MALE UROGENITAL SYSTEM GROSS ANATOMY

Question 1

reproductive system definition

Answer 1

the biological system made up of all the anatomical organs involved in sexual reproduction

Question 2

two external genital organs

Answer 2

penis and scrotum

Question 3

explain gross structure of penis

Answer 3

penis- formed of root, containing the bulb of penis and crura, formed of corpora cavernosa

body- shaft

neck

glans penis- bulbous shaped top, supported and protected by the foreskin formed of corpus spongiosum

Question 4

explain more complex penis structure

Answer 4

consists of three cylindrical masses of erectile tissue, two corpora cavernosa lying adjacent to each other

corpus spongiosum lying ventrally and surrounding the uretrha

Question 5

where does the bulb of the penis lie?

Answer 5

superficial perineal pouch

Question 6

what is the ventral side of the penis marked by?

Answer 6

a groove in the lateral direction

Question 7

where is the foreskin attached?

Answer 7

underside of the penis by the frenulum

Question 8

three different parts of the urethra explained

Answer 8

prostatic- when passing through the prostate

membranous- passes through the perineal membrane, forming the narrowest part of the male urethra

penile- when in the penis

Question 9

scrotum definition

Answer 9

structure located caudal to the penis, consisting of a suspended dual chambered sack of skin and smooth muscle

it is a distention of the perineum

Question 10

what does the scrotum contain

Answer 10

external spermatic fascia, testes, epididymus and ductus deferens

Question 11

two important muscles in the scrotum

Answer 11

cremaster muscles and dartos muscles

Question 12

location of cremaster muscles

Answer 12

muscle that covers the testis and spermatic cord

between the external and internal spermatic fascia

Question 13

structure of cremaster muscle

Answer 13

paired structure

thin layer of skeletal striated muscle

Question 14

function of cremaster muscle explained

Answer 14

raise and lower testes in order to regulate scrotal temperature for optimal spermatogenesis and survival of resultant spermatozoa

involuntary muscle, contraction can occur during arousal which can prevent injury to the testicles during sex

contract during ejaculation

Question 15

important reflex explained

Answer 15

cremaster reflex

stroke skin from inner thigh towards knee

stimulates sensory fibres of ilioinguinal nerve

stimulates motor fibres of the genital branch of the geniofemoral nerve

provides innervation to cremastor muscles causing the contraction of the muscle and elevation of testes

Question 16

how else can the cremaster be stimulated to contract?

Answer 16

performing Kegels or by flexing and tightening abdominal muscles

Question 17

movement of pulling testes superiorly

Answer 17

retraction

Question 18

dartos structure + location

Answer 18

dartos fascia is an external layer of connective tissue with muscle found in the penile shaft, foreskina nd scrotum

Question 19

dartos function

Answer 19

carries blood supply of the penile skin

acts to regulated temperature of testis by expanding or contracting to wrinkle the scrotal skin

contraction reduces the SA available for heat loss- worming testicles

dartos muscle works in conjuction with cremaster

Question 20

testis definition

Answer 20

primary sex organs of the male and produce spermatozoa and hormones

Question 21

structures within testis

Answer 21

seminiferous tubules, epidyimus, rete testis, vasa efferentia, vas deferens

Question 22

seminiferous tubule structures

Answer 22

several coiled tubules within the central testes, sites of spermatozoa production

Question 23

explain drainage from seminiferous tubules

Answer 23

drain from the testes into the rete testis

then via a series of vasa efferentia tubules into a coiled single duct of the epididymus

epididymus then becomes the uncoiled ductus deferens at the posterior pole of the testis

ductus deferens enters the spermatic cord, passing through the inguinal canal, reching the urethra

Question 24

what is the spermatic cord?

Answer 24

cord like structure formed by the vas deferens and surrounding tissue that runs from the deep inguinal ring down to each testicle

Question 25

what are the seminal vesicles?

Answer 25

sacs lying lateral to the ducti deferentes, lie behind the urinary bladder

secrete fluid that partly composes the semen

Question 26

seminal vesicle and vas deferens association

Answer 26

vas deferens and seminal vesicle excretory duct join to form the ejaculatory duct

Question 27

where does the ejaculatory duct go?

Answer 27

passes through the prostate and then opens into the prostatic urethra

Question 28

prostate definition + structure

Answer 28

exocrine gland found below the bladder, with the urethra passing though it

Question 29

prostate function

Answer 29

secretes a fluid that contributes to the volume of the semen

alkaline and milky, forming 30% of the semen

contain the ejaculatory ducts, which the vas deferens and seminal vesicles empty into, to then join the prostatic uretrha

Question 30

secretions in prostate seminal fluid

Answer 30

proteolytic enzymes, postatic acid phosphatase, zin

Question 31

seminal vesicle secretions + percentage

Answer 31

alkaline fluid with fructose, which acts as a energy source for sperm

forms 70% of seminal fluid

Question 32

main blood supply to the pelvis and its viscera

Answer 32

from internal iliac artery

Question 33

where does the internal iliac artery form?

Answer 33

abdominal aorta bifurcates into left and right common iliac artery

the common iliac artery then bifurcates into the internal and external iliac artery at the sacroiliac joint

Question 34

what does the internal iliac artery divide into?

Answer 34

anterior and posterior trunks

Question 35

what does the anterior trunk divide into + what structures they supply?

Answer 35

anterior- pelvic viscera, perineum, gluteal region and adductor compartment of the thigh

umbilical artery- superior vesical artery- bladder

inferior vesical artery- bladder, seminal vesical, prostate

internal pudendal- greater sciatic foramen, travelling with pudendal nerve to enter the lesser sciatic foramen- to perineum- erectile tissue of penis

Question 36

where does the testicular artery originate from?

Answer 36

a branch of the abdominal aorta that originates before the inferior mesenteric

paired arteries

Question 37

explain venous drainage of testes

Answer 37

testicular vein, male gonadal vein, carries deoxygenated blood to the inferior vena cava

paired vein

right testicular vein joins inferior vena cava

left one joins left renal vein