Urinary System Flashcards
What does urinary system accomplish?
- maintain composition, pH and volume of body fluid
- excretes foreign substances
What structures make up urinary system?
pair of kidneys, ureters, urinary bladder and urethra
What is the basic function of the kidneys
remove substances from the blood and secrete certain hormones
What serves as a urine reservoir?
urinary bladder
Is the kidney enclosed in a capsule?
yes a tough, fibrous, capsule
The left kidney is higher/the same/lower than the right kidney
left is a bit higher
Kidneys are positioned:
retroperitoneally
What holds kidneys in place?
connective tissue and adipose tissue
The main function of the kidneys is to:
regulate the volume and composition of body fluids
The kidneys also contribute to RBC formation by secreting:
EPO
The kidneys contribute to blood pressure by releasing:
renin
Kidneys regulate absorption of calcium ions by activating:
vitamin D
The medical technology that can take over the role of the kidneys is known as:
hemodialysis
Concave medial surface of the kidney is called:
renal sinus
The entrance to the sinus (where blood vessels, nerves and lymphatic vessels pass) is called the:
hilum
The superior end of the ureter forms the, in other words this structure directs urine towards the ureter, it pretty much becomes the ureter:
renal pelvis
The renal pelvis is formed by the convergence of 2 or 3 tubes called:
major calyces
Major calyces are formed by the convergence of:
7-20 minor calyces
At least one small projection called a _________ extends into each minor calyx
renal papilla
The kidney includes 2 distinct regions. Name them:
inner medulla and an outer cortex
Renal medulla is made up of:
renal pyramids
What is the tissue of the renal medulla like?
striated with microscopic tubules
The granular shell around the renal medulla is the:
renal cortex
What are the subunits of the kidneys?
nephrons
How many nephrons are there? And what are they responsible for?
- 1 million
- urine formation
What does each nephron consist of?
renal corpuscle
renal tububle
The renal arteries arise from the:
abdominal artery
When at rest the renal arteries usually carry what percentage of total cardiac output to the kidneys?
15-30%
Arteries enter kidney through:
hilum
What is the pathway of arteries in the kindey:
interlobar - arcuate arteries - cortical radiate arteries - afferent arterioles - nephrons - glomerulus (within renal corpuscle) - efferent arterioles - peritubular capillaries
What are parellel bundles of blood vessels that descend and then ascend in the kindeys?
vasa recta
What kidney vein joins the inferior vena cava back to the heart?
renal vein
AGAIN, what does each nephron consist of?
renal corpuscle, renal tubule
A renal corpuscle contains what structure?
glomerulus and glomerular capsule. Afferent leads to glomerulus and then efferent goes out.
The first step of urine formation is filtration of fluid from the:
glomerular capillaries
The glomerular capsule is composed of 2 epithelial layers:
- visceral - podocytes
2. parietal - squamous
So kidneys filter blood. Blood comes in from the renal artery and the rest of the pathway to the glomerulus and then filtered material goes on to the ___________ then the nephron loop and the __________.
- proximal convoluted tubule
2. distal convoluted tubule
The distal convoluted tubule merge in the renal cortex to form a:
collecting duct
Is there 1 collecting duct per nephron?
no, 1 collecting duct drains several nephrons
The collecting duct passes into the __________ widening as it joins other collecting ducts.
renal medulla
As the collecting ducts merge they form a larger tube that empties into a ______.
minor calyx through an opening in a renal papilla
So in summary what are the parts of nephron?
glomerulus, glomerular capsule, proximal convoluted tubule, nephron loop (ascending and descending) distal convoluted tubule
What is associated with urine formation and nephron but not a part of a nephron?
collecting duct
The first structure of urine excretion is:
minor calyx
From the minor calyx where does urine go?
- major calyx - renal pelvis - ureter - urinary bladder and urethra
What is a cortical nephron?
most nephrons have renal corpuscles in the renal cortex near the surface of the kidney. so most nephrons are cortical nephrons
What are juxtamedullary nephrons?
corpuscles deep in the cortex close to the renal medulla
What is the juxtaglomerular apparatus:
nephron loop comes back up to touch the glomerulus. Where it touches the glomerulus the cells of the ascending loop are tall and dense epithelial cells called macula densa
2. ALSO includes juxtaglomerular cells
What are juxtaglomerular cells?
smooth muscle cells near afferent arteriole that associate with the macula densa
What does the juxtaglomerular apparatus have a role in:
renin secretion
What does urine contain? a - water b - nitrogenous wastes c - electrolytes d- all of the above
d - all of the above
Name the 3 steps of urine filtration:
- glomerular filtration
- tubular reabsorption
- tubular secretion
Glomerular filtration involves:
filtering plasma of blood
What force leads to filtering:
blood pressure (hydrostatic pressure)
What force leads to reabsorption:
colloid osmotic pressure
Nephrons use ______ capillary beds. The first bed is only to filter.
2
Filtered fluid from glomerular filtration:
tubular fluid
Most of filtered fluid is
a. returned to the body
b. excreted as urine
c. both are even
a. returned to the body
Fluid is returned to the internal environment through:
tubular reabsorption
The final stage or urine excretion is _________, where substances are eliminated faster than filtration alone.
tubular secretion
During glomerular filtration __________ are filtered out leaving ________.
water and other small dissolved molecules
- large proteins
Glomerular capillaries are more permeable to small molecules due to many tiny openings called:
fenestrae
What structure receives the resulting glomerular filtrate?
glomerular capsule
So what is contained in glomerular filtrate?
water, urea, amino acids, uric acid, creatine, creatinine, sodium, chloride, potassium, calcium, bicarbonate, phosphate and sulfate ions
What has larger diameter:
afferent arterioles, which causes backup of blood to back up in the glomerulus, raising blood pressure in the glomerular capillaries
the plasma colloid osmotic pressure is always ________ than that of the glomerular filtrate and since there are more proteins in the plasma and this draws shit back in.
higher
the result of all forces is called the _________
and it is usually _____, favoring filtration/reabsorption.
- net filtration pressure
- +10
- filtration
The GFR is directly proportional to the __________
net filtration pressure
The most commonly measured index of kidney function is:
GFR
If the efferent arteriole constricts what happens to filtration:
increased filtration
The force favoring filtration/reabsorption is always predominant
filtration
Lowering plasma protein concentration (in plasma so thus in the capillaries) would have what effect on filtration rate?
increase filtration (more fluid since less proteins - therefore more fluid would leave from high to low)