Pathway of Antibody Synthesis and Secretion

Steps:

• Nucleus transcribes DNA to mRNA for antibody protein.
• Ribosome translates mRNA into the antibody polypeptide chain.
• Golgi body modifies and packages the antibody for secretion.
• Vesicle transports the processed antibody out of the cell.

Why B is correct:

• Antibodies are proteins synthesized via transcription in the nucleus, translation at ribosomes, modification in the Golgi, and vesicular transport, matching the listed sequence per cellular biology.

Why the others are wrong:

• A: Lipid synthesis occurs mainly in the endoplasmic reticulum and mitochondria, bypassing nucleus-ribosome-Golgi-vesicle order.
• C: Sizes vary (ribosome smallest, then vesicle; nucleus and Golgi larger), so order does not increase.
• D: Order does not decrease in size (nucleus largest, ribosome smallest).

Final answer: B