Renal System Flashcards
- Which of the following best describes the micturition reflex?
a. Contraction of the external urethral sphincter and relaxation of the detrusor muscle
b. Stretch receptors in the bladder wall sending signals to the brain, initiating a voluntary response
c. Stretch receptors in the bladder wall sending signals to the spinal cord, initiating a parasympathetic response
d. The bladder’s ability to hold urine without any neural input
Answer: c. Stretch receptors in the bladder wall sending signals to the spinal cord, initiating a parasympathetic response
Explanation: The micturition reflex involves stretch receptors in the bladder wall transmitting nerve impulses to the sacral region of the spinal cord, generating a spinal reflex that causes contraction of the detrusor muscle and relaxation of the internal urethral sphincter(PH2130 Micturation).
- What is the glomerular filtration rate (GFR) and its importance?
a. The amount of urine produced per hour; it indicates the kidney’s filtration capacity
b. The rate at which the kidneys filter blood; crucial for removing waste and maintaining homeostasis
c. The amount of blood flowing through the kidneys per minute; essential for blood pressure regulation
d. The pressure exerted by blood on the walls of the glomerulus; important for maintaining filtration pressure
Answer: b. The rate at which the kidneys filter blood; crucial for removing waste and maintaining homeostasis
Explanation: GFR, typically around 125 mL/min or 180 liters/day, is crucial for the removal of waste and maintaining the body’s fluid and electrolyte balance. It is regulated by various factors including blood pressure and renal blood flow(Renal System Filtration…)(Renal System (structure).
- Which nerves are involved in the control of urination?
a. Vagus, hypogastric, and pelvic
b. Hypogastric, pelvic, and pudendal
c. Sciatic, pudendal, and hypogastric
d. Pelvic, sciatic, and vagus
Answer: b. Hypogastric, pelvic, and pudendal
Explanation: The control of urination involves the hypogastric nerve, which suppresses detrusor contraction, the pelvic nerve, which activates detrusor contraction, and the pudendal nerve, which controls the external urethral sphincter(PH2130 Micturation).
- What are the primary processes of the kidneys involved in urine formation?
a. Filtration, reabsorption, secretion, and excretion
b. Filtration, diffusion, osmosis, and excretion
c. Reabsorption, secretion, elimination, and diffusion
d. Secretion, excretion, filtration, and osmosis
Answer: a. Filtration, reabsorption, secretion, and excretion
Explanation: The kidneys produce urine through four major processes: filtration (movement of water and solutes from blood into the nephron), reabsorption (returning essential substances to the blood), secretion (adding additional wastes to the filtrate), and excretion (eliminating the final urine)(PH2130 Renal System Ove…).
- Which statement about the structure and function of nephrons is correct?
a. Each nephron filters approximately 10 liters of blood per day
b. The nephron’s primary function is to secrete hormones
c. Nephrons are the functional units of the kidney responsible for filtering blood and forming urine
d. Nephrons do not play a role in regulating blood pressure
Answer: c. Nephrons are the functional units of the kidney responsible for filtering blood and forming urine
Explanation: Nephrons, numbering about 2 million in the kidneys, are the functional units responsible for filtering blood, reabsorbing necessary substances, secreting wastes, and forming urine(Renal System (structure)(PH2130 Renal System Ove…).
- Which factor primarily drives glomerular filtration?
a. Oncotic pressure in the Bowman’s capsule
b. Hydrostatic pressure in the glomerular capillaries
c. Osmotic pressure in the distal convoluted tubule
d. Hydrostatic pressure in the renal pelvis
Answer: b. Hydrostatic pressure in the glomerular capillaries
Explanation: Glomerular filtration is primarily driven by the hydrostatic pressure in the glomerular capillaries, which forces fluid and solutes out of the blood and into the Bowman’s capsule(Renal System Filtration…).
- Which of the following hormones regulate sodium reabsorption in the distal convoluted tubule?
a. Aldosterone and vasopressin
b. Renin and erythropoietin
c. Calcitonin and parathyroid hormone
d. Adrenaline and noradrenaline
Answer: a. Aldosterone and vasopressin
Explanation: Sodium reabsorption in the distal convoluted tubule is regulated by aldosterone, which increases sodium reabsorption, and vasopressin (ADH), which also promotes water reabsorption(Renal Tubule (2)).
- What is the primary function of the proximal convoluted tubule in the nephron?
a. Filtration of blood
b. Bulk reabsorption of water, glucose, amino acids, and electrolytes
c. Secretion of hormones
d. Formation of concentrated urine
Answer: b. Bulk reabsorption of water, glucose, amino acids, and electrolytes
Explanation: The proximal convoluted tubule is responsible for the bulk reabsorption of water, glucose, amino acids, and electrolytes from the filtrate back into the blood(Renal Tubule (2)).
- Which structure in the kidney is primarily responsible for the counter-current multiplier effect?
a. Proximal convoluted tubule
b. Loop of Henle
c. Distal convoluted tubule
d. Collecting duct
Answer: b. Loop of Henle
Explanation: The Loop of Henle is responsible for the counter-current multiplier effect, which creates a concentration gradient in the medulla, allowing for the production of concentrated urine(Renal Tubule (2)).
- Which of the following best describes the role of the ureters in the urinary system?
a. Storage of urine
b. Filtration of blood
c. Transport of urine from the kidneys to the bladder
d. Regulation of blood pressure
Answer: c. Transport of urine from the kidneys to the bladder
Explanation: The ureters are responsible for transporting urine from the kidneys to the bladder through peristaltic contractions(PH2130 Renal System Ove…).
- Which of the following best describes the role of aquaporins in the renal system?
a. They transport ions across the cell membrane
b. They are involved in the reabsorption of glucose
c. They facilitate water movement across cell membranes
d. They secrete waste products into the tubule
Answer: c. They facilitate water movement across cell membranes
Explanation: Aquaporins are specialized channels in cell membranes that facilitate the movement of water across cells, playing a crucial role in water reabsorption in the kidneys【13†source】.
- Which part of the nephron is primarily responsible for the filtration of blood?
a. Proximal convoluted tubule
b. Loop of Henle
c. Glomerulus
d. Collecting duct
Answer: c. Glomerulus
Explanation: The glomerulus is a network of capillaries in the nephron that filters blood to form a filtrate, which will be processed to form urine【14†source】.
- Which hormone is primarily responsible for increasing water reabsorption in the kidneys?
a. Aldosterone
b. Antidiuretic hormone (ADH)
c. Renin
d. Erythropoietin
Answer: b. Antidiuretic hormone (ADH)
Explanation: Antidiuretic hormone (ADH), also known as vasopressin, increases the permeability of the distal convoluted tubule and the collecting duct to water, promoting water reabsorption【12†source】【13†source】.
- Which component of the renal system directly regulates blood pH?
a. Proximal convoluted tubule
b. Distal convoluted tubule and collecting duct
c. Glomerulus
d. Loop of Henle
Answer: b. Distal convoluted tubule and collecting duct
Explanation: The distal convoluted tubule and the collecting duct are involved in the regulation of blood pH by controlling the excretion of hydrogen ions and the reabsorption of bicarbonate【13†source】.
- Which of the following best describes the function of erythropoietin produced by the kidneys?
a. Regulation of sodium reabsorption
b. Stimulation of red blood cell production
c. Regulation of calcium levels
d. Conversion of vitamin D to its active form
Answer: b. Stimulation of red blood cell production
Explanation: Erythropoietin, produced primarily by the kidneys, stimulates the production of red blood cells in the bone marrow in response to low oxygen levels【11†source】.
- What is the primary function of the Loop of Henle in the nephron?
a. Filtration of blood
b. Reabsorption of glucose
c. Creation of a concentration gradient in the medulla
d. Secretion of hormones
Answer: c. Creation of a concentration gradient in the medulla
Explanation: The Loop of Henle creates a concentration gradient in the renal medulla, which is crucial for the kidney’s ability to produce concentrated urine
- Which of the following is NOT a function of the kidneys?
a. Regulation of blood volume and pressure
b. Regulation of electrolyte balance
c. Production of digestive enzymes
d. Regulation of blood pH
Answer: c. Production of digestive enzymes
Explanation: The kidneys do not produce digestive enzymes; they are involved in the regulation of blood volume and pressure, electrolyte balance, and blood pH
- Which structure collects urine from the nephrons and funnels it into the ureter?
a. Glomerulus
b. Proximal convoluted tubule
c. Renal pelvis
d. Loop of Henle
Answer: c. Renal pelvis
Explanation: The renal pelvis collects urine from the nephrons and funnels it into the ureter for transport to the bladder【14†source】.
- Which of the following is a major component of the renal corpuscle?
a. Distal convoluted tubule
b. Collecting duct
c. Bowman’s capsule
d. Loop of Henle
Answer: c. Bowman’s capsule
Explanation: The renal corpuscle consists of the glomerulus and Bowman’s capsule, where blood filtration begins【14†source】.
- Which pressure opposes filtration in the glomerulus?
a. Hydrostatic pressure in the glomerular capillaries
b. Hydrostatic pressure in Bowman’s capsule
c. Oncotic pressure in the glomerular capillaries
d. Hydrostatic pressure in the renal artery
Answer: b. Hydrostatic pressure in Bowman’s capsule
Explanation: The hydrostatic pressure in Bowman’s capsule opposes the filtration pressure created by the hydrostatic pressure in the glomerular capillaries【10†source】.
- Which hormone increases sodium reabsorption in the nephron?
a. Vasopressin
b. Erythropoietin
c. Aldosterone
d. Renin
Answer: c. Aldosterone
Explanation: Aldosterone increases sodium reabsorption in the nephron, particularly in the distal convoluted tubule and collecting duct【13†source】.
- Which part of the nephron is primarily responsible for the reabsorption of glucose?
a. Loop of Henle
b. Proximal convoluted tubule
c. Distal convoluted tubule
d. Collecting duct
Answer: b. Proximal convoluted tubule
Explanation: The proximal convoluted tubule is responsible for the bulk reabsorption of glucose, amino acids, and other essential nutrients from the filtrate back into the blood【13†source】.
- What role does the juxtaglomerular apparatus play in kidney function?
a. Filtration of blood
b. Secretion of renin to regulate blood pressure
c. Reabsorption of water
d. Regulation of calcium levels
Answer: b. Secretion of renin to regulate blood pressure
Explanation: The juxtaglomerular apparatus secretes renin, which is involved in the regulation of blood pressure through the renin-angiotensin-aldosterone system
- Which of the following is true about the renal medulla?
a. It contains the glomeruli
b. It is involved in the filtration of blood
c. It contains the loops of Henle and collecting ducts
d. It is responsible for the secretion of erythropoietin
Answer: c. It contains the loops of Henle and collecting ducts
Explanation: The renal medulla contains the loops of Henle and collecting ducts, which play a crucial role in creating the osmotic gradient necessary for water reabsorption【13†source】.