Govt. Exams
Entrance Exams
Pulmonary surfactant (lipid + protein) reduces surface tension in alveoli, preventing their collapse during expiration and reducing work of breathing.
The kidneys produce approximately 90% of EPO, which stimulates red blood cell production in bone marrow when oxygen levels are low.
The loop of Henle creates a countercurrent multiplier system that establishes an osmotic gradient, enabling selective water reabsorption in the collecting duct.
Acetylcholine is the primary neurotransmitter at the neuromuscular junction, binding to nicotinic receptors on muscle fiber membranes to trigger muscle contraction.
Tidal volume, the volume of air inspired or expired during normal quiet breathing, is approximately 500 mL in adults.
The loop of Henle, particularly the descending and ascending limbs, creates a countercurrent multiplier system that establishes an osmotic gradient necessary for concentrated urine formation.
The SA node has the highest inherent rate of spontaneous depolarization (60-100 bpm), allowing it to set the rhythm for the entire heart.
Glucagon is secreted by alpha cells of pancreatic islets and increases blood glucose by promoting glycogenolysis and gluconeogenesis during fasting.
The glomerulus, a network of capillaries in the renal corpuscle, filters blood under hydrostatic pressure to produce the ultrafiltrate that forms the basis of urine.
Saltatory conduction occurs in myelinated neurons where action potentials jump between nodes of Ranvier, increasing conduction velocity significantly compared to unmyelinated fibers.
