Amnesia can occur as a result of head trauma, drug toxicity, stroke, Alzheimer disease, infection or even emotional shock.
Determining which categories an organism falls into is no easy matter. In general, physical characteristics determine grouping.
The sound barrier is just a certain velocity relative to the surrounding environment, not an actual membrane to be penetrated by a jet's nose. Yet we have photos.
Like sneezing, goose bumps (also known as the pilomotor reflex) represent one of your body's automatic responses, meant to increase your chances of survival in the harsh world.
Eyelashes protect the eye from foreign particles and act as sensors to let the brain know a potentially painful poking could be imminent.
How old is the Earth? Measurements made in the 18th century were based on the rate of the Earth's cooling and vastly underestimated the age of the Earth to be in the hundreds of thousands of years.
The complexity of the task requires a fairly inconceivable 100 billion neurons, interconnected via trillions of synapses.
The frozen burrito in your microwave oven sits in an electromagnetic field, bombarded on all sides by high-frequency microwaves.
Cancer involves a group of rapidly growing, abnormal cells. This growth can occur in the breast tissue of either gender. Cancer does not discriminate.
Psychologists are far from a consensus on how to measure vague concepts like creativity and intelligence.
If plate tectonics followed the laws of Hollywood physics, Los Angeles would be tearing violently from the mainland as we speak.
Electrons were once thought to orbit a nucleus much as planets orbit the sun. That picture has since been obliterated by modern quantum mechanics.