Begins at puberty Reduces ploidy & chrom number Spermatocytogenesis- undiff spermatogonia beomes spermatogonia: Type A spermatogonia: Type A dark: A= type Ad or Type Ap Type A pale= type B spermatogonia Type B speratogonia=type B spermatogonia or primary spermatocytes Meiotic divisions- allow primary spermatocytes to become spermatids spermiogenesis- morphological diff of spermatids into mature sperm(atozoa)

Male Reproductive System Flashcards by Esty Sherman

Tunica Vaginalis

2 layers:

outer parietal layer

inner viscera layer

How well did you know this?

Not at all

Perfectly

Tunica albuginea

Directly on the testes

Dense CT

Form fibrous septa that divide testes into 250-300 pyramidal compartments called lobules

How well did you know this?

Not at all

Perfectly

Lobule

1-4 seminiferous tubules (produce spermatozoa)

loose CT

nerves

blood & lymph

endocrine interstitial cells (Leydig cells)

How well did you know this?

Not at all

Perfectly

Sperm Pathway

seminiferous tubules–> straight tubule–> rete testis–> 10-20 efferent ductules that connect to head of epididymis (head, body, tail)

How well did you know this?

Not at all

Perfectly

Seminiferous tubules

250-1000 per testicle

200 million per day in adult male

Older in the center/lumen

How well did you know this?

Not at all

Perfectly

Leydig cells

interstitial cells

secrete testicular androgens *testosterone

How well did you know this?

Not at all

Perfectly

Spermatogenesis

Begins at puberty

Reduces ploidy & chrom number

Spermatocytogenesis- undiff spermatogonia beomes spermatogonia:

Type A spermatogonia:
Type A dark: A= type Ad or Type Ap
Type A pale= type B spermatogonia
Type B speratogonia=type B spermatogonia or primary spermatocytes

Meiotic divisions- allow primary spermatocytes to become spermatids

spermiogenesis- morphological diff of spermatids into mature sperm(atozoa)

How well did you know this?

Not at all

Perfectly

Spermatogenesis continued

How well did you know this?

Not at all

Perfectly

Spermiogensis

Transform round spermatids into elongated, free swimming spermatozoa capable of fertilization

4 phase: Golgi, Cap, Acrosome & maturation

How well did you know this?

Not at all

Perfectly

Golgi Phase

first polarity

prominent golgi apparatus w/ proacrosomal granules to become acrosomal cap

How well did you know this?

Not at all

Perfectly

Cap Phase

acrosome cap enlarges, then flattens & extends over the nucleus.

Acrosome is specialized lysosome, containing hydrolytic enz capable of dissociating the corona radiata & zona pellucida of oocyte

1 centriole acts to organize initiation of a flagellum

How well did you know this?

Not at all

Perfectly

Acrosomal Phase

spermatids become oriented toward basement mem

nuclei become more elongated chromatin becomes more condensed

head cap begins to move toward tail

flagella continue to grow

Manchette= contains motor proteins!

How well did you know this?

Not at all

Perfectly

Maturation Phase

Unneeded cytoplasm is shed as residual body

Mature sperm are released into lumen of seminiferous tubule

How well did you know this?

Not at all

Perfectly

Spermiogenesis Histo

Myoid Cell= contracts to expel sperm into lumen

Spermatocytes largest more numerous cells in seminiferous tubule, have condensed chrom

How well did you know this?

Not at all

Perfectly

Sertoli Cells

Columnar or pyramidal cells- base adheres to basal lamina

Apex extends into lumen of seminiferous tubule

Envelop spermatogenic cells

connected to ea other by numerous gap junctions

F as supporting (nurse) cells- ea contains 30-50 germ cells @ various stages of development

How well did you know this?

Not at all

Perfectly

Function of Sertoli Cells

support, protection, & nutrition of developing spermatogenic cells- because spermatocytes, spermatids & spermatozoa are isolated from blood supply by blood testis barrier, these cells depend on Sertoli cells to mediate nutrient & metabolite exchange
exocrine- nutrients & androgen binding protein (ABP) which concentrates testosterone to a level required for spermiogenesis (promoted by FSH)
Endocrine- secretion of inhibin & MIS (mullerian inhibiting substance)
phagocytosis- residual bodies (cytoplasm) from spermiogenic cells is phagocytosed

Blood Testis Barrier

physical barrier between blood vessles & seminiferous tubule

formed b/t sertoli cells (tight junctions)

separates seminiferous tubule into a basal compartment & adluminal compartment

Prevents passage of cytotoxic agents into seminiferous tubules

*during spermatogenesis, cells after division squeeze through & transverse junctions to lie in adluminal compartment (above barrier)

Interstitial Tissue & Leydig Cells

Interstitial tissue- site of androgen production, CT containing mast cells, macrophages, n., lymphatics & blood vessels

Leydig cells- become apparent @ puberty, produce testosterone (stim by LH, important for male repro dev & spermatogensis)

Intratesticular Ducts

Straight tubules–> Rete testis–>Efferent ductules

carry spermatozoa & liquid from seminiferous tubules to duts of epididymis

Seminiferous tubules= arranged as loops, both ends join rete testis

Straigh tubules= char by gradual loss of spermatogenic cells, has initial seg of walls lined only by Sertoli cells, main seg is cuboidal epith supported by dense CT

Rete testis= interconnected network of channels lined by cuboidal epithelium

Efferent Ductules

15-20

lined by nonciliated cuboidal cells alternating w/ groups of taller ciliared cells

non ciliated= absorb most of fluid secreted by seminif tubules

ciliated= beat in direction of epididymus

Excretory Gential Ducts

Epididymis

Ductus (vas) deferens

Urethra

Accessory glands secrete into these

Essential for reproductive function

Ductus Epididymis

Single highly coiled tube

Forms head, body & tail

Sperm stored here & attain their final char including motility, mem R for zona pellucida proteins, maturation of acrosome & ability to fertilize

Ductus/Vas Deferens

long straight tube w/ thick muscular wall

Has narrow lumen & thick smooth m. (longitudinal outer & inner layers w/ middle circular layer)

mucosa folded longitudinally & is lined by pseudostratified columnar epithelium w/ sparse stereocilia

Pathway

Ductus deferens–> passes over urinary bladder–> then dilates to form ampulla (epith thick & more folded)–> at distal end of ampulla, seminal vesicles join the duct–> ductus deferens enter the prostate gland (as ejaculatory duct) & open into prostatic urethra

Vasectomy

Ductus deferens is part of spermatic cord- testicular a., pampiniform plexus, nerves 1-2 small openings in scrotum. Vas deferens cut- ends ligated (vasclip= no cutting) Testes produce sperm but die & reabsorbed sperm! Permanent though reversal available

Accessory Gland

produce secretions that are added to sperm during ejaculation to produce sperm, essential for reproduction. Seminal vesicles Prostate gland Bulbourethral glands

Seminal Vesicles

Highly Tortuous tubues Exocrine glands- produce viscid, yellow secretion (w/ fructose, citrate, inositol, PGs, fibrinogen, enzymes & other proteins) 70% of ejaculate Simple/pseudostratified columnar eptih that are rich in secretory granules lamina propria contain elastic fibers surrounded by smooth m. cells (inner circular, outer longitudinal)

Prostate Gland

Surrounds urethra, inf to bladder 30-50 branched tubuloalveolar glands Inner to outer around urethra: * transitional zone- 5% mucosal glands * central zone- 25% submucosal glands * peripheral zone- 70% main glands

Tubolalveolar glands

-cuboidal or pseudostratified columnar epith. Rich fibromuscular stroma surrounds the glands. ## Footnote Glands produce prostatic fluid- contains various glycoprotein & enz that are expulsed during ejaculation

Corpora amylacea

small spherical concretions formed in lumen of prostatic glands Number increase w/ age but no signif

Benign Prostatic Hyperplasia

Enlargement of prostate due to increase in cell number- prostatic stromal & eptih cells non malignant Starts in 30s, 50% in men over 50 & 75% in over 80 yo Urinary storage & voiding problems Give DH2 5 a reductase inhibitor

Prostate Cancer

most common cause of death from cancer in men over 75 No symptoms until later stages. Use Gleason scale!

Bulbourethral Gland

Paired round gland Several lobules w/ tubuloalveolar secretory units lined by simple columnar epith w/ mucus secretion (depends on testosterone) Septa b/t lobules contains smooth m.- release mucus secretion which cotas urethra for ejaculation preparation Empties into penis

Penis

3 cylindrical masses of erectile tissue & penile urethra surrounded by skin: 2 dorsal corpora cavernosa- tunica albuginea 1 ventral corpus spongiosum- surrounds urethra Penile urethra- mostly pseudostratified columnar epith at glans penis= stratified squamous epith!

Arteries of Penis

Derived from internal pudendal arteries= dorsal arteries, deep arteries (nutritive a.- trabeculae) & helicine arteries (to cavernous spaces)

Penile Erection

Filling of cavernous spaces with blood ANS to smooth m. in vascular walls point & shoot! Parasym= m. relaxation in trabeculae & dilation of helicine arteries--\> filled space compresses veins against tunica albuginea (block outflow of blood)--\> rigidity of cylindrical erectile tissue Symp= ejaculation--\> constrict helicine arteris (decrease blood flow into spaces)--\> pressure is decreased--\> veins are allowed to open--\> drainage of blood from erectile tissue