Module 11 Flashcards
how are the accessory digestive organs beneficial?
- significant part of acquiring nutrients from food
- provide enzymes for the breakdown of food molecules and bile for the digestion of dietary fat
- an important process in the storage of molecules that provide energy for the body
what are the three accessory digestive organs?
- liver
- gall bladder
- pancreas
what is the function of the liver?
- produces bile for the digestion of fats
- stores dietary glucose in the form of glycogen, so that is can be later broken down and converted to energy
the liver stores dietary glucose in the form of ______
glycogen
the liver plays a role in the metabolism of _____, ____ and _____ in the blood
toxins, drugs and alcohol
the pancreas is a _____ gland
mixed
what is the endocrine function of the pancreas?
controls levels of blood glucose
what is the exocrine function of the pancreas?
secrete digestive enzymes into the intestine
where is the liver located?
upper right abdominal quandrant, inferior to the diaphragm and anterior to the inferior vena cava
what are the four lobes of the liver
- right
- left
- caudate (below)
- quadrate (above)
what is the purpose of the ligaments of the liver?
attach the liver to the surrounding abdominal peritoneum and the diaphragm
which ligament separates the right and left lobes of the liver?
falciform ligament
the porta hepatis is also known as the
hilum or hepatic portal
what happens at the hilum of the liver?
where the hepatic vessels and ducts enter and leave the liver
where is the porta hepatis of the liver located?
on the inferior of the liver surrounded by the four lobes
what are the three components of the porta hepatis?
- portal vein
- hepatic artery
- common hepatic duct
what does the portal vein do?
carries nutrient rich blood from the digestive system into the liver, where those nutrients absorbed from the digested food can be stored
any toxins or drugs that are ingested travel through the _____ into the liver to be metabolized
portal vein
what does the hepatic artery do?
carries oxygenated blood to the liver
the hepatic artery _____ to supply each ___ of the liver
branches, lobe
what does the common hepatic duct do?
drains the bile produced in the liver
the common hepatic duct joins with the _________ to form the common bile duct
cystic duct of the gall bladder
what are the functional units of the liver called?
liver lobule
what shape are the liver lobule
hexagonal
what kind of cells make up the liver lobule?
cuboidal liver cells called HEPATOCYTES
how are hepatocytes arranged?
in plates (cords) that radiate outward from a central vein
between the plates of the hepatocytes are spaces called _____ where…
sinusoids where venous blood flows through
what are portal triads?
branches of the hepatic artery, portal vein, and common duct from the porta hepatis
each lobule is surrounded by ___ triads
six (one for each corner of the hexagon)
how does venous blood flow through the liver lobule?
- nutrient rich blood from the portal veins travels in the sinusoids
- in sinusoids, nutrients from the blood are taken up into the hepatocytes
- the blood in the sinusoids then drains into the central veins, which join to form the hepatic veins
bile is produced by what cells
hepatocytes
purpose of bile
aid in digestion of dietary fats
where does bile flow after it is produced in the hepatocytes?
drains into small channels called canaliculi, that empty into the bile ductules of the portal triad, and eventually the hepatic ducts
what is liver cirrhosis?
- slow progressive disease
- healthy liver tissue is replaced by scare tissue (prevent liver from functioning properly)
symtpoms of liver cirrhosis?
block the flow of blood and bile through the portal triads of the liver.
- jaundice (yellowing of skin) due to build up of bile
- distended abdomen due to buildup of fluid from the venous system
what shape is the gall bladder
pear
where is the gall bladder located?
inferior to the right lobe of the liver
what is the function of the gallbladder?
store and concentrate bile not immediately required for digestion
the three anatomical features of the gall bladder
- fundus (anterior)
- body
- neck (posterior, connected to cystic duct)
what does the biliary system consist of?
interconnected ducts that connect the liver and the gallbladder
what does the biliary system do?
stores and drains bile into the duodenum
what are the three components of the biliary sysem
- hepatic ducts
- cystic duct
- common bile duct
how many hepatic ducts are there? why/
2 - right and left, one from each side of the liver
where does the bile go after the hepatic ducts
into the common hepatic duct
function of the cystic duct?
transport bile to and from the gall bladder
the common bile duct enters the ______
duodenum
pancreas shape and location
lobular organ that lies deep to the stomach
what are the three divisions of the pancreas?
- head
- body
- tail
where is the head of the pancreas located?
sits in the concavity of the duodenum on the right side of the abdominal cavity
where is the body of the pancreas located?
extends towards the left, passing behind the stomach and tapering to become the tail
the tail of the pancreas touches the __
medial side of the spleen
what does the main pancreatic duct dO?
collects the exocrine products of the pancreas and secretes them into the duodenum
the main pancreatic duct fuses with _____
common bile duct
main pancreatic duct empties into the duodenum at the ______
Hepatopancreatic Ampulla of Vater
what percent of the pancreas is exocrine? endorine?
99% exocrine
1% endocrine
what is excreted by the pancreas? what does it do
the enzyme-rich pancreatic juice from the acini also contains bicarbonate ions to neutralize acid from the stomach
the kidneys mark the beginning of the ____ system
urinary
function of kidneys
filter the blood to produce urine
what is the benefit of urine being excreted through a series of tubes and organs?
in this way, the body can get rid of waste and excess ions
what shape are the kidneys? how many
2 - bean-shaped
where are the kidneys located?
lay against the posterior abdominal wall. sit on both sides of the spine at the level of T12 - L2 vertebrae
what size are the kidneys
roughly fist sized
length , width and thickness of the kidneys?
length = 12cm width = 6.5cm thickness = 2.5cm
what is the medial surface of the kidneys called?
the hilum
what occurs at the hilum of the kidneys
this is where the renal arteries and nerves enter and te renal veins and ureters exit
the hilum of the kidneys is continuous with what?
in internal space in each kidney called the renal sinus, which is filled with fatty tissue
what are the two supportive tissues of the kidneys?
- renal capsule (or fibrous capsule)
2. adipose capsule (or perinephric fat)
where is the renal capsule?
covers the outer surface of the kidney
what is the renal capsule composed of?
dense irregular connective tissue
function of the renal capsule
protect and maintain the shape of the kidney
what is the adipose capsule composed of? where is it located?
layer of adipose tissue external to the renal capsule
function of adipose capsule
offers cushion and protection by completely surrounding the kidney
what are the two regions of the kidney?
cortex (outer layer)
medulla (deep to cortex)
extensions of the cortex, called _____ _____ separate the medualla into renal pyramids
renal columns
what divides the kidney into renal lobes?
the renal pyramids
the apex of a renal pyramid is called ____
the renal papilla
a renal lobe consists of what two things?
- a renal pyramid
2. surrounding cortex and renal columns
after urine is produced in the kidneys, where does it flow?
through the renal papilla into a funnel shaped space called the minor calyx
each minor calyx drains into the _____
major calyx
the major calyx drains into the
large renal pelvis, which continues on as the ureter
where do the kidneys get their blood supply?
from the renal arteries, branches off the descending aorta
where do the kidneys drain their blood?
venous drainage of the kidneys is by the renal veins into the inferior vena cava
what are the functional units of the kidney called? what do they do?
nephrons. filter blood and produce urine
how many nephrons are in the kidneys?
millions
the nephron is composed of the ____ and _____
glomerulus and renal tubule
the glomerulus consists of what?
a bunde of capillaries enclosed within the glomerulus capsule
another name for the glomerulus capsule
Bowman’s capsule
what does the glomerulus capsule do?
creates a space between the capillaries and its walls called the capsular (Bowman’s) space
how does filtration occur in the glomerulus?
when the components of the blood are removed from the capillary into Bowman’s space
the material in the Bowman’s space is known as _____
filtrate
what are the two poles of the glomerulus?
- the vascular pole
2. the urinary pole
function of the vascular pole of the glomerulus?
serves as an entry/exit for capillaries within Bowman’s space
function of the urinary pole of the glomerulus
serves as an exit for filtrate into the renal tubule
the capillaries of the glomerulus are ______, (have small holes)
fenestrated
why are the capillaries of the glomerulus fenestrated?
to allow ions, water and other molecules to move through their membranes as filtrate
what are podocytes?
cells surrounding the glomerular capillaries that have filtration slits at their cell junctions to pass the filtrate into Bowman’s space
where can the renal tubule be found?
extends throughout the cortex and medulla of the kidney
how many sections are in the renal tubule?
3
what are the three sections of the renal tubule?
- proximal convoluted tubule
- loop of henle
- distal convoluted tubule
where is the proximal convoluted tubule located?
extends from the urinary pole of the glomerulus and forms a twisted tube in the cortex/medulla of the kidney
what is the role of the proximal convoluted tubule
actively reabsorb all nutrients, ions, vitamins and proteins from the filtrate
where is the loop of Henle located?
projects downwards towards the medulla
what are the two parts of the loop of henle?
- descending limn
2. ascending limb
purpose of the loop of henle?
facilitates reabsorption of water and solutes
where is the distal convoluted tubule located?
extends back up into the cortex and contacts the vascular pole
primary function of the distal convoluted tubule
secrete ions back into the filtrate from the blood
where does the filtrate move after the tubules?
travels into collecting tubes, then collecting ducts that travel within the renal medulla
when can the filtrate be called urine?
once it leaves the collecting duct at the renal papilla
what does the juxtaglomerular apparatus do?
regulates blood pressure of the body by monitoring ion concentrations in the filtrate
what are juxtaglomerular cells
modified smooth muscle cells of the afferent arteroile
what are macula densa?
modified cuboidal cells of the distal convoluted tubule
function of the urinary tract?
transfers and stores the urine produced by the kidneys until it is ready for excretion
what are the three parts of the urinary tract
- the ureters
- the bladder
- the urethra
what are the ureters?
two long, thin, muscular tubes connecting the kidneys with the bladder
where are the ureters located?
begin as a continuation of the renal pelvis and extend downward towards the pelvis where they penetrate the posterior wall of the bladder
the wall of the ureters is made up of how many layers?
3
the mucosa of the ureters is made up of what kind of epithelium?
transitional
the muscularis of the ureters consists of what
two layers of smooth muscle (inner longitudinal and outer circular)
what do the muscles of the ureters do?
propel urine through the ureters
what is the outermost layer of the ureters?
adventitia
what forms the adventitia of the ureters?
loose connective tissue
what does the adventitia of the ureters do?
anchors the ureters to the posterior abdominal wall
what is the urinary bladder?
a muscular, expandable, sac-like pelvic organ that functions in the temporary storage of urine
the interior of the bladder has a ____ appearance
folded
function of rugae in the bladder?
allow the bladder to expand in siz without damage to the mucosa
where if the neck of the bladder located?
constricted. located inferiorly
what is the neck of the bladder attached to?
urethra
the neck of the bladder is surrounded by ____
a sphincter muscle, the internal urethral sphincter
what is the internal urethral sphincter made up of?
smooth muscle
is the internal urethral sphincter under voluntary or involuntary control?
involuntary
where is the bladder located in general?
sits in the pelvic cavity posterior to the pubic bone
where is the bladder located in females?
- posterior to pubic symphysis
- anterior to vagina
- inferior to uterus
where is the bladder located in males
posterior to pubic symphysis
- anterior to rectum
the innermost layer of the bladder wall is lined with
transitional epithelium
what shape are the epithelial cells of the bladder when the the bladder is empty?
dome-shaped
what shape are the epithelial cells of the bladder when the the bladder is full?
stratified squamous
the submucosa of the bladder is made of
dense irregular connective tissue
what function does the submucosa of the bladder serve?
supports the bladder wall during distention, or stretching
what is the detrusor muscle?
the three layers of muscle of the bladder wall
the inner and outer layers of the detrusor muscle are oriented _____, while the middle layer is _____
longitudinally, circular
the outer layer of the bladder wall is ____
adventitia
the adventitia of the bladder does what?
anchors the bladder to surrounding structures
what is the urethra?
a muscular tube connecting the apex of the bladder with the outside world at an opening called the external urethral meatus
the urethra differs in ___ and _____ in males and females
length and position
how long is the female urethra?
3 - 5cm
the female urethra is attached to what?
the anterior wall of the vagina
how is the distance between the external urethral sphincter and the external meatus different in males and females?
closer in females
what is the external urethral sphincter?
skeletal muscle around the urethra within the pelvic floor musculature
is the external urethral sphincter controlled voluntarily or involuntarily?
voluntarily (contracts to hold in urine
in females, the epithelium of the urethra gradually changes from _____ to ______
transitional (near teh bladder) to stratified squamous (near the meatus)
what are the three regions of the male urethra?
- the prostatic urethra
- the membranous urethra
- the penile (spongy) urethra
how long is the prostatic urethra?
3 - 4cm
the prostatic urethra passes through the____
prostate gland
the membranous urethra is between the ____ and the ______
prostate, beginning of penis
how long is the membranous urethra
2cm
the membranous urethra is surrounded by the ____
voluntary external urethral sphincter?
how long is the the penile (spongy) urethra
15cm long through the penis
what kind of epithelium is found in the prostatic urethra?
transitional epithelium
what kind of epithelium is found in the membranous epithelium?
varies from pseudostratified to stratified columnar
what kind of epithelium is found in the penile (spongy) urethra
proximally - pseudostratified to stratified columnar
distally - stratified squamous
in what order does urine flow after the kidneys? (14)
- glomerulus
- Bowman’s capsule
- proximal convoluted tubule
- loop of henle
- distal convoluted tubule
- collecting duct
- renal papilla
- minor calyx
- major calyx
- renal pelvis
- ureter
- bladder
- urethra
- external urethral meatus
the act of urination is called ____?
micturition
how does urination occur?
as the urinary bladder contracts, the external urinary sphincter relaxes to expel urine from the bladder into the urethra, and then outside the body
