Internal organs Flashcards
Ureter
Retroperitoneal
Renal artery
Tunica adventitia-blood vessels, loose CT, adipose tissue, nerves
Conducts urine from renal pelvis to urinary bladder
24-34cm
Lamina mucosa- transitional epithelium
Lamina propria- dense CT
Tunica muscularis - inner longitudinal, middle circular, outer longitudinal
Urinary bladder
Located in pelvis behind pubic symphysis
Tunica mucosa- lamina epithelium - transitional
Lamina propria- - loose CT
Sympathetic nerve supply - hypogastric plexus
Parasympathetic - pelvic splanchic nerve
Internal urethral sphinctor has 3 openings - 2 for ureter and 1 for urethra
Hollow muscular organ
Smooth muscle of bladder wall
Detrusor muscle - contraction compresses the entire organ and forces urine into urethra
Tunica serosa - loose CT covers superior surface of bladder
Urethra in males
Fibromuscular tube
Serves as the terminal duct for both the urinary and genital systems
20cm long
Prostatic urethra -extends from the neck of the bladder through the prostate gland. Lined with transitional epithelium.
Membraneous urethra - extends from the apex of the prostate gland to the bulb of the penis
Penile urethra - extends from about 15cm through the length of the penis and opens on the body surface at the glans penis
Lined with pseudostratified epithelium
Lined with stratified squamous epithelium at its distal end
Ducts of Cowper’s glands and glands of Lifted empty into penile urethra
Urethra in females
3-5cm long
It’s mucosa has longitudinal folds
Lined with transitional epithelium, but stratified squamous before its termination
Urethral glands open into the urethral lumen
Testis
Suspended by spermatic cords
Connected to the scrotum by scrotal ligaments
When descending from the abdominal cavity, into the scrotum they carry with them:
Blood vessels
Lymphatic vessels
Autonomic nerves
Tunica vaginalis - extension of the abdominal peritoneum.
Tunica albuginea:
A CT capsule that covers each testis
Tunica vasculosa:
Inner part of tunica albuginea
Loose CT layer and contains blood vessels
Each testis is divided into 250 lobules by incomplete CT septa.
Each lobule consists of 1-4 seminiferous tubules in which sperm are produced.
Has CT stroma in which leydig cells are.
Consists of seminiferous epithelium surrounded by a tunica propria.
Complex stratified epithelium, containing 2 cells: sertoli cells and spermatogenic cells.
Epididymis
Crescent shaped
Lies along superior and inferior surfaces of the testis
Consists of efferent ductules and the duct of the epididymis and associated vessels, smooth muscle and CT coverings
Divided into:
Head - efferent ductules
Body
Tail - both duct of epididymis
Duct of epididymis is lined with pseudostratified columnar epithelium.
Contains: principle cells and basal cells.
Seminal duct
A tube serving as an efferent duct of the testis Made up of the tubules of the: Epididymis Vas deferens Ejaculatory duct
Vas deferens:
A direct continuation of the tail of the epididymis
Enters the abdomen and passes through the inguinal canal as a component of the spermatic cord
After leaving the spermatic cord, it descends in the pelvis to the level of thebladder, where its distal end enlarges to form the ampulla
Lined with pseudostratified columnar epithelium
Columnar cells with microvilli
Rounded basal cells rest on basal lamina.
Spermatic cord
Formed by the vas deferens and surrounding tissue that run from the inguinal ring down to each testicle
Ensheathed in 3 layers:
External spermatic fascia
Cremasteric muscle and fascia
Internal spermatic fascia
Contains:
Testicular artery
Deferential artery
Cremasteric artery
Nerves:
Genital branch of the genitofemoral nerve
Sympathetic nerves
Ilio-inguinal nerve
Seminal vesicle
Paired, highly folded tubular glands
Located on posterior wall of bladder.
It’s wall contains:
A mucosa
A layer of smooth muscle
A fibrous coat
Pseudostratified columnar epithelium has columnar cells - secretions are whitish yellow
Prostate
Largest accessory sex gland of males
Located in pelvis, inferior to bladder
Consists of 30-50 tubuloalveolar glands arranged in 3 concentric layers:
Inner mucosal layer
Intermediate submucosal layer
Peripheral layer
Peripheral layer contains main prostatic glands
Glands of the mucosal layer secrete into the urethra
Zones of the adult prostatic parenchyma:
Peripheral zone
Central zone
Transitional zone
Periurethral zone - contains mucosal and submucosal glands
Parenchymal epithelium is simple columnar
Smooth muscle in the stroma.
Bulbo-urethral gland
Paired, pea-sized structures
Located in urogenital diaphragm
The duct of each gland passes through the inferior fascia of the urogenital diaphragm and joins the initial portion of the penile urethra
Composed of the tubulo-alveolar glands
Penis
Has a root: made upnof the bulb and the right and left crura
Has a body: consists of the 3 cylinders of erectile tissue enclosed in a tubular sheath of fascia:
2 dorsal masses (corpus cavernosa)
A ventral mass (corpus spongiosum) - spongy part of urethra is embedded
Tunica albuginea:
Dense, fibroelastic layer
Bindsnthe 3 cylinders together and forms a capsule around each one
Corpora cavernose: Contains vascular spaces Lined with vascular endothelium Surrounded by a layer of smooth muscle that forms trabeculae within tunica albuginea Derived from helicine arteries
It’s skin:
Thin loosely attached to underlying CT, very think and tightly attached to the glans
The prepuce - fold of skin that covers glans
Sebaceous glands - in the skin of the penis, just proximal to the glans
Transitional epithelium - lines prostatic part of urethra
Pseudostratified to stratified columnar epithelium - lines the membranous and spongy portions
Stratified squamous in spongy urethra - has goblet and intraepithelial glands.
Scrotum
A dual chambered proturbance of skin and muscle - contains testicles.
Divided by septum
Anterior scrotal artery and posterior scrotal artery. Testicular vein.
Innervation: Posterior scrotal nerves Anterior scrotal nerves Genital branch of genitofemoral nerve Perineal branches of posterior femoral cutaneous nerve.
Superficial inguinal lymph nodes - keep temp of body slightly lower than the rest of the body
Superficial fascia - has smooth muscle
Spermatic fascia - derived from 3 layers of anterior abdominal wall: external spermatic fascia
Cremasteric fascia
Internal spermatic fascia
Tunica vaginalis - lies within the 3 spermatic fascia, a closed sac
Uterine tube
Paired tubes
Transport the ovum from the ovary to the uterus
Provide the environment for the fertilisation and initial development of zygote to the morula stage
Segments:
The infundibulum - funnel shaped segment
The ampulla - longest segment of the tube, site of fertilisation
The isthmus - narrow segment
The uterine part - lies within uterine wall
Opens into the cavity of the uterus
Mucosa: inner lining of uterine tube
Has longitudinal folds which project into lumen of uterine tube
Muscular is has: inner circular layer
Outer longitudinal layer
Serosa: the outermost layer of uterine tube
Has endothelium and layer of CT
Mucosal lining is simple columnar epithelium which has ciliated cells and non ciliated cells
Uterus
Receives the developing morula from the uterine tube - embryonic and fetal development occur here
Located between bladder and rectum
Has 2 regions: body - large upper portion, anterior surface is flat, posterior surface is convex
Cervix- lower, barrel shaped part, separated from the body by the ishmus
Uterine wall has 3 layers, outward to in:
Endomettium - mucosa of the uterus
Myometrium - thick muscular layer
Perimetrium - outer serosal layer, has mesothelium, has a layer of loose CT, covers posterior part of uterus and part of anterior surface.
Remaining part of anterior surface consists of CT or adventitia
During reproductive life, endomettium consists of 2 layers: functional layer which proliferates and degenerates during menstrual cycle. The basal layer is retained during menstruation.
Endomettium: lined by simple columnar epithelium and has ciliated and secretory cells.
Surface epithelium invaginates into underlying lamina propria, forming uterine glands - simple tubular glands.
Vagina
A fibromusculae sheath extending from the cervix to the vestibule.
Vaginal wall consists of:
Inner mucosal layer - has transverse folds
Stratified squamous non-keratinised epithelium
It’s surface is lubricated by mucous produced by cervical glands
Intermediate muscular layer:
Has 2 smooth muscle layers - outer longitudinal layer and inner circular layer.
Outer adventitial layer - has an imner ndense CT layer and an outer loose CT layer
External genitalia
Stratified squamous epithelium
Mons pubis:
Rounded prominence over the pubic symphysis
Formed by subcutaneous adipose tissue
Labia mojor:
2 large longitudinal folds of skin
Extend from the !one pubis
Contain a layer of smooth !muscle and subcutaneous adipose tissue
Outer surface is covered with pubic hair
Inner surface is smooth and no hair
Sebaceous and sweat glands are present on both surfaces
Labia minor
Paired, hairless folds of skin that border the vestibule
Has a core of CT within each fold
Contains blood vessels and has sebaceous glands in the stroma
Clitoris:
Erectile structure - has 2 small erectile bodies, the corpora cavenosa
A small rounded tubercle of erectile tissue
Skin over the glans is thin and contains sensory nerve endings
Vestibule:
Lined with stratified squamous!oua epithelium
Has mucous, skene’s and bartholin’s glands
Mammary gland
Modified apocrine sweat gland
When inactive it is composed of 15-20 irregular lobes of branches tubuloalveolar glands - separated by fibrous bands of CT
Has a papilla(nipple)
Areola contains:
Sebaceous glands, sweat glands and modified mammary glands
End in lactiferous duct
Lactiferous sinus:
Dilated portion of the duct
Stratified squamous epithelium at opening
Double layer cuboidal cells at the lactiferous sinus
Single cuboidal or columns cells in secretory portion of the gland
Secretory cells produce:
Merocrine secretion
Apocrine secretion
Colostrum - secretion released after childbirth
Pituitary gland
Pea sized structure found in the sella turcica
Infundibulum - connects the hypothalamus to the pituitary gland
2 lobes Anterior lobe: Derived dro! Ectoderm of oropharynx Glandular epithelial tissue Consists of 3 deriviates- pars tuberalis, pars intermediate, pars distalis
Posterior lobe:
Pars nervosa - has supraoptic and paraventricular nuclei
Infundibulum
Anterior lobe hormones:
ACTH, TSH, FSH, LH, GH, PROLACTIN
Parenchymal cells in anterior pituitary - somatotropes:
Produce GH and regulated by GHRH
Lactotropes: produce PROLACTIN - inhibited by dopamine and stimulated by TRH
Corticotropes: prodcue ACTH - regulated by CTRH
Gonadotropes: produce LH and FSH - regulated by GnRH
Thyrotropes: produce TSH - regulated by TRH
Pineal gland (epiphysis)
Endocrine gland
Regulates daily body rhythm
Attached to the brain by a short stalk
Located on posterior wall of 3rd ventricle
Parenchymal cells of the pineal gland
Pinealocytes: arranged in clumps or chrods within lobules
Interstitial cells: corpora arenacea - calcified concretions
Good marker for radiographic studies
Regulates circadian rhythm
Obtains information about light and dark cycles from the retina via the retinohypothalmic tract
Melatonin: released in the dark
Regulates reproductive function by inhibiting steroidogenic activity of the gonads - influences sexual activity
Neurotransmitters of the pineal gland:
Serotonin, dopamine, norepinephrine
Thyroid gland
Consists of 2 lateral lobes connected by an isthmus - thin band of thyroid tissue
Secretory follicles - its wall has simple cuboidal or low columnar epithelium (follicular cells)
Cells in then follicular epithelium:
Follicular cells - produce T3 and T4
Parafollicular cells - in periphery of follicular epithelium and secrete calcitonin.
It’s function is important to normal growth and development.
Hormones produced: thyroxine T4
Triiodothyronine T3
Calcitonin
Parathyroid glands
Endocrine glands
Located in connective tissue on posterior surface of lateral lobes of thyroid gland
Arranged in 2 pairs: superior parathyroid gland and inferior parathyroid gland
Surrounded by a connective tissue caosule that separates it from the thyroid
Septa - extends from the capsule into the gland to divide it into lobules
Epithelial cells of parathyroid gland:
Principal cells - secrete PTH
Oxyphil cells
