The diagram below represents a process that occurs in organisms. A Broken down to B. Which row in the chart indicates what A and B in the boxes could represent?

Correct Answer: C

Rationale: Step 1: A broken down to B represents the breakdown of proteins into amino acids. Step 2: Proteins are made up of amino acids. Step 3: Therefore, A represents proteins and B represents amino acids. Summary: Choice A is incorrect as starch does not break down into proteins. Choice B is incorrect as starch breaks down into simple sugars, not amino acids. Choice D is incorrect as proteins do not break down into simple sugars.

Correct Answer: A

Rationale: The correct answer is A because the function of structure X's secretions is to increase the surface area of fats for better digestion and absorption in the small intestine. This is achieved by emulsifying fats into smaller droplets, aiding in their breakdown by lipase enzymes. Choices B, C, and D are incorrect as structure X is not involved in stomach acid secretion to decrease pH, protein digestion to peptides, or glycogen breakdown to maltose. The primary role of structure X is related to fat digestion, making choice A the most suitable option.

Correct Answer: A

Rationale: The correct answer is A: basic. Trypsin is a protease enzyme that functions best in basic conditions, specifically at a pH around 8. This is because its active site contains amino acid residues that are positively charged at basic pH, facilitating substrate binding and catalysis. In acidic conditions (choice B), the active site residues may become protonated and lose their positive charge, leading to decreased enzyme activity. Neutral conditions (choice C) are suboptimal for trypsin as it requires basic pH for optimal function. Low pH (choice D) is also not ideal for trypsin as it can denature the enzyme and hinder its catalytic activity.

Correct Answer: C

Rationale: The correct answer is C: liver. Glycogen is primarily stored in the liver and muscles. The liver serves as a major storage site for glycogen, acting as a reservoir for glucose when blood sugar levels drop. The pancreas (A) mainly produces digestive enzymes and hormones like insulin and glucagon. The small intestine (B) is involved in nutrient absorption, not glycogen storage. The large intestine (D) is mainly responsible for absorbing water and electrolytes, not storing glycogen. Therefore, C is the correct answer.

Correct Answer: D

Rationale: The correct answer is D: carbohydrates. Maltose is a disaccharide composed of two glucose molecules, which are carbohydrates. During digestion, carbohydrates such as starch are broken down into maltose by enzymes like amylase. Lipids (A), proteins (B), and nucleic acids (C) do not directly contribute to the formation of maltose in the digestive process. Therefore, the source of maltose during digestion is carbohydrates, making option D the correct choice.