PRELIMS
Important Biological One-Liners and Facts
Miscellaneous biological facts and scientific terms essential for general awareness and scientific aptitude.
I. Scientific Studies and Terms
- Oneirology: The study of dreams.
- Kalology: The study of human beauty.
- Osteology: The study of bones.
- Ondontology: The study of teeth.
II. Human Body Superlatives and Records
- Strongest Part: Enamel of the teeth.
- Fastest Nerve Speed: 532 kmph.
- Lungs Area: Internal area is 93 sq. m. (40x external body surface).
- Uterus Weight: 50g (never pregnant) to 100g (after birth).
- Small Intestine: ~7 meters long; 2.5 cm diameter.
- Blood Circulation Time: ~23 seconds to circulate the entire body.
- Heart Pump Rate: 4.5 liters per minute.
- Largest Gland: Liver.
- Largest Endocrine Gland: Thyroid.
- Blood pH: Slightly alkaline, 7.35–7.45.
- RBC Lifespan: ~120 days; destroyed in the Spleen (the "graveyard of RBCs").
- WBC Lifespan: 1–15 days (varies by type).
III. Physiological Facts
- Breathing: An adult takes ~500 ml air per breath; ~350 liters of oxygen daily.
- Oxygen Transport: 97% by Haemoglobin, 3% by Plasma.
- Respiration Timing: 5 seconds total (2s inspiration, 3s expiration).
- Antibiotics: Penicillin is obtained from the Penicillium fungus.
- Intelligence: Human is the most intelligent hominid.
- Heart Rate: Child's heart beat > Adult's.
IV. Reproductive Biology
- Sex Determination: Depends on Male chromosomes (XY) not the female (XX).
- Pregnancy Testing: Detection of H.C.G. (Human Chorionic Gonadotropin) hormone in urine.
V. Evolution and Creation
- Initial Life: There was no oxygen at the time of the creation of life.
- Cell Turnover: ~150 lakh (15 million) cells are destroyed per second.
UPSC Relevance
Miscellaneous one-liners often appear as factual statements in Prelims.
- Physiological Ratios: Understanding the oxygen transport split (97:3) and heart pump capacity.
- Evolutionary Biology: Recognizing that the early atmosphere was reducing (no free ).
- Medical Diagnostics: The role of HCG in pregnancy kits.