During which stage of mitosis does the nuclear envelope begin to disappear and the chromosomes start attaching to the spindle forming along the cell's axis?

Correct Answer: A

Rationale: The correct answer is A, Prometaphase. During prometaphase, the nuclear envelope disintegrates, and chromosomes start attaching to spindle fibers. In metaphase, chromosomes align in the middle of the cell. Anaphase is characterized by the separation of sister chromatids, and prophase involves the condensation of chromosomes and the beginning of spindle formation.

Correct Answer: A

Rationale: Proteins are indeed polymers made up of amino acids. Amino acids are the building blocks of proteins, where each protein has a unique sequence of amino acids that determines its structure and function. Phospholipids, carbohydrates, and fatty acids are not molecules that make up proteins. Phospholipids are the main components of cell membranes, carbohydrates are sugars used for energy and structural purposes, and fatty acids are building blocks of lipids.

Correct Answer: A

Rationale: Taxonomy is the science of naming, defining, and classifying groups of biological organisms based on shared characteristics. Physiology (choice B) is the study of the functions and processes of living organisms, not classification. Botany (choice C) is the study of plants, while Zoology (choice D) is the study of animals. Therefore, the correct answer is Taxonomy (choice A).

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 A: Deoxyribonucleic acid (DNA). DNA contains the genetic information essential for replication, ensuring the accurate transmission of genetic material from one generation to the next. Choice B, Transfer RNA (tRNA), is involved in protein synthesis, not replication. Choice C, Messenger RNA (mRNA), carries genetic information from DNA to the ribosome but does not contain the code for replication. Choice D, Ribonucleic acid (RNA), is a broader category that includes both mRNA and tRNA, but the specific molecule containing the code required for replication is DNA.