requirements for human life

Requirements for Human Life

Humans have been acclimating to life on Earth for approximately 200,000–300,000 years, needing air, water, food, and suitable temperature and pressure ranges for survival.

Oxygen

Key component of chemical reactions that produce energy in the body; atmospheric air contains about 20% oxygen.

Nutrient

A substance in foods and beverages that is essential to human survival.

Macronutrients

Nutrients required in large amounts, including carbohydrates, lipids (fats), and proteins.

Micronutrients

Vitamins and minerals needed in small amounts for essential chemical reactions and processes.

Narrow Range of Temperature

Body temperature must be maintained close to 37°C (98.6°F) for essential chemical reactions to occur.

Controlled Hypothermia

Clinically induced hypothermia to reduce metabolic needs, often used during surgeries.

Atmospheric Pressure

Pressure exerted by gases in the Earth's atmosphere, necessary for breathing and keeping blood gases dissolved.

Decompression Sickness (DCS)

Condition caused by rapid reduction in barometric pressure, leading to nitrogen bubbles forming in the blood.

Pressure

A force exerted by a substance that is in contact with another substance.