2018 source guide · Biology

NEET 2018 Biology Human Physiology Questions

Use this page to connect the official 2018 paper with current Biology practice. NeetVellum does not claim a chapter appeared in that paper until the official question and final key have been mapped.

Practice 639 verified questions →Check official NTA archive ↗

What to master

integrated respiratory, circulatory, excretory, neural, endocrine and movement physiology.

Original practice preview

These are current-syllabus NeetVellum questions, shown separately from historical-paper provenance.

Example 1 · difficulty 3/5

An Rh negative woman married to an Rh positive man delivers her first child without complications, but during a later pregnancy the foetus develops severe haemolysis. The underlying cause of this condition is:

A. ABO blood group mismatch between the mother and the foetus
B. Anti-Rh antibodies formed by the mother during the first pregnancy entering the foetus in the next pregnancy
C. Rh antigens of the mother attacking antibodies inherited by the foetus from the father
D. Maternal vitamin B12 deficiency leading to abnormal erythropoiesis in the foetus

Example 2 · difficulty 1/5

The human trachea is held open by C-shaped cartilaginous rings that are incomplete dorsally. The most appropriate reason for this incomplete (C-shaped) arrangement is that it:

A. allows the ciliated epithelium to beat freely over the entire circumference
B. permits the trachea to collapse completely during forced expiration
C. keeps the airway patent while allowing the adjacent oesophagus to bulge during swallowing
D. enables the rings to secrete surfactant that lowers surface tension

Example 3 · difficulty 2/5

Alveolar air has a pO₂ of about 104 mm Hg, while the deoxygenated blood reaching the alveolar capillaries has a pO₂ of about 40 mm Hg. As a direct consequence of this gradient:

A. oxygen diffuses from the alveoli into the capillary blood until it equilibrates near 95 mm Hg
B. oxygen is pumped from the capillaries into the alveoli by active transport
C. carbon dioxide simultaneously diffuses from the alveoli into the blood
D. oxygen remains confined to the alveoli because the respiratory membrane is impermeable to gases

The evidence-first practice loop

1. Verify provenanceOfficial paper and final key before accepting a PYQ label.
2. Attempt closed-bookExpose the concept or execution gap before rereading.
3. Repair and returnClassify the miss and re-practice after a delay.

Canonical chapter practice

Breathing and Exchange of Gases →Body Fluids and Circulation →Excretory Products and their Elimination →Locomotion and Movement →Neural Control and Coordination →Chemical Coordination and Integration →

Frequently asked questions

Are these official NEET 2018 Biology Human Physiology PYQs?

No. The previews are original NeetVellum practice questions. A historical item receives a PYQ label only after its official paper and authoritative final answer key are attached. Use the official archive for the source paper.

How should I use the NEET 2018 paper?

Solve the official paper under its original timing, verify against the final key, classify every miss, and then use the linked current-syllabus practice bank to repair the exposed concept.