Free OAT Exam Questions That Helps Candidates Pass

Comprehensive and Detailed Explanation (150–250 words):

Phospholipids form bilayers with hydrophilic heads and hydrophobic tails. Proteins (A) and carbohydrates (D) are important but secondary. Steroids (C), like cholesterol, modulate fluidity. Main component = B.

Comprehensive and Detailed Explanation (150–250 words):

The passage praises growth of renewables but states obstacles: storage technology and grid integration. Options A, C, and D are not mentioned. Correct: B.

Comprehensive and Detailed Explanation (150–250 words):

Base-pairing: A–U, T–A, C–G, G–C. DNA 5′–ATCG–3′ → RNA 3′–UAGC–5′. Correct: D.

Comprehensive and Detailed Explanation (150–250 words):

Prolactin, secreted by the anterior pituitary, stimulates mammary glands to produce milk. Oxytocin (A) triggers milk ejection (“let-down reflex”) but not production. Estrogen and progesterone (C and D) regulate breast development but do not directly produce milk. Thus, the correct answer is B (Prolactin).

Comprehensive and Detailed Explanation (150–250 words):

Hemoglobin binds oxygen via iron in heme groups, transporting it through the bloodstream. Myoglobin (A) stores oxygen in muscle tissue. Actin (C) and keratin (D) are structural proteins. Correct: B.