The biodegradable plastic PHB (polyhydroxybutyrate) is produced by: MCQ with Answer and Explanation

Explanation:
Blood group O has neither A nor B antigens on the red blood cells, but has both anti-A and anti-B antibodies in plasma. It is the universal donor for red cells. Group AB has both antigens, A has A antigen, B has B antigen.

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:
Vernalization is the process by which many plants, particularly biennials and winter annuals (like winter wheat, cabbage, and carrots), require exposure to a prolonged period of low temperature (cold treatment) before they can initiate flowering. This prevents the plant from flowering in the autumn, ensuring it survives the winter and flowers in the spring or summer. The cold stimulus is perceived by the apical meristem or the germinating seed.