Pakistan Army Medical Cadet Route cheat sheet

Number series: constant first difference = arithmetic progression; constant ratio between terms = geometric; constant second difference = square or quadratic pattern.

Coding-decoding: convert letters to alphabet positions (A=1 ... Z=26) and test a fixed shift (+n / -n), reversal (A<->Z) or positional-square pattern before choosing.

Blood relations: draw a tree; grandfather's only son = father, mother's brother = maternal uncle, father's sister = paternal aunt, uncle's child = cousin.

Direction sense: fix North upwards; right turn = 90 degrees clockwise, left turn = 90 degrees anticlockwise; perpendicular legs of the final displacement are combined with Pythagoras.

Syllogism: a conclusion is valid only if it is true in every possible Venn diagram of the premises; 'all A are B' does not imply 'all B are A'.

Mirror image: a vertical mirror swaps left and right; a water image swaps top and bottom; A, H, I, M, O, T, U, V, W, X, Y are unchanged in a vertical mirror.

Alphabet position aids: EJOTY = 5, 10, 15, 20, 25; the reverse position of a letter equals 27 minus its forward position.

Odd-one-out: test every option against the same rule (category, parity, prime/composite, letter position) and reject the option that breaks the rule shared by the other three.

Organelle functions: mitochondria = ATP production; ribosomes = protein synthesis; lysosomes = intracellular digestion; chloroplasts = photosynthesis; nucleus = genetic control.

Photosynthesis: 6CO2 + 6H2O + light energy -> C6H12O6 + 6O2, catalysed by chlorophyll in chloroplasts.

Blood: O negative red cells are the universal donor and AB positive the universal recipient; Rh incompatibility matters in pregnancy.

DNA pairing: adenine-thymine (2 hydrogen bonds) and guanine-cytosine (3 hydrogen bonds); RNA replaces thymine with uracil.

Enzymes are protein catalysts that lower activation energy, are substrate-specific, and denature above roughly 40-50 degrees Celsius in the human body; pepsin works near pH 2, trypsin near pH 8.

Human heart: four chambers; the left side carries oxygenated blood, the aorta carries oxygenated blood, and the pulmonary artery is the only artery carrying deoxygenated blood.

Respiration yield: aerobic oxidation of one glucose molecule gives about 38 ATP; anaerobic respiration in muscle gives 2 ATP plus lactic acid.

Taxonomic hierarchy from broadest to narrowest: Kingdom, Phylum, Class, Order, Family, Genus, Species.

Hormones: insulin from pancreatic beta cells lowers blood glucose; glucagon from alpha cells raises it; thyroxine from the thyroid controls metabolic rate.

Atomic number Z = number of protons; mass number A = protons + neutrons; isotopes have equal Z but different A; ions differ in electron count only.

Mole: 1 mol = 6.022 x 10^23 particles; moles = mass / molar mass; 1 mol of any gas occupies 22.4 L at STP.

pH = -log[H+]; pH below 7 acidic, 7 neutral, above 7 basic; a change of one pH unit means a tenfold change in hydrogen-ion concentration.

Periodic trends: atomic radius decreases left to right across a period and increases down a group; electronegativity and ionisation energy increase left to right and up a group.

Balancing equations: the count of each element must be identical on both sides; only coefficients may be changed, never subscripts.

Reaction rules: acid + base -> salt + water; acid + reactive metal -> salt + hydrogen; acid + carbonate -> salt + water + carbon dioxide.

Common valencies: Group I metals = 1, Group II metals = 2, Group VII halogens = 1, oxygen = 2; metals lose electrons to form cations, non-metals gain electrons to form anions.

Redox: oxidation is loss of electrons and a rise in oxidation number; reduction is gain of electrons and a fall in oxidation number; the oxidising agent is itself reduced.

Kinematics (constant acceleration): v = u + at; s = ut + 0.5at^2; v^2 = u^2 + 2as.

Newton's laws: F = ma; weight W = mg with g = 9.8 m/s^2; action and reaction forces are equal and opposite but act on two different bodies, so they never cancel.

Energy: work = F s cos(theta); KE = 0.5mv^2; PE = mgh; in a closed system total mechanical energy is conserved.

Electricity: V = IR; series R = R1 + R2; parallel 1/R = 1/R1 + 1/R2; power P = VI = I^2R = V^2/R.

Optics: refractive index n = c/v = sin i / sin r; light travelling into a denser medium bends towards the normal; total internal reflection occurs only from denser to rarer medium beyond the critical angle.

Lens/mirror: 1/f = 1/v - 1/u for a lens and 1/f = 1/v + 1/u for a mirror with the real-is-positive convention; magnification m = v/u.

Fluids and solids: density = mass / volume; pressure = force / area; pressure at depth in a liquid P = rho g h.

SI units: force newton, energy joule, power watt, pressure pascal, frequency hertz, charge coulomb, resistance ohm.

Subject-verb agreement: a singular subject takes a singular verb even when a plural noun sits inside a following prepositional phrase ('The box of pens is heavy').

Tense rule: present perfect = has/have + past participle and links past to present; it cannot be used with finished time markers such as yesterday, last week, in 1998, where the simple past is required.

Passive formation: object becomes subject + correct tense of 'be' + past participle + optional 'by' agent.

Reported speech: shift the tense one step back, change pronouns to the speaker's viewpoint, and convert now->then, today->that day, tomorrow->the next day.

Articles: 'a' before consonant sounds and 'an' before vowel sounds, decided by pronunciation, hence 'an hour' but 'a university'.

Fixed prepositions: married to, depend on, afraid of, good at, congratulate on, listen to, prefer X to Y, insist on.

Comparison: one-syllable adjectives take -er/-est; three or more syllables take more/most; double comparatives ('more better') are always wrong.

Idioms: 'once in a blue moon' = very rarely; 'to burn the midnight oil' = to work late; 'a bolt from the blue' = a total surprise; 'to let the cat out of the bag' = to reveal a secret.

Vocabulary items: insert the option into a sentence before deciding, because a word can be correct in one sense and wrong in the required sense.

Percentage: x% of N = (x/100)N; percentage change = (new - old) / old x 100.

Speed, distance, time: speed = distance / time; 1 km/h = 5/18 m/s; relative speed is the sum for opposite directions and the difference for the same direction.

Average = sum of values / number of values; adding a constant k to every value raises the average by exactly k.

Mensuration: circle area pi r^2, triangle 0.5 x base x height, trapezium 0.5(a+b)h; cylinder volume pi r^2 h; sphere volume (4/3)pi r^3; cone volume (1/3)pi r^2 h.

Quadratic ax^2 + bx + c = 0: x = [-b +/- sqrt(b^2 - 4ac)] / 2a; sum of roots = -b/a; product of roots = c/a; discriminant b^2 - 4ac decides the nature of roots.

Ratio and work: if a:b = 2:3 write a = 2k, b = 3k; one person finishing a job in n days does 1/n of the work per day.

Interest: simple interest = PRT/100; compound amount = P(1 + R/100)^T.

Pythagoras: a^2 + b^2 = c^2; standard triples 3-4-5, 5-12-13, 8-15-17, 7-24-25.

Standard angles: sin 30 = 1/2, cos 30 = sqrt3/2, tan 45 = 1, sin 60 = sqrt3/2, cos 60 = 1/2.

Big Five model (OCEAN): Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism; each trait is a continuum, not a pass/fail category.

Forced-choice items compare two equally desirable statements; there is no answer key, and the profile is built from the pattern of choices across many items.

Consistency check: similar items are repeated in different wording; contradictory answers between them lower the validity of the profile and are flagged.

Fight-or-flight response: sympathetic activation releases adrenaline, raising heart rate, breathing rate and blood glucose and diverting blood to skeletal muscle.

Yerkes-Dodson law: performance rises with arousal up to a moderate optimum and then declines when arousal becomes too high or too low.

Rating dimensions used in assessment centres typically include leadership, initiative, social adjustment, emotional stability, decisiveness and cooperation.

Response bias forms: social-desirability bias (choosing the 'ideal' answer), central-tendency bias (choosing only middle options) and extreme responding are all detectable patterns.

Psychometric instruments are scored for reliability and internal consistency, so random or rushed answering produces a flatter, less interpretable profile.

Panel structure typically runs: self-introduction, academic and family background, current affairs and defence awareness, situational questions, then the candidate's own questions.

Consistency rule: every stated fact about age, education, family and motivation is cross-checked against documents and earlier written/psychological records; a repeated question tests consistency, not memory.

STAR rule for experience questions: state the Situation, the Task, the Action you personally took, and the Result.

Situational rule: state the governing principle first (discipline, honesty, team safety), then the action, then the expected outcome.

Defence awareness baseline: Pakistan's three services are the Army, Navy and Air Force; the Chief of Army Staff holds four-star rank; Defence Day is 6 September.

Admission of not knowing is acceptable when followed by a reasoned approach; inventing an unverifiable fact is scored as a credibility failure.

Indicative officer-cadet sequence: initial written tests, physical test, initial medical, ISSB assessment, final medical board, then merit list and commission.

Communication scoring covers clarity, brevity, confident posture, audible voice and answer relevance; long, drifting answers are rated lower than direct ones.

Assessment dimensions in group discussion: relevance of content, clarity, listening, building on others' points, cooperation and contribution to a group conclusion; volume of speech is not scored.

Entry rule: contribute within the first few minutes with two or three substantive points, then support or refine others' points rather than repeating them.

Leaderless group task: no leader is appointed, so the group must self-organise, plan, allocate roles and finish within the time limit.

Common task families: group planning (map or route problem), progressive group task, half group task, command task and construction/obstacle tasks.

Blocking behaviour (interrupting, monopolising, ridiculing) is scored more negatively than quiet but cooperative participation.

Disagreement rule: challenge the idea with a reason, never the person, and accept the majority decision once it is taken.

Time rule: a nominated timekeeper plus agreed checkpoints prevents good plans from ending as incomplete tasks, which score low.

Safety and ethics rule: refusing an unsafe or dishonest shortcut is recorded as reliability, whereas completing the task by cheating is penalised.