During which stage of mitosis do spindle fibers attach to the centromeres of chromosomes? MCQ with Answer and Explanation

Explanation:
The vocal cords (folds) in the larynx vibrate as air passes, producing sound. Pitch is controlled by tension. Epiglottis prevents food entry, trachea is airway.

Explanation:
All three are correct: SA node initiates impulse, AV node delays it to allow atrial emptying, Purkinje fibers spread impulse through ventricles.

Explanation:
Lipase is the fat-digesting enzyme, produced mainly by the pancreas (pancreatic lipase) and also by lingual and gastric glands. It hydrolyzes triglycerides into monoglycerides and free fatty acids. Bile salts emulsify fats, increasing surface area for lipase action. Amylase digests starch, pepsin digests proteins, sucrase hydrolyzes sucrose. Lipase requires colipase for optimal activity.