Entrance Exams
Govt. Exams
During isovolumetric contraction, ventricular volume stays constant while pressure rapidly increases as both AV and semilunar valves are closed.
The cerebellum compares intended movements with actual movements, providing real-time corrections for coordination, balance, and fine motor control.
Type 2 diabetes involves insulin resistance where cells don't respond properly to insulin, maintaining elevated blood glucose despite insulin presence.
Thrombin is a serine protease that cleaves fibrinogen into fibrin monomers, which polymerize to form the structural basis of blood clots.
The parasympathetic nervous system (via vagus nerve) releases acetylcholine, which decreases heart rate and force of contraction through M2 receptors.
Myasthenia gravis is an autoimmune disorder where antibodies attack acetylcholine receptors at the neuromuscular junction, reducing muscle contraction capability.
Renin, secreted by juxtaglomerular cells, cleaves angiotensinogen to form angiotensin I, which is then converted to angiotensin II by ACE.
During absolute refractory period, inactivated sodium channels cannot open regardless of stimulus strength, making another action potential impossible.
Low oxygen at high altitude stimulates EPO release, which increases RBC production, restoring oxygen levels and decreasing EPO secretion—a classic negative feedback loop.
Both PTH and calcitonin regulate calcium-phosphate balance. PTH increases blood calcium while calcitonin decreases it through opposing mechanisms.