Deficiency of which vitamin causes night blindness? MCQ with Answer and Explanation

Explanation:
Ribosomes are the only organelles common to both prokaryotes and eukaryotes, though sizes differ: 70S in prokaryotes, 80S in eukaryotes. Nuclear membrane, mitochondria, and Golgi are absent in prokaryotes. Ribosomes are the site of protein synthesis. This commonality supports the universal role of protein synthesis in all life forms. Mycoplasma, the smallest prokaryote, also has ribosomes.

Explanation:
The plasma membrane (cell membrane) is selectively permeable, regulating the entry and exit of substances into and out of the cell, maintaining internal homeostasis. The nucleus is the membrane-bound organelle that houses the cell's genetic material (DNA) organized into chromosomes, directing cellular activities. Mitochondria are the double-membrane-bound organelles known as the 'powerhouses of the cell' because they are the primary site of aerobic respiration, producing the majority of the cell's ATP (energy currency). All statements are correct.

Explanation:
The cerebrum is the largest part of the brain, responsible for higher functions like voluntary motor actions, sensory processing, and intelligence. The cerebellum coordinates muscle movements and maintains posture and balance. The medulla oblongata contains vital centers controlling involuntary functions like heartbeat, breathing, and blood pressure. All three statements are correct.