Histology Flashcards
A female 40 years old complained of a swelling at the front of the neck. The swelling moves up and down with swallowing.
a. Name the affected organ.
b. Mention two arteries supplying it.
c. Mention its parts.
d. Mention two nerves related to it.
e. Why it moves with swallowing.
a. Thyroid gland.
b. Superior and inferior thyroid arteries.
a. 2 lobes, isthmus, pyramidal lobe.
c. External laryngeal and recurrent laryngeal nerves.
d. Because it is attached to pretracheal fascia.
A- 65- years-old man was admitted to the hospital complaining of severe difficulty in micturition the condition was diagnosed as benign hypertrophy of the prostate.
a. What is the cause of difficult micturition?
b. Name the lobes of the prostate.
c. Name two arteries supplying the prostate.
d. Name two structures within the prostate.
e. Mention communications of prostatic venous plexus.
a. Enlarged median lobe obstructs the internal urethral orifice.
b. One median and two lateral lobes.
c. Inferior vesical and internal pudendal.
d. Prostatic urethra and 2 ejaculatory ducts.
e. Deep dorsal vein of penis and vertebral venous plexus.
57-years-old woman with a history of chronic anal fissure visited the physician complaining of a painful swelling beside the anal orifice. A diagnosis of ischiorectal abscess was made.
a. What is the cause of the abscess?
b. What are structures that may be damaged by surgical incision of the abscess?
c. Mention the medial boundary of ischiorectal fossa.
d. Mention the lateral boundary of ischiorectal fossa.
e. Why is the anal fissure painful?
a. Spread from infected anal fissure.
b. Inferior rectal nerve and vessels.
c. Levator ani and external anal sphincter.
d. Obturator internus muscle and fascia.
e. Because it is in the lower sensitive part of anal canal which is supplied by somatic nerve.
Mention origin, parts of adenohypophysis & mention types of cells and their percentage of the pars distalis
from pituitary
Thin capsule and reticular stroma
Chromophobes (52%) and chromophils (48%)
Compare between chromophils & chromophobes of the pars distalis
Chromophils: classified into acidophils and basophils
Chromophobes: small cells with pale cytoplasm
Compare between the histological structure of the somatotrophs and mammographs
Somatotrophs: secrete GH, spherical with central rounded nuclei.
Mammotrophs: secrete prolactin, oval cells with oval nuclei
Compare between histological structure of the basophils of the pituitary gands
Thyrotrophs: release TSH, rounded cells with central rounded nuclei
Corticotrophs: release ACTH, MSH, endorphin. has oval cells.
FSH secreting cells: release FSH. Rounded cells with rounded nuclei
LH secreting cells: release LH. Rounded cells with rounded nuclei
Compare between the histological structure of pars tuberalis & intermedia
Pars Tuberalis: basophilic cells arranged in cords
Pars intermedia: formed of cords or follicles of basophilic cells with granular cytoplasm.
Give a short account on neurohypophysis
Contains:
Pituicytes: supporting nerve cells
Nerve fibers: carry neurosecretion to blood capillaries
Herring bodies: contains ADH and oxytocin
Fenestrated blood capillaries
Give a short account on pars nervosa
Contains:
Pituicytes: supporting nerve cells
Nerve fibers: carry neurosecretion to blood capillaries
Herring bodies: contains ADH and oxytocin
Fenestrated blood capillaries
Give a short account on neurosecretory cells of the hypothalamus
They secrete
Oxytocin
ADH
Dopamine
GHRH
GHIH
Give a short account on blood supply of the pituitary gland with reference to portal circulation
Superior hypophyseal arteries supply hypothalamus and stalk
Inferior hypophyseal A supply pars nervosa.
The hormones are transmitted from axon terminals to 1ry capillary plexus & along portal circulation to 2ry plexus.
Compare between the histological structures of zones of suprarenal gland
Zona glomerulosa: columnar, arched groups, rounded, pale, aldosterone
Zona fasciculata: Polyhedral, narrow straight cords, central rounded, pale acidophilic, cortisol
Zona reticularis: polyhedral, branched, central rounded, pale acidophilic, mainly androgens
Give a short account on LM and EM of chromaffin cells of the adrenal
Modified sympathetic neurons which became secretory cells
Central rounded pale nuclei with basophilic cytoplasm.
EM protein forming cells + secretory granules.
Give a short account on the chromaffin reaction:
When a fresh section of suprarenal gland is stained with chromium salt, it turns brown with presence of adrenaline and noradrenalin
Give a short account on para ganglia
Masses of chromaffin cells
They secrete adrenaline and noradrenaline
Compare between follicular and para follicular cells of the thyroid follicles
Follicular: 98%, cuboidal with basophilic cytoplasm and rounded nuclei, has tight junctions with microvilli. Secrete T3 & T4
Parafollicular cells: 2%. Larger cells with paler cytoplasm. secrete calcitonin
Compare between chief cells & oxyphil of parathyroid
Chief cells: smaller but lots, polygonal with rounded nuclei, basophilic, secrete parathormone
Oxyphil cell: Larger but less, rounded cells, acidophilic, unknown function
Mention components of the pineal gland with reference to pinealocytes and its function
Large branched cells with long process and dilation on blood capillaries
Function:
Regulate gonadal function
Regulate sleep rhythm
Describe the histological structure of the ovary
Germinal epithelium: cuboidal epithelium
Tunica albuginea: layer of dense white fibrous CT
Outer cortex: cortical stromal cells
Contents of Graafin follicles
Primary oocyte
Zona pellucida
Corona radiata
Granulosa cells
Theca interna
Theca externa
Give histology of fallopian tube
Mucosa: Simple columnar partially ciliated epithelium
Musculosa: inner circular and outer longitudinal
Serous: loose CT
Fundus and body of uterus
Endometrium: simple columnar partly ciliated epithelium
Contains endometrial glands
Myometrium: thickest part, hormone sensitive, has poorly defined layers
Perimetrium: loose CT
What is the structure of the vagina
Mucosa: non kretanized st. sq epithelium
Musculosa: IC & OL
Adventitia: dense CT and elastic fibers allowing vagina to stretch during labour
Compare between the functional zone and basal zone of the uterus
Functional zone: superficial, upper part of lamina propria, has spiral arteries, sheds and regenerates
Basal part: deep, lower part of lamina propria, straight arteries, unchanged, reserve
Give a short account on uterine cervix
Endocervix: mucus secreting simple columnar cells
Ectocervix: non keratinized st squamous epithelium
Stroma: dense white fibrous CT
Placental barrier
- Layers separating fetal blood from maternal blood.
- Syncytiotrophoblast and cytotrophoblast in the (1st four months of pregnancy, and syncytiotrophoblast only in the last five months).
- Basement membrane of trophoblast.
- C.T. core containing Hofbauer cells
- Basement membrane of fetal blood vessel
- Endothelium of fetal blood vessel
Compare between decidua basalis (maternal part) and chorionic villi (fetal part)
Decidua basalis: part that enters in the formation of the placenta
Fetal part: finger like projections arising from outer wall of blastocyst. They branch and anastomose to embed in decidua basalis. Separated by maternal blood
Compare between cytotrophoblasts and syncytiotrophoblast
Cytotrophoblast: single layer cuboidal cells, no microvilli, disappears at end of 4th month of pregnancy
Syncytiotrophoblast: Cells with no clear boundaries, nuclei are clustered, numerous microvilli, thru all gestation
Give the functions of placenta
1.Allow passage of nutrients from mother to fetus and waste products from fetus to mother.
2.Endocrine function: secreting the following hormones:
- hCG: maintain CL of pregnancy
- HCS:lactogeneic & growth
- Estrogen & progesterone
- Relaxin: sofeting of cervix for labor
3.Placental barrier function:
- Prevents passage of harmful organisms (bacteria) to developing embryo.
- Allows passage of maternal immunoglobulins to the fetal circulation which passively immunizes the fetus against some bacteria.
Compare between resting and lactating mammary glands
Resting: nipple is normal, areola has montgomery glands (lubricate nipple), septa is thick dense CT, lactiferous ducts and small ducts lined with simple cuboidal
Lactating: increase in pigmentation of nipple, increase in secretion of montgomery glands, decrease in thickness of septa, decrease amount of loose CT
Give a short account on stroma of testis
- Tunica vagainalis: double layer of peritoneal pouch
- Tunica albuginea: thick dense white fibrous C.T.
* Thickened posteriorly forming: testis mediastinum
* Seminiferous tubules are embedded in interstitial tissue. - Tunica vasculosa: highly vascular loose C.T. lining tunica albuginea &
septa from inside.
Give a short account on spermatogonia
Initial male germ cell. It is diploid round and small with one or two layers
Compare between primary and secondary spermatocyte
1ry: largest cell. Diploid. chromosomes at coiling process
2ry: Small cells, Haploid. Lasts only for several hours as it divides immediatley
Give a short account on spermatid
Very small cells with central rounded nuclei. they are haploid and near the lumen
Give a short account on spermatozoa
Flattened head and pointed with condensed nucleus
Acrosomal cap
Neck has centrioles
Flagellar axoneme in the end piece
Give the structure and functions of sertoli cells
Tall pyramidal cell occupying thickness of seminiferous tubules
Large oval vesicular nuclei
regulate metabolism of spermatocytes
Give a short account on blood testis barrier and its importance
Definition: Barrier that separates interstitial tissue outside seminiferous tubule from spermatogenic cells inside the luminal compartment of seminiferous tubule.
Functions:
1.Selection of proper nutrients, fluids and hormones needed for spermatogenic development.
- Isolation of the sensitive spermatogenic cells from any damaging substance.
- Creation of a special environment essential for proper spermatogenic development.
- Prevention of autoimmune reaction
Give a short account on LM, EM and functions of Leydig cells
Leydig cells are diffuse types of endocrine cells in close relation of fenestrated capillaries.
They secrete T under control of LH
LM: large polygonal cell
EM: numerous crystalloid inclusion
Give the functions of the epididymis
- Absorption of remaining testicular fluid.
- Propulsion of sperms to vas deferens ⟹ smooth muscles
- Storage of sperms until ejaculation
- Secretion of glycoproteins
- Secretion of glycolipids
- Phagocyosis of residual bodies & degenerated spermatozoa.
Give the histological structure of seminal vesicle
Mucosa: - Highly folded pseudostratified columnar non ciliated epithelium
- Musculosa: includes inner circular and outer longitudinal smooth muscle.
- Adventitia: formed of loose C.T.
Give a short account on prostatic acini
Prostatic acini:
- Arranged in 3 concentric layers: an inner mucosal layer, an intermediate submucosal layer and a peripheral
layer (contain main prostatic acini). - Prostatic acini are lined by simple columnar or pseudostratified columnar epithelium.
