Case Study: Tibetans

Acclimate

The process of the body adjusting to a change in environment, such as higher altitude.

Erythropoietin (EPO)

A hormone released by the kidneys that stimulates the production of red blood cells.

Hyperventilation

An increase in the rate and depth of breathing, often as a response to lower oxygen levels.

Phenotypic plasticity

Shifts in an organism's body, physiology, or behavior that depend on environmental conditions, not genetic changes.

Oxygen availability at higher altitudes

Oxygen levels decrease by approximately 17% when traveling from sea level to Denver.

PAO2

The partial pressure of oxygen in arterial blood.

Low arterial PO2

A condition where the oxygen levels in arterial blood are lower than normal.

Tibetan Highlanders

People adapted to living at high altitudes, capable of functioning with lower oxygen levels.

Adaptations in Tibetans

Physiological mechanisms evolved to handle low oxygen environments.

Gene versions in Tibetans

Genetic variations that lead to the production of fewer red blood cells.

Fetal mortality

The rate of death of unborn fetuses, which can be affected by blood thickness due to excessive red blood cells.

EPAS1

A stretch of DNA that controls red blood cell production, altered in Tibetans for adaptation.

Natural selection

The process through which organisms adapt to their environment based on heritable changes that increase survival.

Oxygenation of cells

The process of providing oxygen to cells, essential for their function.

Red blood cells

Cells in the blood that carry oxygen from the lungs to the rest of the body.

Heart rate increase

A common physiological response to high altitudes, where the heart beats faster to circulate blood.

Dizziness at high altitude

A sensation that can occur due to decreased oxygen levels affecting brain function.

Rapid breathing

An increase in the frequency of breaths taken as a response to lower oxygen availability.

Tibetan adaptation time frame

Tibetans have adapted to high altitudes in less than 3000 years, showcasing rapid evolution.

Gene comparison study

Analysis comparing the genomes of ethnic Tibetans and Han Chinese to identify genetic adaptations.

Altitude impact on physiology

The effect of increased elevation on the body's physiological functions, particularly respiratory and cardiovascular responses.