Review notes · 96 high-yield checks
MDCAT rapid review.
Use these as a last-pass correction sheet: try the prompt, open the answer, then retain the one line that prevents the usual mistake.
Physics
Motion, waves & electricity
1. At what angle is a projectile's range maximum?
Answer: 45°
Recall: R = u²sin 2θ / g; sin 2θ is maximum at 2θ = 90°.
2. At what angle is maximum height greatest?
Answer: 90°
Recall: H = u²sin²θ / 2g; it rises with sin²θ.
3. The range is one-sixth of maximum at which angles?
Answer: About 4.8° and 85.2°
Recall: sin 2θ = 1/6; complementary angles give the same range.
4. Distance between a node and its nearest antinode?
Answer: λ/4
Recall: Adjacent nodes are λ/2 apart.
5. Phase difference between displacement and acceleration in SHM?
Answer: π rad
Recall: a = −ω²x: acceleration is opposite to displacement.
6. Where are kinetic and potential energies equal in SHM?
Answer: At x = ±A/√2
Recall: Each is half the total energy.
7. In a full-wave rectifier fed by 50 Hz AC, output ripple frequency?
Answer: 100 Hz
Recall: Full-wave rectification doubles frequency.
8. Fleming's left-hand middle finger represents?
Answer: Current
Recall: First finger: field; thumb: force/motion; middle: current.
9. Fleming's right-hand middle finger represents?
Answer: Induced current
Recall: Right hand is for generator effect.
10. For a stationary source and observer moving towards it, observed frequency?
Answer: Increases
Recall: f′ = f(v + vo)/v.
11. Usual SI unit of intensity?
Answer: W m⁻²
Recall: Power per unit area.
12. A source of water waves travels fastest in which water?
Answer: Deep water
Recall: Wave speed increases with depth in shallow-water behaviour.
Chemistry
Organic, polymers & equilibrium
1. Fischer esterification is which reaction type?
Answer: Condensation
Recall: Carboxylic acid + alcohol → ester + water.
2. Terminal alkynes are acidic because the terminal carbon is?
Answer: sp hybridized
Recall: Greater s-character stabilises the conjugate base.
3. PVC is classified as?
Answer: Thermoplastic homopolymer
Recall: It is made from repeating vinyl chloride monomer.
4. Polymer made by condensing epichlorohydrin and bisphenol A?
Answer: Epoxy resin
Recall: A common thermosetting resin.
5. Sulfonamides are which enzyme inhibitors?
Answer: Competitive inhibitors
Recall: They compete with PABA in folate synthesis.
6. A basic buffer contains which pair?
Answer: Weak base + its salt, e.g. NH₄OH and NH₄Cl
Recall: Added H⁺ is taken up by the weak base.
7. On adding H⁺ to NH₄OH/NH₄Cl buffer, equilibrium shifts?
Answer: Forward
Recall: NH₄OH + H⁺ → NH₄⁺ + H₂O.
8. General requirement for free-radical halogenation of an alkane?
Answer: Heat or UV light
Recall: Initiation forms halogen radicals.
9. Which is NOT a characteristic of benzene?
Answer: High reactivity
Recall: Aromatic resonance makes benzene unusually stable.
10. Ksp of PbSO₄ is 1.6 × 10⁻⁸. Its solubility in pure water?
Answer: 1.26 × 10⁻⁴ mol L⁻¹
Recall: For 1:1 salt, Ksp = s².
11. BiCl₃ + H₂O ⇌ BiOCl + 2HCl: milkiness increases on adding?
Answer: Water / dilution
Recall: Dilution shifts hydrolysis to the right.
12. Which variable is kept constant in the usual gas laws?
Answer: Number of moles
Recall: Boyle, Charles and Gay-Lussac compare a fixed sample of gas.
Biology
Human physiology, reproduction & immunity
1. B lymphocytes mature in?
Answer: Bone marrow
Recall: T lymphocytes mature in thymus.
2. MHC class I presents antigen to?
Answer: CD8 cytotoxic T cells
Recall: MHC II presents to CD4 helper T cells.
3. How many antigen-binding sites does one antibody molecule have?
Answer: Two
Recall: The two Fab arms bind antigen.
4. Injection of snake-venom antibodies provides which immunity?
Answer: Artificial passive immunity
Recall: Ready-made antibodies; immediate but temporary protection.
5. Helicase separates DNA strands by breaking?
Answer: Hydrogen bonds between complementary bases
Recall: It does not break phosphodiester bonds.
6. Gaps between myelin sheath segments are called?
Answer: Nodes of Ranvier
Recall: They enable saltatory conduction.
7. Which urine-formation step is highly selective?
Answer: Selective reabsorption
Recall: Useful solutes are reclaimed according to body needs.
8. Amylase-deficient saliva is mainly secreted by?
Answer: Sublingual glands
Recall: Their secretion is predominantly mucous.
9. Fresh saliva pH in the Punjab textbook?
Answer: About 8
Recall: It becomes more acidic on standing as CO₂ changes.
10. Acrosome is formed by which organelle?
Answer: Golgi apparatus
Recall: It is a Golgi-derived cap containing hydrolytic enzymes.
11. Inhibin is produced by?
Answer: Sertoli cells
Recall: It inhibits FSH by negative feedback.
12. Hormone that suppresses spermatogenesis through feedback?
Answer: Inhibin
Recall: It specifically restrains FSH.
13. Layers around mammalian egg, outside to inside?
Answer: Corona radiata → zona pellucida → plasma membrane
Recall: Remember corona outside, membrane inside.
14. Most thickness of uterine wall is due to?
Answer: Myometrium
Recall: The muscular middle layer is the thickest.
15. SCID results from absence of which enzyme in standard MDCAT context?
Answer: Adenosine deaminase (ADA)
Recall: Loss impairs lymphocyte development.
16. First successful vaccine was against?
Answer: Smallpox
Recall: Jenner used cowpox material.
Biology
Cells, biomolecules & nervous system
1. Most abundant biomolecule in a cell?
Answer: Water
Recall: It is the main cellular constituent by mass.
2. Glycogen contains which glycosidic links?
Answer: α-1,4 in chains and α-1,6 at branches
Recall: Branches use α-1,6 bonds.
3. α-helix and β-pleated sheet show which protein structure?
Answer: Secondary structure
Recall: Both are stabilised by hydrogen bonds.
4. Normal maximum speed of nerve impulse in myelinated fibres?
Answer: About 120 m s⁻¹
Recall: Myelin greatly speeds conduction.
5. Which neurons have a tree-like appearance?
Answer: Multipolar neurons
Recall: Many dendrites branch from the cell body.
6. Are interneurons typically multipolar?
Answer: Yes
Recall: They are common within the CNS.
7. Cold receptors are how many times more numerous than warm receptors?
Answer: About 10 times
Recall: A Punjab-textbook recall point.
8. Pain receptors are about how many times more numerous than cold receptors?
Answer: About 27 times
Recall: Use this with the 10× cold:warm fact.
9. Which collagen type predominates in cartilage?
Answer: Type II collagen
Recall: Bone chiefly contains type I collagen.
10. Dentin is best described as?
Answer: Calcified tissue beneath enamel/cementum
Recall: It forms most of the tooth.
11. Joint between head of humerus and pectoral girdle?
Answer: Ball-and-socket joint
Recall: The glenohumeral joint allows wide movement.
12. Joint at costal cartilage and sternum is commonly classified as?
Answer: Slightly movable / cartilaginous
Recall: It permits small respiratory movements.
Physics
Electromagnetism, thermal physics & modern physics
1. EMF is written as E = V + Ir when?
Answer: When a cell is supplying current
Recall: Terminal potential V = E − Ir, so E = V + Ir.
2. EMF is written as E = V − Ir when?
Answer: When a cell is being charged
Recall: Current enters the positive terminal, making V = E + Ir.
3. Force on a straight current-carrying conductor?
Answer: F = BIL sin θ
Recall: Use conductor length in the field—not its cross-sectional area.
4. Compton shift is maximum at which scattering angle?
Answer: 180°
Recall: Δλ = h(1 − cos θ)/mc; backscatter gives the maximum.
5. Heat of vaporisation of water in kcal kg⁻¹?
Answer: About 540 kcal kg⁻¹
Recall: This is the latent heat at 100°C.
6. What is the pressure/temperature condition often used for Haber process in MDCAT questions?
Answer: About 450°C and 200 atm
Recall: Do not confuse it with extreme-pressure industrial processes.
7. In a conductor at 90° to B, magnetic force direction follows?
Answer: Fleming's left-hand rule
Recall: Motor effect: field, current, force.
8. In sound, loudness response of the ear is approximately?
Answer: Logarithmic
Recall: Equal ratios of intensity feel like roughly equal loudness changes.
9. For a pendulum, the phase relation of velocity and acceleration is?
Answer: π/2 rad
Recall: Velocity is quarter-cycle out of phase with displacement; acceleration opposes displacement.
10. What quantity is zero at the mean position in SHM?
Answer: Potential energy (relative to mean position)
Recall: Speed and kinetic energy are maximum there.
11. Normal reflection/refraction questions: refractive index is?
Answer: c/v
Recall: Light slows in a medium, so n rises as speed falls.
12. What is the frequency of an AC supply labelled 220 V, 50 Hz?
Answer: 50 Hz
Recall: The instantaneous current may be I₀sin 2πft.
Chemistry
Reactions, redox & biomolecules
1. Tollens' reagent gives a positive test with?
Answer: Aldehydes
Recall: It is reduced to a silver mirror while the aldehyde is oxidised.
2. Iodoform test is characteristic of?
Answer: CH₃CO− group or CH₃CH(OH)− group
Recall: Methyl ketones and ethanol/secondary methyl alcohols qualify.
3. Cannizzaro reaction occurs with aldehydes that lack?
Answer: α-hydrogen
Recall: One aldehyde is oxidised and another reduced.
4. In esterification, the −OH of the acid is replaced by?
Answer: −OR from the alcohol
Recall: The ester has RCOOR′ structure.
5. Which hydrogen halide adds most readily to alkenes?
Answer: HI
Recall: Reactivity: HI > HBr > HCl > HF.
6. Ease of reduction among Ag⁺ and Cu²⁺?
Answer: Ag⁺ is reduced more easily
Recall: Ag⁺/Ag has the higher standard reduction potential.
7. Which has higher vapour pressure at room temperature: acetone or benzene?
Answer: Acetone
Recall: Its lower boiling point means weaker overall intermolecular attraction.
8. Phosphoglyceromutase belongs to which enzyme class?
Answer: Transferases
Recall: Mutases transfer a functional group within the same molecule.
9. Succinyl-CoA synthetase (succinic thiokinase) is which class?
Answer: Ligase
Recall: It catalyses ATP/GTP-linked bond formation in the TCA cycle.
10. Lyases generally catalyse?
Answer: Addition/removal of groups without hydrolysis or oxidation
Recall: They often create or remove double bonds.
11. A common-ion effect generally changes solubility how?
Answer: Decreases it
Recall: Added common ion shifts dissolution equilibrium left.
12. What is a buffer's key role?
Answer: Resists change in pH
Recall: It removes small added amounts of H⁺ or OH⁻.
Biology
Digestion, circulation & pathogens
1. After a fatty meal, fat globules may form about what proportion of lymph?
Answer: About 1%
Recall: Lacteals absorb dietary fat into lymph as chyle.
2. Main function of lymph regarding fats?
Answer: Transports absorbed lipids from intestinal lacteals to blood
Recall: It also returns tissue fluid and supports immunity.
3. Hepatitis D is linked with which type of agent?
Answer: Defective RNA agent requiring hepatitis B virus
Recall: It depends on HBV surface antigen for packaging.
4. Pig is an important source of which hepatitis infection?
Answer: Hepatitis E
Recall: HEV can be zoonotically transmitted.
5. HIV contains which nucleic acid?
Answer: Single-stranded RNA
Recall: It is a retrovirus and carries reverse transcriptase.
6. Influenza virus has which nucleic acid?
Answer: Single-stranded RNA
Recall: It is an RNA virus with a segmented genome.
7. Pox virus is unusual because it contains?
Answer: Double-stranded DNA
Recall: It replicates in cytoplasm despite being a DNA virus.
8. Polio virus contains?
Answer: Single-stranded RNA
Recall: A positive-sense RNA enterovirus.
9. Virus first discovered historically?
Answer: Tobacco mosaic virus
Recall: Ivanovsky and Beijerinck established the filterable-agent concept.
10. Sweating is controlled mainly by which autonomic division?
Answer: Sympathetic nervous system
Recall: Eccrine sweat glands are sympathetically innervated.
11. What do osteoblasts become after being trapped in matrix?
Answer: Osteocytes
Recall: Osteocytes maintain bone tissue.
12. Osteoclast function?
Answer: Bone resorption
Recall: They are multinucleated cells that break down bone.
English
Grammar & meaning traps
1. In 'The captain stood at the head of the table,' head means?
Answer: Front/end part of the table
Recall: It describes position, not the captain's authority.
2. Subject–verb agreement: 'Each of the students ___ ready.'
Answer: is
Recall: Each is singular even when followed by of + plural noun.
3. Subject–verb agreement: 'Neither Ali nor his friends ___ coming.'
Answer: are
Recall: With neither/nor, the verb agrees with the nearer subject.
4. Subject–verb agreement: 'The number of students ___ increasing.'
Answer: is
Recall: The number is singular; 'a number of' takes plural.
5. A word referring to a body part can be figurative in a sentence. What resolves its meaning?
Answer: Context
Recall: Choose the sense that fits the whole phrase, not the most familiar sense.
6. In a sentence, 'authority' normally means?
Answer: Power or right to command
Recall: It is distinct from a spatial word such as head/front.
7. In a sentence, 'senior' normally means?
Answer: Higher in rank or older in service
Recall: It is distinct from physical position at a table.
8. Best strategy for an English MDCAT MCQ when two options look plausible?
Answer: Eliminate by grammar and exact context
Recall: Do not choose a broadly related meaning over the precise one.