Lecture Test One Part Two Flashcards
What are the two parts of the small intestine?
cecum
Colon
What is the cecum?
a blind pouchright after the ileocecal valve
What is attached to the cecum?
vermiform appendix
How long is the cecum?
2.5 inches
What are the symptoms of appendicitis?q
pain, nausea, vomitting and fever
What are the 4 subdivisions of the colon?
ascending colon
transverse colon
descending colon
sigmoid colon
What is the teniae coli?
bands of longitudal muscle fibers
What is significant of the tunica muscularis of the colon?
it is not complete
What are haustra?
individual pouches
What is the rectum?
a straight muscular tube
what is significant of the tunica muscularis of the rectum?
It is thicker than other parts of the digestive tract
what is significant of the tunica muscularis of the anal canal?
It is even thicker than the muscularis of the rectum
The internal sphincter of the anal canal is
snvoluntary smooth muscle
The external sphincter of the anal canal is
voluntary skeletal muscle
Children should not be expected to have control over bowels movement until 1 year of age because
the external sphincter takes time to develop
what are hemorrhoids?
veins of the anal canal become enlargedand inflammed and can burst
who is most likely to be affected by hemorrhoids?
pregnant people and those who are often constipated
What mechanical digestion is found in the large intestine?
haustral churning
peristalsis
what is haustral churning?
haustra remain relaxed as the chyme fills them up. When distended the walls contract and fill the next haustrum
What is significant of peristalsis of the large intestine?
they are called mass movements
what are mass movements?
strong contractions occurring over a large portion of the colon
what is an example of a mass movement?
gastrocolic reflex
what is a gastrocolic reflex?
forceful contractions that begin in the middle of the transverse colon and pushes chyme into the rectum
What causes secretions in the large intestine?
bacteria
The bacteria in the large intestine will breakdown any remaining
proteins into amino acids
What causes the odor of feces?
further breakdown of amino acids into indoles and skatoles
bacteria of the small intestine will ferment some ______ into gases causing flatulence
carbohydrates
What does a person gain from E Coli?
some b vitamins bust mostly vitamin K
What is vitamin K important for?
blood clotting
Newborns are not born with E. Coli in the digestive tract so they
receive injections
How long do bacterial populations take to populate?
1 week
What absorption occurs in the large intestine?
mostly water
Chyme remains in the large intestine for how long?
18-24 hours
Why are feces solid?
because water is absorbed back into the body
What do feces consist of?
water salts epithelial cells from GI tract bacteria fiber
Peristalsis moves fecal matter into the rectum where
there is distention of the walls and therefore stimulation of the stretch receptors. The impulse travels to the brain and the person has the urge to defecate
Does ingestion occur in the large intestine?
no
does secretion occur in the large intestine?
yes
Does motility occur in the large intestine?
yes
Does elimination occur in the large intestine?
yes, feces
What chemical digestion occurs in the large intestine?
E.Coli
The primary function of the urinary system is to
maintain homeostasis
how does the urinary system maintain homeostasis?
controls volume, pH and concentration of blood regulates RBC production getting rid of waste regulating blood pressure Vitamin D synthesis
what does vitamin D synthesis do?
helps regulate calcium levels
what are the organs of the urinary system?
2 kidneys
2 ureters
1 urinary bladder
1 urethra
Why is the right kidney lower than the left kidney?
the liver
How much kidney is needed to maintain homeostasis?
1/3
What do kidneys look like?
reddish brown, size of a clenched fist
where are the kidneys located?
either side of the spinal column in retroperitoneal position
what are the three layers of the kidney?
renal fascia
adipose capsule
renal capsule
what is the outside region of the kidney called?
cortex
what is nephrotosis?
floating kidney, the kidney drops down
why does nephrotosis occur?
very thin people with little adipose
what does nephrotosis cause?
a kink in the ureter which blocks urine flow
what is the outer layer of th ekidney called?
medulla
the medulla contains
pyramids
the pyramids contain
papillae
the papillae extend into
major calices
the major calyces join to form a
renal pelvis
the pelvis narrows to exit the
hilum as the ureter
what is a nephron?
the functional unit of the kidney
how many nephrons are in one kidney?
1.3 million
what are the 2 componenets of the renal corpuscle?
glomerulus
Bowman’s capsule
the renal tubule consists of
a proximal convoluted tubule
loop of henle
distal convuluted tubule
collecting duct
the number of nephrons at birth
are constant, they will not be replaced
existing nephrons are often able to
increase their filtration to make up for loss of nephrons
Urine is
the fluid that is produced by the kidneys that contains waste or excess materials
what are the three processes of the nephron that form urine?
glomular filtration
tubular reabsorption
tubular secretion
Where does glomerular filtration occur?
renal corpuscle
What composed the renal corpuscle?
glomerulus and the Bowman’s capsule
What is the glomerulus?
A tuft of capillaries which is closely associated with Bowman’s capsule
Bowman’s capsule is indented to form
a double layered chamber
The outer wall of Bowman’s capsule is called the
parietal layer
the inner portion of Bowman’s capsule is called the
visceral layer
The visceral layer is composed of
podocyte cells
Podocyte cells wrap around
glomerular capillaries
what is glomerular filtration rate?
the amount of filtrate produced each minute
How does blood enter the glomerulus?
afferent arteriole
what is an afferent arteriole?
small blood vessel
During glomerular filtration, blood forces some water and dissolved solutes from the blood through the pores of
the capillaries and through the filtration slits of Bowman’s capsule
What is filtrate?
what urine derives from
what does filtrate consist of?
wastes plus solutes that are valuable and need to be returned to the body
blood gets taken away from the glomerulus by way of
the efferent arteriole
The formation of filtrate depends upon
filtration pressure being high enough
To help in pressure formation, the efferent arteriole has a _____________ than the afferent arteriole
smaller lumen
what is tubular reabsorption?
movement of certain substances from the filtrate back into the blood.
why does tubular reabsorption occur?
the anatomical placement of blood vessels. peritubular vessels close to the nephron
99% of the components of the filtrate during tubular reabsorption
are released back into the blood
what are the components of the filtrate during tubular reabsorption?
water, glucose, amino acids and some ions
What is the major site of tubular reabsorption?
PCT
What are the four transport methods used in tubular reabsorption?
active transport
secondary active transport
facilitated diffusion
osmosis
During tubular reabsorption, where sodium goes,
water follows
During tubular reabsorption, no ___________ are involved
hormones
what substances are reabsorbed into the blood by the PCT
sodium potassium chloride glucose amino acids
When sodium ions are transported back into the blood,
water follows decreasing the volume of filtrate and increasing the volume of blood
what is obligatory water reabsorption?
the body has no control how much water is absorbed in the PCT–no hormonal regulation
The PCT is always
permeable to water
Potassium, chloride and urea will leave the PCT by
facilitated diffusion
glucose molecules will enter the PCT by
cotransport
glucose molecules will leave the PCT by
facilitated diffusion
Why is there a maximum amount of glucose that can be transported in a given amount of time?
Because there is a specific amount of transporters in the membrane of the PCT
If there is a large amount of glucose in the urine,
it will exceed the amount of transporters and glucose remains in the filtrate.
How do you test for diabetes mellitus?
urine sample. Before lab tests, people had to taste it
During tubular reabsorption, most amino acids are reabsorbed by
facilitated diffusion
What is the Loop of Henle?
The secondary site for tubular reabsorption
What is the final result of tubular reabsorption?
movement of water from the nephron into the blood
The loop of henle dips into
the medulla of the kidney
the concentration of solutes around the loop of henles in the interstitial fluid is
very high
the hypertonic environment of the loop of henle results in
more water leaving the loop and returning to the blood decreasing the volume of the filtrate
what are the vasa recta?
blood vessels arounf the loop of henle that receive the water during tubular reabsoortion
what are the two regions of the loop of henle?
ascending
descending
why does reabsorption occur in the descending region?
because the ascending region is impermeable to water
After leaving the Loop of Henle, the filtrate continues to the
Distal convoluted tubule and finally to the collecting duct. where more water absorption will occur
Reabsorption in the DCT will be under control by
antidiuretic hormone
aldesterone
A diuretic is something that will increase
the amount of urine
How do diuretics work?
they increase the amount of water that leaves the filtrate causing more urine to be produced.
What are some natural diuretics?
caffeine
alcohol
What is ADH?
a hormone that decreases the amount of urine
How does ADH work?
increases the permeability of the membranes of the DCT and collecting duct leading to more water being absoprbed into the blood
ADH is produced by
the hypothalamus
ADH is released by
the posterior pituitary gland
What is the stimulus for release of ADH
hypotension
What is the target organ of ADH?
kidneys
What is the result of the release of ADH?
increases the permeability of water causing less urine to be produced
what is the pathway for ADH?
ADH travels through the blood and to the kidneys. Increases permeability of DCT and CD to water. Increases H20 reabsorption into the blood. Increases amount of water in blood. Increases blood pressure
The pathway of ADH is an example of
falcutative water reabsorption
What is falcutative water reabsorption?
Permeability of membranes of DCT and CD to water will change according to the body’s need
what is diabetes insipidus?
hyposecretion of ADH
what are symptoms of diabetes insipidus?
massive amount of uriniation leading to dehydration and thirst
Is diabetes insipidus life threatening?
yes
What is the treatment for diabetes insipidus?
exogenous ADH
Exogeneous is also helpful with
children bedwetting
How is exogeneous ADH given
nose spray
How does alcohol have an effect on urination?
suppresses the release of ADH and leads to frequent urination
what is renin-angiotension-aldosterone?
hormonal reaction that is stimulated by hypotension
what is the outcome of renin-angiotension-aldosterone?
increases the amount of H20 that is reabsorbed in the DCT and CD and increases blood volume
what is atrial naturiuretic hormone?
hormone that prevents sodium reabsorption in the kidney tubules and inhibit ADH secretion
who secretes atrial naturiuretic hormone?
cardiac muscle cells in the right atrium of the heart
what is the result of the release of atrial naturiuretic hormone?
more sodium and water are excreted with a decrease in blood volume and an increase in urine volume.
what is the pathway to aldosterone secretion?
Renin Angiotensiongen angiotension 1 angiotension 2 ADH aldosterone
what is tubular secretion?
removal of materials not needed by the body
what is one of the most important substances secreted during tubular secretion?
hydrogen
why is hydrogen secretion important?
hydrogen affects pH of the blood
the higher the concentration of Hydrogen,
the lower the pH of the blood
The secretion of hydrogen occurs into
the renal tubules, primarily the PCT and DCT
Tubular secretion is classified as
countertransport
Once tubular secretion occurs,
urine is formed
what is the main concern with ureters?
kidney stones
how does urine pass through the ureters?
peristalsis and gravity
from the ureters, urine moves to the
urinary bladder
what is the function of the urinary bladder?
to store urine until micturation
what is micturition?
urination
what is the urinary bladder?
hollow organ with stratified transitional epithelium for stretching
what is a trigone?
a smooth triangular region of the urinary bladder
what forms the trigone?
openings of the two ureters and the urethra
when there is a small amount of urine in the bladder, the walls
are in folds called rugae
when the bladder is full, it is
pear-shaped and the rugae are stretched
what is incontinence?
loss of control of urination
urine is stored in the urinary bladder until
micturition is convenient
the awareness to urinate is stimulated by
the fullness of the bladder and stimulus of stretch receptors in the bladder walls
Stretch receptors send
an impulse to the brain and the person becomes aware of the need.
what is the urethra?
tube leading from the floor of the urinary bladder to the exterior.
In males, the urethra is
longer and is also used for transportation of sperm
when a person has insufficient numbers of nephrons to maintain homeostasis
renal failure occurs
what is the treatment for renal failure?
dialysis
what is dialysis?
Cleansing the body of waste products
what are the two types of dialysises?
hemodialysis
Continuous ambulatory peritoneal dialysis
what is hemodialysis?
artificial kidney machine filters blood through selectively permeable tubing. Waste products diffuse from the blood into the solution that surrounds the tube.
how many times do you use hemodialysis?
2-3 times per week
what must you have for hemodialysis?
a concentration gradient
what is continuous ambulatory peritoneal dialysis?
sterile dialysis solution is inserted into the cavity through a tube that has been surgically placed.
what does renal failure ultimately affect?
erythropoietin is gone affecting RBC production
what is ketoacidosis?
condition that occurs in people with diabetes mellitus that causes increased acidity in the blood
what are the symptoms of ketoacidosis?
fruity breath
rapid breathing
what compartment hold the most fluid?
intracellular fluid compartment
what are ulcers?
deep erosions of the lining of the stomach mucosa
what is the main cause of ulcers?
NSAIDs like aspirin and bacterial infections
what is a complication of ulcers?
perforation