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Bio 125 Anatomy final

96 important questions on Bio 125 Anatomy final

What is hydrochloric acid?

a strong acid that destorys many harmful bacteria in the food

Where does the stomach lie?

in the upper left quadrant of the peritoneal cavity

Greater curvature of stomach

entire extent of the convex lateral surface

Lesser curvature of the stomach

concave medial surface

What are the 3 subdivisions of the small intestine?

duodenum(5%) jejunum (40%) and ileum (55%)

Which two ducts enter the wall of the duodenum

pancreatic and common bile ducts
they form a bulb called the hepatopancreatic ampulla.

What does the hepatopancreatic ampulla do?

opens into the duodenum via a mound called the major duodenal papilla

What are the 3 structural modifications that amplify the absorptive surfaces of the wall of the small intestines ?

1.circular folds (plicae circulare)
2.villi
3.microvilli

Circular folds (plicae circulares)

1 cm tall transverse ridges of the mucosa and submucosa
-force the chyme to spiral through the intestinal lumen ...slowing its movement

What are absorptive cells?

uptake digested nutrients...contain many mitochondria
contain and abundant amount of endoplasmic reticulum.

Epithelial stem cells divide in the crypt and they....

renew the mucosal epithelium by moving continously into the villi

Large intestines main functions?

absorb water. and electrolytes(12-24hours)
digested residue contains few nutrients
small amount of digestion by bacteria
mass peristaltic movements force feces toward the rectum

What is the large intestine subdivided into

cecum, appendix, colon, rectum, anal canal

The large intestine exhibits what 3 special features?

Teniae coli
Haustra
Epiploic appendages

What is the largest gland in the body

the liver (3lbs) performs over 500 functions

What are some of the major functions of the liver

metabolism, glycogen storage, decomposition of red blood cells, plasma protein synthesis, and detoxification

The livers digestive function is to

produce bile; and alkaline compound which aids in digestion, via the emulsification of lipids.

Most of the liver is covered with a layer of visceral peritoneum except

the superior part (bare area) is fused to the diaphragm and is a devoid of peritoneum

What are the 4 lobes of the liver

left, right, caudate, quadrate lobes.

The right and left branches of the hepatic portal vein carry?

carry nutrient rich blood from the stomach and intestines

Exit-the right and left hepatic ducts carry

bile from the respective lobes exit and fuse to form the common hepatic duct

Bile which is synthesized in the liver is carried where

to the right and left hepatic ducts, which converge to form the common hepatic duct. there it enters the superior end of the common bile duct and either empties into the second part of the duodenum or enters the cystic duct to be stored in the gallbladder .

What is the pancreas exocrine function

Acinar cells; make, store, and secrete pancreatic enzymes which are activated in the duodenum and breaks down food.

The kidneys lie where and how?

"retroperitoneal" (behind the parietal peritoneum) in the superior lumbar region of the posterior abdominal wall
they extend from the level of the 11th/12th thoracic vertebrae to the 3rd lumbar vertebrae

Where is the right and left kidney positioned

R: crowded by the liver and lies slightly inferior to the left

The perirenal and pararenal fat layers function to..

cushion the kidney against blows and help hold the kidney in place

The broad base of the pyramid abuts the ____ while the apex (papilla) points internally

cortex

What seperates the adjacent pyramids

inward exstensions of the renal cortex

How many lobes does a kidney have

5-11 (single renal pyramid plus cortical tissue surrounding it)

What is the order that the kidney works in

renal papillae-minor calyx- majorcalyx- renal pelvis- ureter- bladder- urethra- outside of body

What does a urine-forming nephron consist of

renal corpuscle. proximal convoluted tubule, a looof henle and a distal convoluted tubule

A collecting duct is involved in?

concentrating urine by removing water from it

What kind of epithelium lines the uriniferous tubule

simple epithelium

A nephron is the ___ and main function is to...

basic structural and functional unit of the kidney
- Its chief function is to regulate the concentration of water and soluble substances like sodium salts by filtering the blood, reabsorbing what is needed and excreting the rest as urine.

The purpose of the renal corpuscle is to

extract the renal filtrate (it is not yet to be called urine) from the blood

The glomerular endothelium is ____ which allows large quantities of fluid and small molecules to pass from the capillary into the hollow interior of the glomerular capsule....the capsular space.

fenestrated

Bowman's capsule (glomerular capsule)

and expanded end of the renal tubule
it contains the glomerulus (capillary network)
-the inner layer is very porous to extract and absorb plasma from the glomerulus
-the outer layer is impermeable to contain the plasma that has been extracted.

Distal convoluted tubule

cuboidal cells without microvilli that function more in secretion than in reabsorption
-confined to the renal cortex

The collecting duct system

recieves urine from several nephrons and runs straight through the cortex into the deep medulla
-concentrates urine..ADH hormone increases permeability of the collecting tubules and ditstal tubules to water
- at the apex of the pyrimid, adjacent collecting tubules join to form larger papillary ducts, which empty into the minor calices

What are the two categories nephrons are divided into according to location?

cortical nephrons and juxtamedullary nephrons

Ureters L and R are...

muscular ducts (10 inches) that propel urine from kidneys to the urinary bladder
-each begins at the level of L2 as a continuation of the renal pelvis
-descends retroperitoneally though the abdomen and enter the bladder through the posterior wall.
-the distal end close in response to any increase of pressure with in the bladder to prevent back flow of urine

Ureters actively propel urine into bladder via

response to smooth muscle stretch

Bladder- muscular layer

thick detrusor muscle; consist of smooth muscle fibers arranged in inner and outer longitudinal layers and a middle circular layer...contraction squeezes urine from bladder during urination.

As urine accumulates the bladder expands without significant rise in ___?

internal presure

What keeps the urethra closed when urine is not being passed ?

sphincters

Internal urethral sphincter

involuntary sphincter at the bladder-urethra junction

Levator ani muscle

voluntary urethral sphincter

In males the urethra is about 8 inches and has 3 named regions name them

prostatic urethra, membranous urethra, spongy urethra

Spongy urethra (penile)

15 cm long, passes through the entire penis, and opens at the tip of the penis via the external uretheral orifice

Micturition (voiding urination)

the act of emptying the bladder
-caused by the contradiction of the bladders detrousor muscle, assisted by the muscles of the abdominal wall.
-controlled by the brain..distension of the bladder wall stimulates stretch receptors that initiate spinal reflexes at the sacral region that stimulate contraction of external urethral sphincter and inhibit the destrusor muscle and internal sphincter (temporarily)

Primary organs (gonads)

the testes in the males and the ovaries in female.
-produce the sex cells (gametes)...sperm (males) and egg/ovum (females)
-the gonads also function as endocrine glands and secrete sex hormones.

Accessory sex organs

all other genitalia... including the internal glands and ducts and the external genitalia.

Where does the sperm-producing testes lie?

in the scrotum

Accessory sex glands empty their secretions into..?

the sex ducts during ejaculation (seminal vesicles, prostate gland, and bulburethral gland)

The scrotum also responds to changes in external temperature how?

under cold conditions, the testes are pulled up toward the warm body wall, and the scrotal skin increases its thickness to reduce heat loss

Each testes is posterior to, and partially encloded by a serous sac called the

tunica vaginalis

Deep to the visceral layer of the tunica vaginalis lies the tunica albuginea

the fibrous capsule of the testis
-septal exstensions of the tunica albuginea project inward to divide the testis into 250 to 300 wedge-shaped compartments called lobules...each containing 1-4 coild seminiferous tubules (sperm factories)

The seminiferous tubules of each lobule converge posteriorly to form a ?

tubulus rectus: a straight tube that conveys sperm into the rete testis
-from the rete testies, sperm leave the testies through about a dozen efferent ductules that enter the epydidimus

Where do testes recieve their arterial blood from

the long testicular arteries, which branch from the aorta in the superior abdomen

Seminiferous tubules are seperated from each other by

an areolar CT

Seminiferous tubules epithelium ?

-the sperm-forming tubules consist of a thick stratified epithelium surrounding a hollow central lumen
- the epithelium consist of spherical spermatogenic (sperm-forming) calls embedded in columnar sustentacular (supporting) cells

Spermatogonia (germ cells)

-the least differentiated cells located peripherally on the epithelial basil lamina
-as the spermatogonia differentiate and move inward toward the lumen they produce:primary~secondary~spermatocytes~spermatids~spermatozoa

What happens in the stage 1 of formation of spermatocyes?

spermatogonia divide vigorously and continuously by mitosis... producing two distinctive daughter cells.

What are the 2 types of daughter cells formation of spermatocytes forms

type A daughter cells
type B daughter cells

Type a daughter cells:

remain at the basal lamina to maintain the germline

Sustentacular cells (sertoli cells)

surround the spermatogenic cells and extend from the basal lamina to the lumen.
-the sustentacular cells are bound to each other by tight junctions on their lateral membranes and divide the seminiferous tubulees into two compartments

What are the two compartments that seminiferous tubules divide into?

basal compartment
adluminal compartment

What are some of the ways sustentacular cells assist sperm production?

-supplies nutrients to the spermatogenic cells
-actively moves the spermatogenic cells toward the lumen
-phagocytizes the cytoplasm that is shed as spermatids become sperm
-secretes testicular fluid into the tubule lumen, which pushes sperm through the tubule and out of the testes
-secretes androgen-binding protein, which concentrates testosterone near the spermatogenic cells (testosterone stimulate spermatogenesis)
-Secretes the hormone inhibin, which slows the rate of sperm production

Seminiferous tubules are surrounded by several layers of smooth muscle-like myoid cells that contract rhythimically to...

help squeeeze sperm and testicular fluid through the tubules and out of the testies

The loose CT between the seminiferous tubules contain clusters of ?

interstitial cells (leydig cells) that make and secrete the male sex hormones (androgens)

The duct of the epididymis has what type of epithelium

dominated by a tall, pseudostratified epithelium that contains tuft of long microvilli called stereocilia that provides a vast surface area for -reabsorbing testicular fluid and -transferring nutrients and secretions to many sperm that are stores in the lumen of the epididymus
- surrounded by a layer of smooth muscle

What does the ductus deferens do (vas deferend)

store and transpots sperm during ejaculation
-runs superiorly from the scrotum. its distal end expands as the ampulla of the ductus deferens and then joins with the duct of the seminal vesicle to form the short ejaculatory duct. each ejaculatory duct runs within the prostate gland, where it empties into the prostatic

What does the wall of the ductus deferens consist of?

1) an inner mucosa which consist of a psuedostratified epithelium underlain by a lamina propria.
2) and extremely thick muscularis
3) an outer adventitia
-during ejaculation the smooth muscle in the muscularis creates strong peristalic waves that rapidly propel sperm through the ductus deferens to the urethra.

The ductus deferens is the largest component of the __?

spermatic cord: a tube of fascia that also contains the testicular vessel and nerves.
-the inferior part of the spermatic cord lies in the scrotum, and its superior part runs through the inguinal canal

The urethra consist of what 3 parts?

1) prostatic urethra (prostate)
2) membranous urethra (urogenital diaphragm)
3) spongy urethra (penis)

The coiled seminal vesicles lie ___to the bladder

posterior
-the size of a finger

In seminal vesicles the mucosa is doled into a honey comb pattern of crypts and blind chambers and the epithelium is composed of ?

a lining epithelium psuedostratified columnnar
-the external will is composed of a fibrous capsule of dense connective tissue surrounding a thick layer of smooth muscle ..contracts during ejaculation to empty the gland.

The secretion produced by the seminal vesicles constitutes ___ of the volume of semen?

60-70%

The secretion of the seminal vesicles contains the following:

-fructose and other nutrients
-prostaglandins..stimulates contraction of the uterus to help move sperm through the female reproductive tract
-substances that suppress the immune response against semen in females
- substances that enhance sperm motility
-enzymes that clot the ejaculated sperm in the vagina and then liquefy it so that the sperm can swim out.
~a yellow pigment produced by the seminal vesicle fluoresces under ultraviolet light

The duct of each seminal vesicle joins the ductus deferens on the same side of the body to form an...?

ejaculatory duct within the prostate gland.
-sperm and seminal fluid mix in the ejaculatory duct and enter the prostatic urethra together during ejaculation

The prostate lies inferior to the bladder and consist of ?

20-30 compound glands of 3 classes A) main B) submucosal C) musical glands...embedded in a mass of dense CT and smooth muscle called fibromuscular stroma and surrounded by a CT capsule

The muscle of the stroma contracts during ejaculation to squeeze the ?

prostatic secretion into the urethra

Prostatic secretion makes up ___% of the semen volume

33-40

Prostate-specific antigen (PSA):

enzyme that liquefies semen
-measuring the levels of PSA in a man's blood is the most important method of screening for prostate cancer (elevated levels of PSA are characteristic of prostate cancer.

The skin covering the penis is loose and extends distally around the glands to form a cuff, called the __?

prepuce or foreskin

As erectile bodies begin to swell they..

press on the small veins that normally drain them, slowing venous drainage and maintaining engorgement.

The arrangement of the collagen fibers in the dense CT outside the erectile bodies does what to the penis during erection?

strengthens the penis
-longitudinal fibers lie at right angles to circular fibers that forms rings around the penile shaft.

The main substance of the ovary is divided into and outer cortex and inner medualla name them?

-ovarian cortex
-ovarian medulla

Follicular cells multiply (follicle 3)

a stratified epithelium forms around the oocyte; from this point on follicular cells are called granulosa cells

Zona pellucida forms (follicle 4)

the oocyte developes a glycoprotein coat (zona pellucida)..a protective shell
-theca folliculi: a layer of CT condenses around the exterior of the primary follicle

Antrum forms (follicle 5)

a clear liquid gathers between the granulosa cells and coalesces to form a fluid-filled cavity (antrum); the follicle is now a secondary follicle; antrum expands with fluid and a coat of granulosa cells (corona radiata) surrounds the oocyte

3) luteal phase (follicle 8-9)

after ovulation, the part of the follicle that stays in the ovary collapses and its wall is thrown into wavy folds (follicle 8) ...this structure is called the corpus luteum

Luteal phase (follicle 8-9) if there is no implantation, then

the corpus luteum dies after 2 weeks and becomes a scar called a corpus albicans
-stays in the ovary for several months, shrinking until it is phagocytized by macrophages

Uterine tubes/fallopian tubes/oviducts:

receives ovulated oocyte and provides a site for fertilization.

The uterine tubes have little or no direct contact with the ovaries, therefore ovulated oocyte are cast into the__?

peritoneal cavity
-beating cilia on the fimbriae create currents to carry the oocyte into the unterine tube
- the oocyte is carried toward the uterus by peristalsis and ciliary action
-nonciliated cells keep the oocyte and the sperm nourished and moist

Externally the uterine tube is covered by _ and supported by?

peritoneum and supported by a short mesentery called mesosalpinx:a part of the broad ligament

The question on the page originate from the summary of the following study material:

Bio 125 anatomy

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