Propantheline can be used for the treatment of peptic ulcer disease because it decreases gastric acid secretion. What prototype drug is most like propantheline?

Correct Answer: A

Rationale: Rationale: Atropine is the correct answer as it is an anticholinergic agent like propantheline, both inhibiting acetylcholine activity. This action reduces gastric acid secretion, aiding in peptic ulcer treatment. Neostigmine (B) increases acetylcholine activity, opposite to propantheline's effect. Propranolol (C) is a beta-blocker, not directly affecting gastric acid secretion. Phentolamine (D) is an alpha-blocker, also not related to reducing gastric acid secretion.

Correct Answer: B

Rationale: The correct answer is B: neutralisation, yellow. In a neutralization reaction between an acid and a base, the acidic and basic properties neutralize each other, resulting in a salt and water. The indicator phenolphthalein is commonly used in acid-base titrations, turning pink in basic solutions and colorless in acidic solutions. When the reaction is complete and the solution is neutral (pH 7), phenolphthalein appears yellow. Therefore, the color of the mixture at the end of a neutralization reaction is yellow. Choices A, C, and D are incorrect because neutralization reactions typically result in a yellow color, not orange, and redox reactions do not involve the same color changes as neutralization reactions.

Correct Answer: D

Rationale: The correct answer is D. In circuit symbols, a heater is typically represented by a zigzag line enclosed in a rectangle. This symbol signifies the generation of heat through resistance. Option A does not resemble a heater symbol, Option B is a resistor symbol, and Option C is a light bulb symbol. Therefore, the correct answer is D as it accurately represents a heater in circuit diagrams.

Correct Answer: B

Rationale: The correct answer is B: paracrine. Paracrine signaling involves the release of signaling molecules into the extracellular fluid to affect nearby target cells. This type of signaling is localized and affects cells within close proximity. Autocrine signaling (A) involves cells releasing signals that act on themselves, endocrine signaling (C) involves signaling molecules being released into the bloodstream to affect distant target cells, and neural signaling (D) involves the transmission of signals through neurons. In this case, paracrine signaling specifically targets local cells by releasing chemicals into the extracellular fluid, making it the correct choice.

Correct Answer: C

Rationale: Step 1: The congenital condition described points towards a disorder affecting growth and development. Step 2: The symptoms of mental retardation, short body size, and thick neck suggest hypothyroidism. Step 3: Thyroxin is a hormone produced by the thyroid gland that regulates metabolism and growth. Step 4: A deficiency of thyroxin in congenital hypothyroidism leads to the described symptoms. Step 5: Therefore, the correct answer is C: deficiency of thyroxin. Summary: A: Insulin deficiency does not match the symptoms described. B: Thymosin deficiency is not related to growth and mental retardation. D: Excess of synthetic growth hormone would not cause mental retardation and thick neck.