Most Repeated MDCAT MCQs by Subject: Biology, Chemistry, Physics & English
The core concepts that come back year after year in MDCAT, broken down by subject — with sample MCQs for Biology, Chemistry, Physics and English.
MDCAT doesn't test 11,000 random facts every year — it repeatedly tests the same load-bearing concepts from the FSc syllabus, because those are the concepts that actually distinguish a prepared candidate from an unprepared one. Knowing which concepts carry that weight, subject by subject, is worth more than blindly grinding an undifferentiated question bank.
This isn't a claim to have the exact wording of any specific past paper — treat it as a map of the concepts that show up in some form nearly every year, illustrated with sample questions in the same style you'll see in the real thing.
Biology — the highest-weight section
Biology carries the most marks on MDCAT, and the recurring themes are cell biology, genetics, human physiology (especially circulatory, digestive and nervous systems), and reproduction.
1. Which scientists first described the double-helix structure of DNA?
- A) Mendel and Darwin
- B) Watson and Crick ✅
- C) Pasteur and Koch
- D) Fleming and Florey
2. Which enzyme begins the breakdown of starch in the mouth?
- A) Pepsin
- B) Lipase
- C) Salivary amylase ✅
- D) Trypsin
3. The universal blood donor group is:
- A) AB positive
- B) O negative ✅
- C) A positive
- D) B negative
4. The normal diploid chromosome number in humans is:
- A) 44
- B) 48
- C) 46 ✅
- D) 23
Chemistry — recurring across physical, organic and inorganic
5. Avogadro's number is approximately:
- A) 6.022 × 10²³ ✅
- B) 3.14 × 10²³
- C) 9.8 × 10²³
- D) 1.6 × 10²³
6. The pH scale ranges from:
- A) 0 to 10
- B) 1 to 12
- C) 0 to 14 ✅
- D) 0 to 7
7. Which of the following is classified as a noble gas?
- A) Nitrogen
- B) Helium ✅
- C) Oxygen
- D) Chlorine
Physics — mechanics and electricity dominate
8. The SI unit of electric current is the:
- A) Volt
- B) Ohm
- C) Ampere ✅
- D) Watt
9. Newton's second law of motion states that force equals:
- A) mass ÷ acceleration
- B) mass × acceleration ✅
- C) mass × velocity
- D) mass ÷ velocity
10. The SI unit of frequency is the:
- A) Newton
- B) Hertz ✅
- C) Joule
- D) Tesla
English — smaller weight, easy to lock in
11. Choose the correctly punctuated sentence:
- A) "Its a good day."
- B) "It's a good day." ✅
- C) "Its' a good day."
- D) "It is' a good day."
12. Select the word that best completes: "The results were __________ inconclusive."
- A) large
- B) largely ✅
- C) larger
- D) largest
Why "Repeated Concepts" Beats "Memorised Answers"
Notice that every question above tests a concept, not a memorised fact string — MDCAT rewrites the surface wording every year, but the underlying idea (DNA structure, universal donor, Newton's second law) is stable. That's why chapter-wise, concept-first practice consistently outperforms cramming a single year's leaked paper.
HighYield's MDCAT question bank is organised the same way — by subject and topic, with a full explanation on every question so you're reinforcing the concept, not just memorising an answer key. The first 20 questions are free to try, no sign-in required, from the MDCAT question bank page.