Renal Physiology Flashcards
(34 cards)
What is the role of the kidneys in the body?
The kidneys are vital excretory organs that maintain homeostasis by processing blood plasma, removing waste, and adding necessary substances.
What is the approximate size and weight of an adult human kidney?
Each kidney weighs about 150 grams and is about the size of a clenched fist.
Describe the pathway of urine from its formation to excretion.
Urine flows from the kidneys → ureters → bladder → urethra.
How do kidneys maintain homeostasis?
• By processing blood plasma
• Removing substances (e.g., waste)
• Adding substances (e.g., ions and water)
List the main functions of the kidneys.
• Regulate water concentration and fluid volume
• Control inorganic ion levels and acid-base balance
• Excrete metabolic waste
• Eliminate foreign chemicals and drug metabolites
• Generate glucose via gluconeogenesis (during fasting)
• Release hormones like erythropoietin, renin, and 1,25-dihydroxyvitamin D
What is the approximate size and weight of an adult human kidney?
Each kidney weighs about 150 grams and is about the size of a clenched fist.
What hormones do the kidneys produce?
Erythropoietin, renin, and 1,25-dihydroxyvitamin D.
What are the two main regions of the kidney?
The outer renal cortex and the inner renal medulla.
What is a nephron, and how many are in each kidney?
A nephron is the functional unit of the kidney; each kidney contains about 1 million nephrons.
Can kidneys regenerate new nephrons?
No, kidneys cannot regenerate new nephrons.
What is a nephron, and how many are in each kidney?
A nephron is the functional unit of the kidney; each kidney contains about 1 million nephrons.
What happens to nephrons with age?
After age 40, the number of functioning nephrons decreases by about 10% every 10 years.
What are the two main parts of each nephron?
The renal corpuscle and the renal tubule.
What structures make up the renal corpuscle?
The glomerulus and Bowman’s capsule.
What is the glomerulus?
A tuft of interconnected glomerular capillaries where large amounts of fluid are filtered from the blood.
What surrounds the glomerular capillaries?
Epithelial cells and Bowman’s capsule.
What structures make up the renal corpuscle?
The glomerulus and Bowman’s capsule.
Which arteriole supplies blood to the glomerulus?
Afferent arteriole.
Through which arteriole does blood leave the glomerulus?
Efferent arteriole.
What does the renal corpuscle filter out from blood?
Cells, large polypeptides, and proteins—forming a filtrate free of these components.
What happens to the filtrate after it leaves the renal corpuscle?
It enters the renal tubule, where it is modified and eventually becomes urine.
What is the structure of the renal tubule?
narrow tube made of a single layer of epithelial cells on a basement membrane, which varies in structure and function along its length.
What is the first part of the renal tubule?
The proximal tubule.
After the proximal tubule, where does the fluid flow?
Into the loop of Henle.
