Correct Answer: C

Rationale: The correct answer is C, 'Nucleus.' Prokaryotic cells do not have a defined nucleus, unlike eukaryotic cells. The plasma membrane, cytoplasm, and ribosomes are all components found in prokaryotic cells. The plasma membrane surrounds the cell and regulates what enters and exits, the cytoplasm is the gel-like substance that fills the cell, and ribosomes are responsible for protein synthesis.

Correct Answer: B

Rationale: The correct order of the stages of mitosis is Prophase, Prometaphase, Metaphase, Anaphase, and Telophase. Choice A is incorrect because it has Anaphase and Metaphase in the wrong order. Choice C is incorrect as it starts with Metaphase, which is not the first stage of mitosis. Choice D is incorrect as it also has the stages in the wrong order, and it starts with Metaphase, which is incorrect.

Correct Answer: A

Rationale: Glycolysis, the first step of cellular respiration, takes place in the cytosol and produces two molecules each of ATP, pyruvate, and NADH. Therefore, the correct answer is A. Choice B is incorrect as glycolysis produces two ATP molecules, not four. Choice C is incorrect as it incorrectly states that glycolysis produces four molecules of pyruvate and NADH. Choice D is incorrect because glycolysis produces two molecules of ATP, not four.

Correct Answer: A

Rationale: The correct answer is RNA. RNA, particularly mRNA, serves as the messenger that carries genetic information from DNA to the ribosome, where proteins are synthesized. Proteins (choice B) are not the genetic code's messenger; they are synthesized based on the information carried by RNA. DNA (choice C) stores the genetic information but does not directly act as the messenger. Carbohydrates (choice D) are not involved in transmitting genetic information.

Correct Answer: B

Rationale: The correct answer is B, Mitochondrion. Cellular respiration occurs in the mitochondria, where glucose is converted into energy through a series of metabolic processes. Choice A, Golgi apparatus, is incorrect as it is involved in modifying, sorting, and packaging proteins. Choice C, Chloroplast, is incorrect as it is the site of photosynthesis in plant cells, not cellular respiration. Choice D, Ribosome, is incorrect as it is responsible for protein synthesis, not energy production through cellular respiration.