and acid (vitamin C), citric acid and prostaglandins which:prostaglandins which:

1.1. Shares in formation of the fluid medium Shares in formation of the fluid medium of the semen.of the semen.

2.2. Important for the sperm metabolism and Important for the sperm metabolism and nutrition.nutrition.

3.3. Prostaglandins help in the effectiveness Prostaglandins help in the effectiveness of sperms inside the female reproductive of sperms inside the female reproductive tracts.tracts.

It secretes yellow viscous nutrient It secretes yellow viscous nutrient secretion containing: fructose, ascorbic secretion containing: fructose, ascorbic acid (vitamin C), citric acid and acid (vitamin C), citric acid and prostaglandins which:prostaglandins which:

1.1. Shares in formation of the fluid medium Shares in formation of the fluid medium of the semen.of the semen.

2.2. Important for the sperm metabolism and Important for the sperm metabolism and nutrition.nutrition.

3.3. Prostaglandins help in the effectiveness Prostaglandins help in the effectiveness of sperms inside the female reproductive of sperms inside the female reproductive tracts.tracts.