Male Reproductive System: Anatomy and Function

Posted on Apr 26, 2024 in Biology

Male Reproductive System

Testicles

  • Gonads
  • Located in the scrotum
  • Exo-endocrine gland

A-Exocrine gland:

  • Seminiferous tubules spermatogenesis ®
  • Genital tract and testis is Extratesticular

B-Endocrine Gland:

  • Interstitial cells secrete testosterone in a web of tissue between the seminiferous tubules

Role of body temperature:

  • Normal sperm production: 35°C
  • To accomplish this, the testicles are away from your body, encased scrotum

Pampiniform venous plexus:

  • Surrounding each testicular artery and help maintain low temperature in the scrotum

General organization:

1 – External Coverage:

  • Tunica albuginea: thick capsule of dense connective tissue
  • Tunica vaginalis: mesothelial serous sac, anterior and lateral surface covers testicular
  • The tunica albuginea is thickened on the back and form: mediastinum testis

2 – inside cover:

  • Tissue of the tunica albuginea into the parenchyma extensions start around 250 ® testicular lobules
  • Each is occupied by 1-4 seminiferous tubules
  • They are in a network of loose connective tissue, vessels, and nerves

Seminiferous Tubules:

A-Frame:

  • Sinusoidal Appearance
  • Fornix lead ®straight tubules rete testis ® ® ® epididymal efferent ducts

Its walls: 3 coats

Three layers:

1 – Tunic own:

  • Thin layer of tissue fibroelastic with several layers of fibroblasts
  • The innermost layer of the tunica propria myoid cells (characteristic of a smooth muscle myocyte)

Contractile movements of the tubules

2 – Basement membrane:

  • Separate the tunica propria of the seminiferous epithelium and germ

3 – germinal epithelium:

  • Two cell lines that give rise: sperm

1. Spermatogonia:

  • Small cell
  • Nucleus with irregular chromatin distribution
  • It is the only one present before puberty

Spermatogonia:

  • Divide:

A-similar to stem cell

B-cell to stop dividing and growing to form: spermatocytes 2

Intratesticular ducts:

A-tubules straight:

  • Home epithelium similar to that of the seminiferous tubules
  • Then the cells are lost until only a simple cuboidal epithelium

B-Red Testicular

  • Anastomosing tubules in the mediastinum testis
  • Upholstery: simple cuboidal epithelium or simple flat

C-tubules Efferent:

  • From 10 to 20 tubules
  • Measuring 4-6 mm
  • Its walls: smooth muscle
  • Upholstery: cubic epithelium ciliated columnar
  • Epithelium is capable of absorbing fluid secreted by seminiferous tubules
  • Penetrate the head region of the epididymis and flow: epididymal duct

Extratesticular or excretory ducts

A-Epididymis:

  • Length: 4-6 meters
  • This well run over on itself
  • Pseudostratified cylindrical epithelium at the apical: microvilli

B-Vas Deferens:

  • Thick-walled straight tube
  • Light: close
  • Thick wall: smooth muscle
  • Its mucosa has many folds
  • Mucosa upholstered: pseudostratified ciliated columnar epithelium
  • Lamina propria: connective tissue rich in elastic fibers
  • Muscle layer: highly developed smooth muscle
  • 2 longitudinal layers: internal and external, 1 circular middle layer
      • Adventitia: connective tissue
  • In the terminal portion before entering the prostate, it expands and forms: Blister
  • In the terminal region of the ampulla, seminal vesicle empties

Ejaculatory duct:

  • Short tube upholstery: pseudostratified columnar epithelium
  • You lose the muscle layer

Urethra:

Genitourinary Tube

A-seminal vesicle:

  • They are 2 each: tube 15 cm long coiled upon itself
  • Mucosa: epithelium lined by simple cuboidal or low cylindrical pseudostratified
  • This mucosa is highly folded
  • Cells: rich granules are secretory proteins, fructose, citrate, inositol, prostaglandins
  • Lamina propria: rich in elastic fibers
  • Muscle: smooth muscle
    • Inner layer of circular fibers
    • Outer layer of longitudinal fibers
  • Its secretion builds up inside and is eliminated in the ejaculation by contracting the smooth muscle fibers

B-Prostate Gland:

  • It surrounds the urethra below its origin bladder
  • Composite: 30 – 50 tubulosaccular glands, branched flow: prostatic urethra

Produce: prostatic fluid and store it inside.

  • Upholstered: simple cuboidal epithelium or pseudostratified cylindrical
  • Secretor: protein
  • The epithelium on the inside has a large number of lysosomes, with intense activity: acid phosphatase
  • Important determinant of cancer cases
  • Three areas:

1-Central: pseudostratified epithelium, glandular volume occupies 25%

2 – Peripheral: main site in the development of malignant tumors

3 – Transition: small, site of origin of benign

  • At the peripheral level:
    • Fibroelastic tissue capsule
    • Smooth muscle contracted during ejaculation
  • This capsule form walls.

Bulbourethral glands or cowpers

  • Peers
  • Tubulosaccular glands located behind the membranous urethra
  • Cells: mucous type
  • Partitions divide: smooth and skeletal muscle

Mucosa: simple cuboidal epithelium.

Penis

Organization:

  • Three bodies of erectile tissue, spongy tissue surrounded by + urethra
  • Externally wrapped by thin skin
  • Two mass numbers: corpus cavernosum
    • Ventral mass: corpus cavernosum of the urethra
  • The 2 bodies of the penis are surrounded: tunica albuginea of the penis
  • TA forms a strong membrane of dense connective tissue that is inserted between 2 corpus cavernosum
  • This wall is not continuous septa
  • The corpus cavernosum of the urethra: is enclosed in a thin

connective tissue

Erectile tissue:

  • It forms an irregular network around each body
  • This comprises: fibrous tissue forming trabeculae and that also contains smooth muscle fibers

Blood supply: S.

  • It depends on the functional status:

A-State flaccid: dorsal peripheral arteries, immersed in the loose connective tissue ® arterial blood supply

Drainage of venous blood:

  • Two dorsal veins: superficial and deep

In flaccid state, the AV shunts between arteries deep and superficial veins are open.

B-erect state:

  • AV shunts are closed
  • Innervation:
    • Parasympathetic stimulation: erection
    • The sympathetic contribution: ejaculation

Foreskin:

  • Contains: connective tissue, skin, smooth muscle
  • Features retractable
  • Regarding its inner fold and the area of skin over the glans note: sebaceous glands


Immune System

  • Reticular connective tissue where most of the cells represent lymphocytes

Primary (LB-LT)

  • Lymphoid Organs

Secondary (lymph nodes, spleen, MALT)

RXS occur in these immune.

  • Lymphoid organs: primary and secondary
  • Clusters of lymphoid tissue in non-lymphoid organs
  • Lymphocytes scattered in TC and TE
  • Lymphocytes, stem cells, plasma cells, macrophages, dendritic cells, granular leukocytes, and mast cells
  • Mean insensitivity to infection

Congenital skin, stomach acid

  • 2 types: phagocytosis and inflammation

Acquired antibodies

  • Specific defensive Rx Immune Response
  • Tolerance: no rx immune to the components of the body
  • Memory

TYPES OF IMMUNITY

Two Types:

  • Mobile: made by T lymphocytes that eliminate the sustuncias directly or by activation of phagocytes
  • Humoral: using antibodies (globulins) produced by plasma cells circulating formed from B lymphocytes.

Lymphatic Organs

TIMO

  • Primary lymphoid organs
  • Site of maturation of LT
  • It is located in the anterior mediastinum
  • It weighs 50 grams and regresses at puberty
  • Composed by 2 lobes
  • It originates from ectodermal and endodermal epithelium branchial groove 3 in the 6 weeks
  • It is surrounded by CT capsule septa toward issuing corticomedullary boundary divides the lobes into lobules
  • The lobules are polyhedral and measure 0.5-2mm in diameter
  • It has a darker area and rich in cells called the cortex and a lighter and less marrow cell called
  • It has a loose stroma composed of epithelial reticular cells form a network among which are lymphocytes, macrophages, and dendritic cells
  • Reticular cell has abundant eosinophilic cytoplasm and large clear oval nuclei with 1 or 2 nucleoli, and star-shaped extensions interdigitating with each other
  • Cortical reticular cells originate from the endoderm and the medullary and subcapsular reticular (premium) from the ectoderm
  • The bone has Hassall corpuscles are round or oval structures composed of concentric layers of flattened epithelial cells similar to onion rings with a size of 20-100 microns and increases with age
  • Are most abundant in bone marrow macrophages
  • Dendritic cells are found mostly in the corticomedullary boundary
  • At the heart have long extensions in contact with lymphocytes and, like the lattice involved in the maturation of lymphocytes
  • As involution progresses appears larger amount of adipose tissue replacing the parenchyma

LYMPH NODES

  • Secondary lymphoid organs brought flattened kidney-shaped in the course of lymphatic pathways
  • Their size varies from a few mm to 2 cm
  • Surrounded by dense CT capsule that sends projections to the interior trabecular
  • Presents a hilum on one edge where the capsule is thicker
  • It has several afferent lymphatic vessels
  • Presents a single efferent vessel present in the porta
  • It is divided into a central area called the medulla and a cortex
  • In the cortex are formed follicles (nodules)
  • The stroma is composed of fibers and reticular cells
  • Interdigitating dendritic cells are located in the deep crust and in the hair follicle of the cortex (the latter have no antigen)
  • Subcapsular sinus between the cortex and capsule
  • Cortical sinuses along the trabeculae
  • Medullary sinuses medullary cords separated

SPLEEN

  • Secondary lymphoid organ located in abdominal CSI
  • Weight 150-200 g and measuring 4x8x12 cm
  • Brought into the bloodstream
  • Surrounded by dense CT capsule with few smooth muscle fibers from which trabeculae extend into the
  • It has only efferent lymphatic pathways
  • It originates from the dorsal mesogastrium mesenchyme during the 5 wk
  • Serves as erythropoietic organ during the second trimester of pregnancy
  • Hilar region presents oriented stomach
  • The marginal zone is the area constraint between the red and white pulp
  • The parenchyma is called pulp

Red: irregular thin-walled vessels

(Sinusoidal) splenic cords separated by

  • Pulp

White: oval or rounded areas

gray or white, 1 mm

diameter composed of lymphoid tissue

diffuse or follicular (Malpighian corpuscle)

TONSILS

  • Clusters of lymphoid tissue that are located in the path of lymph vessels.
  • There are three:
    • Palatine
    • Pharyngeal

Lingual.

  • Oropharynx
  • Lymphoid tissue is organized into nodules covered by a surface epithelium: oropharynx, which invaginates: 10 to 20 times to form the crypts
  • Featuring tej thickening posteriorly. disorders: which separates them from deep levels

Pharyngeal:

  • Lymphoid tissue: lymph covered by respiratory epithelium, with absence of crypts.

Tongue:

  • Numerous
  • Located at the base of the tongue
  • Lymphoid tissue: lymph
  • His mucosal crypts invaginates and forms

OJO

  • Photosensitive bodies
  • Refractory structures: cornea, lens
  • Visual information is transmitted: the optic nerve to brain
  • Eyeball:
  • A-fibrous tunic
  • B-Vascular
  • C-Nerve

A-fibrous tunic:

  • Outer:

1 – Sclera (whites)

2 – Cornea.

1-Sclera:

  • White coat
  • Opaque
  • Covers 5 / 6 following

2 – Cornea:

  • Clear and colorless
  • Cover 1 / 6 previous

Sclera:

  • Poor blood vessel
  • Composite:
  • Fibrous connective tissue, collagen I and elastic fiber networks
  • In deeper regions: melanocytes

Cornea:

  • Anterior
  • Transparent
  • Avascular
  • Very innervated
  • Slightly thicker than the sclera

Histological layers composed 5.

1 – corneal epithelium:

  • Continuation of the conjunctiva
  • Keratinized stratified squamous epithelium
  • 5 to 7 layers of cells in the anterior surface of the cornea
  • More superficial cells have microvilli ® zonulae occludens
  • The remaining cells are joined by desmosomes
  • Free nerve endings innervated
  • More superficial cells have microvilli ® zonulae occludens
  • The remaining cells are joined by desmosomes
  • Free nerve endings innervated
  • Union: scleral-corneal: limbo ® a groove whose spaces are lined by endothelial trabecular meshwork
  • This network gives rise: canal of Schlemm: site through which aqueous humor leaves the anterior chamber into the venous system

4 – Descemet membrane:

  • Basal
  • Gross
  • At birth and in young people: thin
  • Aging thick

5 – corneal endothelium:

  • Inner surface: horny
  • Synthesize: Descemet membrane proteins
  • Reabsorbed sodium bomb excess fluid in the stroma

Tunic B-vascular:

  • Tunica media [uvea]
  • Three components:
    • Choroid
    • Ciliary body
    • Iris

A-Choroid:

  • Pigmented
  • Very vascular
  • Loosely attached to the fibrous
  • Composes: TCL, collagen fibers, elastic vessels
  • Black: melanocyte
  • Inner choriocapillaris layer: provides the nutrients to the retina
  • Bruch Membrane: elastic fiber network
  • Separate: choroid retina

B-ciliary body:

  • Extension of the choroid
  • Ciliary processes: short projections of the body towards the lens
  • Composite: TCL, elastic fibers, blood vessels and many melanocytes
  • Inner surface is covered: pigmented layer: epithelium.
  • In this body are fenestrated capillaries
  • The ciliary processes that send fibers are inserted into the lens capsule: suspensory ligament of lens
  • Find: non-pigmented epithelium: ultrafiltrate produced plasma: aqueous humor
  • The main volume of the ciliary body is composed of: 2 bundles of smooth muscle: ciliary muscle

A beam is inserted into the sclera, the other along the inner wall of the body.

C-Iris:

  • Most anterior extension of the choroid
  • It covers most of the lens, except at the pupil
  • Posterior surface is smooth: Covered in layers of the ciliary body
  • Epithelial cells facing the stroma of the iris have extensions: m pupil dilator: myoepithelial nature
  • The melanocytes of the iris blocking passage of light and give the eye color

Lens:

  • Transparent
  • Flexible
  • Biconvex
  • Composed of epithelial cells
  • Consists of 3 parts:

1 – Capsule: basal lamina, collagen IV and glycoproteins that cover epithelial cells

2 – subcapsular epithelium: single-level anterior surface, single layer of cuboidal cells: gap-junction

3 – lens fibers: about 2000 cells long, they lose their nucleus and are filled with protein.

Vitreous Body: (vitreous humor)

  • Refractive Gel
  • Transparent
  • Fill the cavity of the eye behind the lens
  • 90% water, few electrolytes, collagen fibers and hyaluronic acid

C-nerve Tunic (Retina):

  • Photoreceptor cells: rods and cones
  • Differentiated cells of the brain are
  • Optical Disk
  • Optical Disk:
  • It is located in the posterior wall of the eye
    • At the exit of the optic nerve
    • Absence: cone-rod
    • It is insensitive to light: blind spot
    • A + / – 2mm: macula lutea: pigment area
  • In the middle of it we have an oval depression: central fovea
  • Peak visual acuity: single cones
  • As we move away from her, the rods and cones decrease increase

Retina: 10-layer composite:

1 – pigment epithelium:

  • Cubic to cylindrical
  • Nucleus basalis
  • Posted in Bruch’s membrane (between the choroid and pigment cells)
  • Desmosomes, occludents, acceding form: blood-retinal barrier
  • Have microvilli on their apices surrounding rods and cones
  • Cells have many melanin granules synthesized by them
  • Rer, A. Well-developed Golgi
  • Features: absorb light, phagocytosis and esterified derivatives of Vit. A in REL

2 – Layer Rods and Cones:

  • Their apical portions: specialized dendrites
  • Their bases: neighboring cell synapse

100 to 120 million rods and 6 million cones.

Canes:

  • Light to activate light: black and white
  • They are long cells have:
    • 1 outer and inner segment
    • Nuclear region

Synaptic region.

Cones:

  • Are active in bright light
  • Produce greater visual acuity

It is the vision of colors.

  • The rod-like structure
  • There are 3 types of cones: each has a different variety of rhodopsin:
  • Sensitivity: red, green, blue
  • The rod-like structure

4 – outer nuclear layer:

  • Mainly occupied by nuclei of cone-rod

5 – outer plexiform layer:

  • Axodendríticas synapses between photoreceptor cells and other neurons

6 – inner nuclear layer:

  • Nuclei formed by bipolar cells, amacrine, horizontal and Muller

7 – inner plexiform layer:

  • Synapse axodendríticas
  • Among the bipolar cell axons and dendrites of ganglion cells

8 – ganglion cell layer:

  • Multipolar cell bodies of neurons
  • Hyperpolarization activated rod and cone cells ®
  • It generates an action potential to be amacrine and horizontal cells, and finally to the brain

9 – optic nerve fiber layer:

  • Unmyelinated axons of ganglion cells

10 – internal limiting membrane:

  • Cell basal lamina muller

ANNEXES TO THE EYE

A-Conjunctiva:

  • Stratified epithelium
  • Goblet cells resting on a basal lamina and a proper TCL
  • Two types: palpebral and bulbar

B-Lids:

  • Skin folds

C-Lacrimal Apparatus:

  • Lacrimal gland
  • Serosa tubuloalveolar
  • Resembling the parotid
  • The tear fluid: sterile
  • High% water and lysozyme
  • Help to keep moist and hydrated to the sclera and cornea
  • Travel through a system of lacrimal canaliculi
  • Lined by stratified squamous epithelium
  • Lacrimal sac: dilated upper portion of the nasolacrimal duct
  • This upholstery: pseudostratified ciliated columnar epithelium
  • The follow below: Nasolacrimal
  • It has the same epithelium

Ear

Vestibulo cochlear

  • Body: hearing and balance
  • It is divided into 3 parts:

1 – External ear

2 – Middle ear: tympanic cavity

3 – Inner ear

The sound wave is received by the outer ear ? reaches the tympanic membrane mechanical vibrations ?

  • In middle ear ossicles tympanic cavity ?
  • The cacidad amplifies the vibrations and transfer them to the inner ear
  • This is a labyrinth full of perilymph which is responsible for hearing and balance conservation

Ear

  • External
  • Average
  • Internal

External:

  • Pinna
    • Ear canal

Media:

  • Tympanic cavity
    • Tympanic membrane
    • Eustachian tube
    • Mastoid antrum
    • Mastoid cells
    • Tympanic cavity (hammer, anvil, stirrup, stirrup muscle and muscle from the hammer)

Internal:

  • Maze (in the petrous bone)
    • External Labyrinth
    • Membranous labyrinth
    • Endolymph
    • Perilymph
  • The bony labyrinth communicates with the tympanic cavity by ½ of the oval window
  • Oval window:
    • It closes with the base of the stapes (transmitting the vibrations of the ossicles to the perilymph)
    • Also with the cochlear window which closes with the secondary tympanic membrane

EXTERNAL EAR

Ear elastic cartilage plate, covered by skin

External auditory meatus:

  • Superficial: elastic cartilage that is continuous with the ear
  • In its 2 / 3 is replaced by the internal temporal bone: bra
  • Covered: skin, hair, Gland tympanic membrane:
  • Outer surface: epidermis thin
  • Inner surface: squamous epithelium simple cubic
  • Between the two surfaces are elastic collagen fibers, fibroblasts
  • Sound waves are received by ½ of it (vibrate)
  • ulas modified sebaceous sudorápadas: ceruminous: cerumen

MIDDLE EAR

  • Space filled with air, which is located in the petrous temporal bone
  • Covering: simple squamous epithelium
  • In the area around the auditory tube: ciliated pseudostratified
  • Lamina propria was strongly attached to the bony wall of the trunk and contains no glands,
  • At the level of the cartilaginous portion of the lamina propria it contains mucous glands with goblet cells and lymphoid tissue
  • Swallowing or yawning trunk make the hole to open and equalize air pressure between the tympanic cavity, auditory meatus

Oval and round window:

  • They are located in the medial wall of tympanic cavity
  • Connect the middle ear cavity to the inner ear

Are membranes.

Ossicles:

  • Hammer, anvil, stirrup
  • Articulated by synovial lined by simple squamous epithelium
  • Hammer: tympanic membrane inserted
  • Stirrup: inserted into the oval window
  • Yunque: interposed between the two previous

INNER EAR

Composite:

  • Bony labyrinth: cavity within the petrous temporal bone
  • Membranous labyrinth: suspended within the bony labyrinth

Bony labyrinth:

  • Three components:
    • Semicircular canals
    • Lobby
    • Cochlea
  • Investing: endosteum
  • Separated by membranous labyrinth perilymphatic space (the full perilymph)

Its central region: vestibule.

  • Semicircular canals: three superior, posterior and lateral
  • Lobby: it is central
  • In its side wall contains the oval window and round or cochlear
    • Houses: special regions: the utricle and saccule
  • Snail-shaped bony structure of spiral
  • At the central level ? ? modiolus central bony spine

Membranous labyrinth:

  • Composed of epithelium derived from ectoderm
  • This epithelium invades the temporal bone and form 2 sacks: utricle, and saccule
  • In endolymph circulates around the maze (composition similar to the SCI)

Membranous labyrinth:

  • There are thin bands of tissue attached to the endosteum of the bony labyrinth
  • These bands passing through the endolymph and inserted into the membranous labyrinth
  • Important to carry blood vessels that nourish the lining of the membranous labyrinth

Membranous labyrinth:

  • Saccule and utricle:
    • It is connected by duct utrículosacular
    • From each tiny tubes out: endolymphatic duct

Saccule walls – utricle:

  • External: vascular tissue layer
  • Internal: simple squamous epithelium simple cuboidal
  • Specialized regions act as receptors that perceive the orientation of the head relative to gravity and acceleration: macula utricle saccule and macula

Saccule walls – utricle:

  • The epithelium of recipient regions: light and dark cells
    • Clear cells: microvilli, cytoplasm, ribosomes and few mitochondria
    • Dark cells: abundant vesicles, lipid droplets, many mitochondria, are thought to control the composition of endolymph
  • Macules: composed of 2 types of neuroepithelial cells:
    • Hair cells type I, II
    • Supporting cells
  • Hair cells are innervated by auditory nerve fibers
  • Each of them has: 50-100 stereocilia in a row

Type I hair cells:

  • Cytoplasm little RER, golgi supranuclear and many small vesicles
  • Each esterocilio is a microvillus with many actin filaments

Type II hair cells:

  • Similar to Type I
  • More cylindrical
  • Cytoplasm, Golgi apparatus and more larger vesicles

Supporting cells of the macula:

  • Interposed between both hair cells
  • They have microvilli

Developed Golgi.

  • The stereocilia of hair cells are covered by a dense glycoprotein ? gelatinous otolithic membrane
  • The surface of this membrane region has tiny crystals of calcium carbonate otoliths

Semicircular canals:

  • Below are the membranous labyrinth
  • Each duct is dilated at the lateral end ? blisters
  • The blisters contain ampullary crests: special reception areas
  • Each peak level of his lip has a free surface covered: sensory epithelium
  • Formed: neuroepithelial hair cells and supporting cells

Cochlear duct and organ of Corti:

Cochlear duct:

  • Receptor organ that is housed in the cochlea
  • Contains:
    • Scala media
    • Vestibular membrane
    • Basilar membrane
  • Scala vestibuli
    • Located above the vestibular membrane
    • Full perilymph
  • Scala tympani
    • Find below the basilar membrane
    • Filled with perilymph
  • Vestibular membrane:
    • Composed of 2 layers of simple squamous epithelium separated by a basal lamina
  • Basilar membrane:
    • Holds the organ of Corti
    • Composed of 2 parts: curved and dentate

The arch provides support to the organ of Corti.

  • The side wall covered by a pseudostratified epithelium
  • Stria vascularis contained inside an intraepithelial plexus capillaries
  • Composes 3 types of cells:
    • Basal
    • Intermediate

Marginal.

ORGAN OF CORTI.

  • Receiving organ specialized in hearing
  • It lies on the basilar membrane
  • It is composed of neuroepithelial hair cells and supporting cells
  • These cells are pillar cells, phalangeal, edge and those of Hensen

Neuroepithelial cells of the organ or Corti hairy:

  • Specialize in the transduction of the impulses to the organ of hearing
  • According to their locations are called hairy: internal and external
  • This system is located in the vestibular inner ear
  • Consisting of utricle, saccule and semicircular canals
  • The linear movement of the head moves the endolymph, and alters the location of the otoliths

Vestibular function:

  • Produce movements in the stereocilia of hair cells
  • These are translated into action potentials that are driven by acoustic nerve synapses to the mite and to the brain
  • The circular movements: they are perceived by receptors at the level of bony semicircular canals

Vestibular function:

  • The information related to linear and circular movements of the head is recognized by receptors of the inner ear and are transmitted to the brain via the auditory nerve
  • Within the brain to produce the interpretation and balance adjustments occur through the activation of muscle groups responsible for the position