Anatomy Flashcards
Two muscles in the pelvic diaphragm?
Levator ani
Coccygeus
Three muscles that make up levator ani?
Puborectalis
pubococcygeus
iliococcygeus
Two triangles that the perineum can be divided into?
Urogenital triangle
Anal triangle
Brief description of the sympathetic and parasympathetic output to the female genital tract?
Sympathetic comes from Superior hypogastric and joins with the parasympathetic from the inferior hypogastric and then travels to the uterovaginal plexus
In the fetus what cell stage of maturation do eggs undergo, when do they stop?
Beigin Meiosis I but are halted at prophase
Stages of female follicular development?
Primordial
Primary
Secondary (pre-antral)
Tertiary (antral)
Corpus luteum (to corpus albicans 14 days non-pregnant and 3 months if pregnant)
What are the microscopic changes that occur from the development of primary follicle to secondary and then tertiary?
Thecal cells form two layers: theca interna and Externa
(secondary) Fluid filled space forms in granulosa cells - antrum
Single layer of granulosa cells = corona radiata
the stalk = cumulus oorphorus
Before ovulation what stage of the cell cycle does the egg complete and get stopped at?
Completes meiosis I and continues to Meiosis II which is stopped at metaphase
Four sections of the fallopian tube?
Fimbrae, infundibulum, ampulla, isthmus and intramural segment
Three sections of the uterus?
Cervix, body and fundus
Accessory glands of the male genital tract?
Prostate, seminal vesicles and bulbourethral glands
The name of the two tissues that surround the testes?
Tunica vaginalis
Tunica albuginea
What are the seminiferous tubules, rete testes and epididymus of the testes?
Seminiferous tubules - coiled tubules where spermatogenesis occurs
Rete testes - the posterior part of the testes where the seminiferous tubules collect
Epididymus - tightly coiled tube that spermatozoa can travel in, with stereocilia
Types of cells in the seminiferous tubules?
Spermatogenic cells
Sertoli cells - support the spermatogenic cells
Leydig cells
What is the ductus deferens?
Transports spermatozoa from tail of epididymus to urethra
Has tall columnar ciliated epithelium
Thick muscular tube that is also capable of strong contractions during ejaculation
Accessory gland functions in male genital tract?
Seminal vesicles produce 60% of volume, paired
Prostate produces 25%
Bulbourethral gland secretes alkaline and mucus preceding ejaculation to lubricate the urethra
What are the corpus cavernosa and corpus spongiosum of the penis?
2 corpus cavernosa - erectile tissue
1 corpus spongiosum around urethra, contimuous with bulb of penis
Steps of the formation of the primitive sex cords?
- Mesonephros develops gonadal ridges
- Primordial germ cells migrate into gonadal ridges
- Arrival of germ cells induces cells to form the primitive sex cords
How does differentiation to form the testes occur in the developing embryo?
Primitive sex cords develop to form the testicular cords
Fibrous tissue begins to form the tunica albuginea
Leydig cells produce testosterone in week 8 - influences development of ducts and external genitalia
By fourth month testicular cords contain spermatogonia and sertoli cells
How does differentiation to form the ovaries occur in the developing embryo?
Lack of Y chromosome prevents differentiation into testes
Primitive sex cords extend from cortex to medulla
Form clusters and degenerate to form vascula stroma of ovary
Surface epithelium form cortical cords that form ovarian follicles
What is allometric and isometric growth?
Allometric - Change in shape during growth
Isometric - Growth without shape change
Changes to respiratory and cardiovascular system after birth
Closure of ductus venosus, foramen ovale, ductus arteriosus and umbilical arteries
When does the fontanelle close?
Year 2
Phases of growth and development?
Fetus: before birth
Neonate: at time of birth
Infancy: 4 weeks - 2 Years
Childhood: Between infancy and adolescence
Adolescence 10/12 - 20yrs: begins at puberty, ends around 20 years
Adulthood
Different types of ossification?
Endochondral
Intramembranous: dermal/perichondral
What is dermal ossification?
A type of intramembranous ossification
Does not use a cartilage template, uses the flat bones of the skull/mandible
Precess of endochondral ossification?
Begins with a cartilage scaffold (anlage)
Bony collar forms (via perichondral ossification)
Chondrocytes in bony collar die and send out angiogenic signals
There is vascular invasion
Osteoblasts are delivered and they begin to ossify from the centre
What can epiphyseal growth plates sometimes be misinterpreted as on x-rays?
As fractures, can lead to false accusations of abuse
Arterial supply to the breast?
Internal thoracic artery
Lateral thoracic artery
Venous drainage of the breast?
Axillary vein and internal thoracic vein
The lymph nodes that drain the breast?
Axillary lymph nodes
Parasternal lymph nodes
What artery does the anterior-superior pancreato-duodenal artery arise from?
Gastroduodenal
What artery does the inferior pancreato-duodenal artery arise from?
Superior mesenteric
What are the three arteries that supply the adrenal gland?
Superior/middle/inferior suprarenal artery
From what arteries do the Superior/middle/inferior suprarenal arteries arise from?
Superior - from inferior phrenic
Middle - from aorta
Inferior from Renal
Two arteries that supply the thyroid and where they arise from?
Superior thyroid - From the External carotid
Inferior thyroid - From the Subclavian
Where does that subcostal nerve emerge from?
Below the 12th rib
What does the ileohypogastric nerve transverse across?
Transversus abdominis
Order of lumbar nerves from superior to inferior?
Subcostal Ileohypogastric Ileoinguinal Genitofemoral Lateral femoral cutaneous Femoral nerve Obturator nerve Sciatic nerve Pudendal nerve
What are the three layers covering the testis (made from them descending retroperitoneally) made from?
Internal spermatic fascia - transversalis fascia
Cremaster muscle transversalis abdominis and inner oblique
External spermatic fascia - external oblique
The two uterine pouches, their names?
Retrouterine pouch - between uterus and rectum
Uterovesicular pouch - between uterus and bladder
Main divisions of the pudendal nerve?
Dorsal nerve to penis
Deep perineal (over pelvic floor)
Superficial perineal (becomes posterior scrotal -male or labial -Femal
Inferior rectal nerve
Two main cells of the pituitary gland, how they stain and the hormones they produce?
Basophil - darkly stained - ACTH, TSH and LH/FSH
Acidophil - lightly stained - GH, Prolactin
Arterial supply to the pituitary gland?
Superior and inferior hypophyseal arteries
Where does the blood and the hormones of the pituitary gland drain to?
The cavernous sinus (through hypophyseal vein)
Two cells in the thyroid gland, and what they secrete?
Follicular cells - produce thyroglobulin which is converted to T3 and T4 before release
Parafollicular cells - secrete calcitonin
Cells in the parathyroid glands and what they do?
Chief cells - PTH synthesis
Oxyphil cell - no secretion (large cytoplasm)
Adipocyte - Fat storage (very large and white)
Lymph drainage from the thyroid gland?
Deep and superficial cervical nodes
Fascia that encloses the thyroid gland?
Pretracheal fascia (on outside)
Inner fascia (on inside)
Blood supply to the parathyroid glands?
Inferior thyroid arteries
Cancer/enlargement of the thyroid gland can compress what structures?
Trachea/oesophagus/veins
Difficulty breathing and swallowing
Three types of cells in the pancreas and their secretions?
Alpha cells - Glucagon
Beta cells - Insulin
Delta cells - Somatostatin
Cells in the medulla of the adrenal gland?
Chromaffin cells
How do hormones from the cortex of the adrenal gland get secreted into the bloodstream?
Through thin walled vessels called sinusoids that travel to the medulla
Venous drainage of the adrenal glands?
Single suprarenal vein, on right drains into renal vein and on the right the inferior vena cava
Two muscles of the lumbar spine region that support it?
Erector spinae muscle and transversospinales muscle
What ligaments stabilise the sacroiliac joints?
Anterior and posterior interosseous ligaments
The three different types of pelvis shapes, and who they usually belong to?
Android - either male of female (heart shaped)
Anthropoid - usually male (thinner and longer)
Gynecoid - Usually female (wider and shorter)
The acetabulum in males and females differs how?
Male - deeper
What is the linea alba?
Muscles of the anterior abdominal wall that have joined in a midline raphe
The layers of the thoracolumbar fascia?
Posterior layer - thick and strong covering posterior surface of erector spinae
Middle layer - Lies between erector spinae and quadratus lumborum
Anterior layer - thin, covers anterior surface of quadratus lumborum
What is the rectus sheath?
The fascia covering the rectus abdomis that is adherent to the intersections between the rectus abdominis
Actions of psoas major?
Flexion of hip joint
Actions of quadratus lumborum?
Bend the trunk ipsilaterally
Actions of transversus abdominis?
Flex and rotate the trunk
Actions of iliacus?
Flexion and external rotation of the hip joint
What forms the floor of the inguinal canal?
The inguinal ligament
What is the deep inguinal ring and the superficial inguinal ring?
The deep inguinal ring: The opening in the transversalis fascia that the fascia extends through to the inguinal canal
The superficial inguinal ring is the ring that the inguinal canal ends at the medial end of the inguinal ligament
What does the inguinal canal contain in the male and in the female?
Female: round ligament of uterus, genital branch of genitofemoral nerve
Male: Vas deferens, testicular artery/veins, nerves and lympatics. And genital branch of genitofemoral nerve
Spinal nerve root value for iliohypogastric nerve? Distribution?
L1 - abdominal muscles and skin of inguinal/pubic ares
Spinal nerve root value for ilioinguinal nerve? Distribution?
L1 - skin of penis and scrotum in males, skin covering mons pubis and labia majora in females
Genitofemoral nerve root value for genitofemoral nerve? Distribution?
L1-L2 :
Femoral branch: skin over femoral triangle
Genital branch: cremaster muscle, scrotum in males, mons pubis and labia majora in females
Lateral femoral cutaneous nerve spinal root value and distribution?
L2-L3: cutaneous innervation to lateral thigh
Femoral nerve spinal root value and distribution?
L2-L4: Hip/knee flexors
Obturator nerve spinal root value and distribution?
L2-4: adductors of the thigh
What is the tunica vaginalis, in the male?
The layer of fascia that is directly around the testes
Where do the left and right testicular arteries arise from?
The left from the abdominal aorta
The right from the right renal artery
What is the pampiniform plexus?
The venous plexus that forms around each testicle, in the scrotum
Where do sympathetic fibres that supply the testicle arise from?
T10
Lymph nodes that drain the testicles?
Para-aortic nodes (epigastric)
Two parts of the prostate gland?
Glandular part, fibromuscular part
Also two lobes connected by an isthmus
Arterial supply of the prostate?
Prostatic arteries, branches from inferior vesicle, middle rectal and pudendal (all off internal iliac)
What are the mesosalpinx and mesovarium?
Mesosalpinx - Portion of the mesentery (broad ligament) covering the fallopian tube
Moesovarium - portion of the mesentery (broad ligament) coving the ovaries
Blood supply to the ovaries?
The ovarian arteries, branch from the abdominal aorta
What is the suspensory ligament of the ovary?
The mesentery of the broad ligament that attaches the ovaries to the ligament
Venous drainage to the uterus?
Uterine plexuses draining to the internal iliac veins
Left to left renal vein
Right to inferior vena cava
Cervical canal epithelium?
Simple columnar mucus secreting
The ectocervix’s (part that projects into vagina) epithelium?
Non-keratinized stratified squamous
Arterial/lymph and venous supply to the vagina?
Arterial from internal iliac arteries
Venous is from venous plexuses to internal iliac
Iliac lymph nodes above the hymen and superficial inguinal below
How is the peritoneal space in males and females different?
Clinical implications?
On males it is closed
In females it communicates with the uterine tube and is open
Means genital tract infections can spread to the peritoneum in the female
Lymph drainage of the uterus?
Fundus - pre-aortic nodes
Body and cervix - iliac nodes
Nerve supply to the uterus and vagina?
Sympathetics from T10-L2 form the uterovaginal plexus
Parasympathetics S2-4 are pelvic splanchnics
Inferior aspect of the vagina is the pudendal nerve
Visceral afferents for body and fundus of uterus travel with T10 and 11, visceral afferents to cervix and vagina travel with pelvic splanchnics to S2-4
Parietal branches of the internal iliac artery in male and female?
Iliolumbar Lateral sacral Superior gluteal Inferior gluteal Internal pudendal Obturator
Visceral branches of the internal iliac (female)?
Uterine artery
Vaginal artery
Superior vesicle (to bladder)
Middle rectal
Visceral branches of the internal iliac (male)?
Superior vesicle
Inferior vesicle
Middle rectal
Lymph from the testis and epididymus/scrotum/seminal vesicles and prostate and vas deferens drain to which nodes?
Testis and epididymus to para-aortic
Scrotum to superficial inguinal
Seminal vesicles/prostate/vas deferens to internal iliac
The muscles which form a sling around prostate or vagina are what muscles?
Levator prostate or sphincter vagina
What ligaments hold the cervix in place?
Transverse cervical ligaments (superior end of vagina to lateral pelvic wall.
Pubocervical ligaments and sacrocervical ligaments connect the cervix to the pubis and sacrum respectively
What muscle stretches below the perineal membrane over the urethra?
Sphincter urethrae
What are the spaces below the urogenital triangle of the perineum called, what separates them?
Superficial and deep perineal pouches
Separated by the perineal membrane - the superficial is superficial to the membrane
What is the perineal body?
Small wedge shaped mass of fibrous tissue in the midline between the deep and superficial perineal pouches
The crus of the penis on both sides become what in the male?
Corpora cavernosa of the penis
the Corpus spongiosum becomes what on the deeper part of the penis?
The bulb of the penis
What two muscles cover the corpus spongiosum and cavernosa on males?
Corpus spongiosum is covered by bulbospongiosus
Corpus cavernosa is covered by the ischiocavernosa muscles
What is the labia majora and minora?
The surrounding tissue to the vaginal vestibule, the minora the inner and the majora the outer
What is the erectile tissue on either side of the vestibule, in the superficial perineal pouch called? What muscle lies superficial to it?
The bulb of the vestibule, Bulbospongiosus
What tissue lies below the ischiocavernosa in the female, that connects to the clitoris?
Ischiocavernosa
What fossae are deep to the skin of the ischioanal fossae?
Wedge shaped compartments either side of the anal canal
Filled with fat and connective tissue
What nerve supplies the perineum? What are the spinal root values of this nerve?
Pudendal nerve S2,3 and 4
Two branches of the pudendal nerve?
Penile/clitoral nerve
Perineal nerve
Arterial supply to the perineum?
Internal pudendal artery
Lymphatic drainage of the perineum?
To the superficial inguinal nodes
What is the sharp bend in the rectum at the anorectal junction called, what causes this bend?
Perineal flexure - maintained by the puborectalis muscle
What is the rectovesical pouch
The puch formed in males by the peritoneum between the rectum and bladder
Arteries to the penis?
Deep and dorsal arteries from the internal pudendal artery
Deep - erectile
Dorsal - superficial
Basic process of fertilisation, cleavage and implantation in the developing embryo?
After fertilisation the oocyte becomes the zygote.
The zygote divides (cleavage) to form many cells, the morula
The Morula at day 5 is reorganised to form an inner cell mass and an outer cell mass, the whole structure is now called the blastocyst
The inner cell mass differentiates into a hypoblast (thin layer that doesn’t develop) and an epiblast.
The space made up by the epiblast is called the amnion or amniotic cavity and the larger space made up by the hypoblast and outer cell mass is the yolk sac
The epiblast then differentiates in gastrulation to become the Endoderm, mesoderm and ectoderm.
Difference in primary and secondary ossification?
Primary is the formation of new bone at the start of life and secondary is the enlargement of bone at later stages of life
What are the primary ossification centre and secondary ossification centre called, what are they? what is the epiphyseal growth plate?
The primary ossification centre (diaphysis) is the centre of bone where primary ossification has occurred, and epiphysis is the edges of bone where bones elongate in secondary ossification
The epiphyseal growth plate is the specialised cartilage that separates the two
Secondary male sex characteristics?
Pubic hair, axillary and facial hair 2 years later
broadening of the shoulders and growth of the larynx
Secondary female sex characteristics?
Pubic hair at puberty, axillary hair a few years later
Broadening of the hips and fat redistribution to the hips and buttocks
Main blood supply to the breast?
Mainly by the internal thoracic artery but also by lateral thoracic
What thracic spinal segments supply the breast? Through what nerves?
T4 - 6 through anterior and lateral branches of intercostal nerves
Lymph nodes of the breast?
Parasternal
Axillary
Changes to the breast in pregnancy?
Proliferation of the glandular cells of the breast
What is the decidua?
What are the three layers?
Portion of the endometrium which lines the uterus that has become modified
Decidua basalis
Decidua capsularis
Decidua parietalis
What does the chorionic villi grow into to form the placenta?
The decidua basalis
How does oxygenated and nutrient rich blood from the mother get into the fetus?
Leaves the placental via the umbilical vein to reach the fetus at the umbilicus
How do waste products and deoxygenated blood return from the fetus to the mother?
Two umbilical arteries (branches of internal iliac - in fetus)
