The presence of which substance in the urine is an indirect evidence of a urinary tract infection because Gram-negative bacteria metabolize nitrates into it?
Explanation
This question assesses the ability to interpret urinalysis findings, specifically the significance of nitrites as an indicator of a bacterial infection.
Other questions
What is the term for the virtual absence of urine production, defined as an output below 50 mL/day?
Which yellow pigment, a breakdown product of red blood cell destruction, is primarily responsible for the color of normal urine?
The kidneys must produce a minimum urine volume of about how many milliliters per day to adequately rid the body of wastes?
What is the name of the triangular-shaped area at the base of the bladder, formed by the two ureteral openings and the urethral opening?
The micturition reflex is initiated when stretch receptors in the bladder wall are stimulated, which typically occurs when bladder volume reaches about how many milliliters?
Which structure allows urine to enter the bladder but prevents reflux of urine back into the ureter, functioning as a physiological sphincter?
What are the connective tissue extensions that radiate downward from the renal cortex to separate the renal pyramids called?
What percentage of nephrons are juxtamedullary nephrons, which have long loops of Henle extending deep into the medulla?
The filtration membrane of the renal corpuscle permits the rapid movement of filtrate through pores that are only about how many nanometers in diameter?
What cluster of cuboidal epithelial cells in the distal convoluted tubule monitors the fluid composition and signals the juxtaglomerular cells?
What is the average glomerular filtration rate (GFR) for women, representing the volume of filtrate formed by both kidneys per minute?
What is the calculated Net Filtration Pressure (NFP) if the glomerular blood hydrostatic pressure (GBHP) is 55 mm Hg, the capsular hydrostatic pressure (CHP) is 15 mm Hg, and the blood colloid osmotic pressure (BCOP) is 30 mm Hg?
The tubuloglomerular feedback mechanism involves the JGA and paracrine signaling. When GFR increases, what do the macula densa cells release to cause vasoconstriction of the afferent arteriole?
Which hormone, often called the 'salt-retaining hormone,' is released from the adrenal cortex and promotes Na+ reabsorption by the nephron?
What percentage of circulating erythropoietin (EPO), the hormone that stimulates red blood cell production, is produced in the kidneys?
What is the name of the voluntary skeletal muscle that must be consciously relaxed to allow urination?
The kidney is a portal system where a capillary bed (the glomerulus) drains into a vessel that in turn forms a second capillary bed. What type of vessel is found between the first and second capillary beds?
Active renin cleaves several amino acids from angiotensinogen to produce angiotensin I. How many amino acids is active renin comprised of?
What percentage of the filtrate is normally reabsorbed back into the circulation, resulting in only 1–2 liters of urine being produced per day?
In the Proximal Convoluted Tubule (PCT), almost 100 percent of glucose is recovered. What is the maximum amount of glucose that can be recovered per minute in men before it starts appearing in the urine?
The countercurrent multiplier system creates a hyperosmotic environment in the kidney medulla. As the forming urine moves through the descending loop of Henle, its osmolarity increases from about 300 mOsmol/kg to about what value?
What hormone induces the insertion of calcium channels on the luminal surface of DCT cells to enhance calcium recovery from the forming urine?
Which cells in the collecting ducts play significant roles in regulating blood pH by reabsorbing K+ and HCO3– while secreting H+?
The kidneys are very effective at autoregulating blood flow. When blood pressure increases, the smooth muscle cells in the wall of the afferent arteriole are stretched and respond by contracting. What is this mechanism called?
Atrial natriuretic hormone (ANH) is a 28-amino acid peptide produced by the heart atria in response to what stimulus?
Which compound that increases urine volume works by inhibiting the release of ADH from the posterior pituitary?
The regulation of which ion is closely mirrored by the regulation of sodium, as it is the dominant anion in the extracellular fluid?
The kidneys play a crucial role in activating Vitamin D. Specifically, they add an -OH group to calcidiol to make what active form of vitamin D?
What is the normal pH range of urine, which can be influenced by diet?
What is the average length of the male urethra?
The afferent arterioles of the kidney service approximately how many nephrons in each kidney?
What enzyme, located in the lungs, is functionally important for converting inactive angiotensin I into active angiotensin II?
What are the two distinct cell types found in the collecting ducts that possess channels for recovery of sodium, potassium, acid, or bicarbonate?
Nitrogen wastes are produced by the breakdown of proteins. Which nitrogenous waste product is most of the highly toxic ammonia rapidly converted into in the liver?
The heart pumps about 5 L of blood per minute, and approximately what percentage of this cardiac output enters the kidneys to be filtered under resting conditions?
Systemic blood pressure must stay above what approximate level to ensure that the mean arterial pressure is adequate to maintain glomerular filtration?
Which part of the nephron is most metabolically active and responsible for reabsorbing about 67 percent of water and sodium, and almost 100 percent of glucose and amino acids?
Which portion of the Loop of Henle is completely impermeable to water due to the absence of aquaporin proteins?
Systemic edema, or the 'plumping up' of tissues and cells, can result from a deficiency of circulating plasma proteins, primarily which protein?
What is the collective name for the tuft of capillaries and the surrounding Bowman's capsule?
The normal osmolarity of urine can range from a low of 50-100 mOsmol/L to as high as what value?
Which part of the male urethra passes through the prostate gland and receives sperm via the ejaculatory ducts?
The kidneys are well protected by muscle, fat, and ribs and lie in the retroperitoneal space between the parietal peritoneum and the posterior abdominal wall. The left kidney is located at about which vertebral levels?
What are the finger-like arms of podocytes that interdigitate to form filtration slits?
What is the term for the movement of water across the PCT membrane that is 'obliged' to follow the active transport of Na+?
What is the primary function of the enzyme carbonic anhydrase (CA) in the cells of the PCT?
Angiotensin II is a systemic vasoconstrictor that helps regulate blood pressure. It also stimulates the release of which steroid hormone from the adrenal cortex?
What term describes the condition where glucose appears in the urine, usually because blood glucose levels exceed the transport capacity of the kidneys?
What is the name of the capillary network that surrounds the more distal portions of the nephron tubule and recovers most of the solutes and water?