Exam I Renal Flashcards
4 components of the urinary system:
- Kidneys
- Ureters
- Urinary Bladder
- Urethra
Which of the following are functions of the kidney?
a. Maintaining constant ECF
b. Elimination of wastes
c. Acid-Base balance
d. Glucose synthesis
e. Synthesis of hormones
f. All of the above
f. all of the above
List the 7 functions of the kidneys:
- Filtration of blood
- Production of urine
- Reabsorption of filtered substances
- Excretion of metabolic wastes and xenobiotics
- Water and acid-base balance
- Production of glucose
- Endocrine functions
Which of the following clinical signs may be associated with a chronic renal failure?
a. Presence of urine sediments
b. inc. urine specific gravity
c. Pale mucous membranes
d. Polydipsia
e. All of the above
c. Pale mucous membrane
What are 3 important hormones produced by the kidney?
- Calcitriol
- Renin
- Erythropoietin
What hormone stimulates the production of Calcitriol?
PTH
Calcitriol secreted in response to ________
Hypocalcemia
Why is renin an important hormone secreted by the kidney?
regulation of blood pressure
Why is erythropoietin an important hormone secreted by the kidney?
essential for erythropoiesis
What are the 2 types of nephrons?
- Cortical nephrons
2. Juxtamedullary nephrons
2 characteristics of cortical nephrons:
- short loops of henle
2. supplied by peritubular capillaries
3 characteristics of juxtamedullary nephrons
- located near medulla
- vasa recta
- long loops of henle
Structure of the nephron located in the renal cortex, consists of glomerulus surrounded by bowman’s capsule
Malpighian body
The longest part of the nephron, consisting of PCT and a straight part
Proximal tubule
What are the 4 limbs of the loop of Henle
- Thick Descending limb
- Thin Descending limb
- Thin Ascending limb
- Thick Ascending limb
Which portion of the loop of henle extends into the renal medulla?
Thick Descending Limb
Which portion of the loop of henle is only found in juxtamedullary nephrons?
Thin Ascending Limb
What are the 2 parts of the distal tubule of the nephron?
Straight and convoluted part
Structure of the nephron that extends through the renal cortex and medulla
Collecting Duct (CD)
What percentage of cardiac output goes into the kidney?
25%
The top one cause of death in humans worldwide is:
a. HIV/AIDS
b. Road Traffic Accidents
c. Cancer
d. Myocardial Infarction
d. Myocardial Infarction
Interruption of blood supply to a tissue
Ischemia
Re-establishment of blood supply to a tissue
Reperfusion
What are 4 main causes of renal IR?
- Organ transplant
- Cardiac and vascular surgeries
- Acute renal failure
- Toxins
Highly reactive molecules that damage DNA, lipids, and proteins
Reactive O2 Species (ROS)
What causes an inc. in ROS in the kidneys?
Inflammatory response and O2 deprivation
usually ischemia
Which of the following statements concerning the structure of the nephron is NOT correct?
a. The PCT is located in the cortex
b. Thin limbs of Henle’s loop are located in the medulla
c. The collecting Ducts extend through the renal cortex and medulla
d. The Macula Densa is located in the outer medulla
d. The Macula Densa is located in the outer medulla
located in the cortex
What are the 4 main processes in the kidneys?
- Filtration
- Re-absorption
- Secretion
- Excretion
How much of the glomerular filtrate is excreted as urine?
a. 20%
b. 10%
c. 1-5%
d. Less than 1%
d. Less than 1%
Which of the following structures is NOT a component of the filtration barrier?
a. Capillary endothelium
b. Bowman’s capsule
c. Podocytes
d. Glomerular BM
b. Bowman’s Capsule
What is the 1st step of urine formation?
Filtration through glomerular capillaries into Bowman’s Capsule
Fluid produced by the glomerulus that is nearly identical to the plasma
Glomerular Filtrate
The rate the kidney is perfused with blood
Renal Plasma Flow (RPF)
The Rate of glomerular filtration depends on ______.
RPF
What percentage of blood plasma flowing through the kidney is filtered through the glomeruli?
20%
A network of branching and anastomosing capillaries covered by podocytes and encased in bowman’s capsule
Glomerulus
The area b/t glomerular capillaries and bowman’s capule
Bowman’s space
What are the 3 components of the filtration barrier?
- Capillary endothelial cells
- Glomerular BM
- Visceral epithelium (podocytes)
what type of junctions are found b/t capillary endothelial cells?
Fenestrated
What are the 3 layers of BM of capillaries?
- Lamina rara interna
- Lamina densa
- Lamina rara externa
Which layer of the capillary BM contains the most proteins?
middle, Lamina Densa
T/F. Glomerular capillaries are highly permeable to Proteins
F. Relatively impermeable
The higher the molecular weight of a substance, the ______ the filterability.
Lower
T/F Electrolytes and small organic compounds are filtered as freely as water?
T
Filterability through the glomerulus is dependent of what factors:
- Size
- Electrical charge
- Plasma protein binding
T/F. Anionic substances are more filtered than Cationic
F. Cationic are more filtered
The main driving force for filtration in the glomerulu sis:
a. the oncotic pressure of the blood
b. the hydrostatic pressure of the blood
c. the oncotic pressure in Bowman’s capsule
d. The hydrostatic pressure in Bowman’s Space
b. Hydrostatic pressure of the blood
What are the 2 forces opposing filtration ?
- The hydrostatic pressure in bowman’s space
2. the oncotic pressure of the blood plasma
T/F. the oncotic pressure of the filtrate is nonexistent
T
The total volume of fluid filtered by the glomeruli into Bowman’s Space per Kg.
GFR
What are the nessecary properties of GFR indicator substances?
- Must be freely filterable
- filtered amt. must not change due to resorption or secretion
- must not be metabolized in the kidney
- must not alter renal function
the rate the plasma is cleared of a substance, if the substance is free filterable
GFR
If creatine in plasma is elevated, then GFR is inc/dec?
Dec.
Percentage of the plasma that has been filtered by the glomeruli
Fraction of Filtration (FF)
Where is renin produced?
in the wall of cells located in the afferent arterioles
What are 2 types of autoregulatory mechanisms for blood flow?
- Myogenic reflex
2. Tubuloglomerular feedback
What is the myogenic reflex?
Detects changes in glomerular perfusion
What is the tubuloglomerular feedback?
Detects changes in tubule fluid delivery
T/F. Aldosterone is produced by cells of the renal medulla?
F. Adrenal cortex
List the 2 vasodilatory agents from class.
- No
2. PGE2
List the 3 Constricting factors from class.
- Endothelin
- TXA2
- ANG2
If you inc. RBF, GFR will inc/dec.
inc
If systemic pressure inc. then GFR will inc/dec.
inc