High School Biology : Understanding Nephron Function
Study concepts, example questions & explanations for High School Biology
All High School Biology Resources
Example Questions
Example Question #1 : Excretory System
Which section of the nephron is responsible for concentrating the solute in the filtrate?
Glomerulus
Distal convoluted tubule
Proximal convoluted tubule
Loop of Henle
Loop of Henle
The nephron is composed of multiple sections, which are used to control filtrate solute concentration and form urine. The proximal convoluted tubule does not alter solute concentration, and the distal convoluted tubule decreases solute concentration in the filtrate. It is the loop of Henle that increases the solute concentration of the filtrate.
Example Question #1 : Understanding Nephron Function
Filtration occurs in what section of the nephron?
Glomerulus
Distal convoluted tubule
Loop of Henle
Proximal convoluted tubule
Glomerulus
Filtration occurs in the renal corpuscle, which is composed of the glomerulus and Bowman's capsule. The glomerulus filters the blood, resulting in the filtrate, which will then go through the tubules. The proximal and distal convoluted tubules are primarily involved in solute reabsorption, and the loop of Henle helps concentrate the urine.
Example Question #2 : Understanding Nephron Function
Which molecules are filtered through the glomerulus into Bowman’s capsule?
Water and nitrogenous compounds
Red blood cells and blood proteins
Small ions, glucose, amino acids
Two of these are correct
Two of these are correct
Water, small molecules, and ions are forced through the glomerular capillaries into Bowman’s capsule in the process of filtration, largely due to the high blood pressure in the capillaries of the glomerulus. Nitrogenous compounds, namely urea, are filtered into Bowman's capsule for excretion. Glucose is also filtered into the capsule, but is reabsorbed in the proximal convoluted tubule; the presence of glucose in the final filtrate or urine can be indicative of diabetes or other maladies.
The correct answer is that two answer options are correct: small ions, glucose, amino acids, water, and nitrogenous compounds are all found in the initial filtrate.
Large molecules and cells are never filtered through the podocytes (cells lining the capsule), so we never expect to find blood cells or large blood proteins like albumin in the filtrate.
Example Question #3 : Understanding Nephron Function
Which of the following is considered the functional cell of the kidney and works to filter fluids passing through the kidney?
Hilum
Papillary ducts
Cortices
Calyces
Nephron
Nephron
The nephrons are the basic filtration units of the kidneys. In the cortex (plural "cortices") or outer portion of the kidney, blood enters a nephron consisting of a glomerulus (mass of capillaries), renal tubules and loop of Henle. Urine is formed by filtration in the glomerulus and reabsorption and secretion in the tubules. The inner medulla of the kidney contains the collecting ducts, which merge together to form papillary ducts that enter into a calyx (plural "calyces") or funnel-shaped structure. The hilum is the part where the renal artery enters and renal vein and ureter leave the kidney.
Example Question #4 : Understanding Nephron Function
What is the molecule that determines whether urine will be concentrated or dilute by controlling the amount of water reabsorbed from the nephron into the bloodstream?
Follicle-stimulating hormone
Antidiuretic hormone (vasopressin)
Glucose
Prostaglandins
Epinephrine
Antidiuretic hormone (vasopressin)
The correct answer is antidiuretic hormone (ADH), also known as vasopressin. ADH controls the permeability of the collecting duct of the nephron to water. If ADH levels are high in the blood, more water will be reabsorbed into the bloodstream, concentrating the urine. Alternatively, if ADH levels are low, less water is reabsorbed into the bloodstream, and the urine is dilute.
All High School Biology Resources
