Science Source December 28, 2009 DVD

Narbona Pictograph Panel, Canyon de Chelly National Monument, Chinle, Arizona. This pictograph done by an unknown Navajo artist (perhaps Dibe Yazhi "L...

Test tube samples of venous blood (returning to the heart in veins), and arterial blood (carrying blood away from the heart) .

45 year old female patient with black eye; closed and showing bruising.

Blackened fingernail on man's index finger.

A school nurse tests kids' eyes.

Bleeding cut on finger.

Students on a running track taking their pulse using a stop watch. The pulse is measured by counting the number of times the artery throbs per minute....

Ptolemy (87 - 150 AD). A Greek living in Alexandria, Ptolemy extended Hipparchus' theory of the solar system. Ptolemy's system involved at least 80 ep...

View across the Ceremonial Plaza to Kukulcan's Pyramid in the Mayan ruins in Mayapan, Mexico. The Mayan capital was at its height from the 1220s to 14...

Temple of the Jaguar Masks in Lamanai. Lamanai was an ancient Mayan city located in northern Belize.

Olmec Head, Museum Park, Villahermosa, Mexico. Villahermosa is the capital city of the Mexican state of Tabasco. The Olmec were an ancient civilizatio...

Olmec Head, Museum Park, Villahermosa, Mexico. Villahermosa is the capital city of the Mexican state of Tabasco. The Olmec were an ancient civilizatio...

An example of an image from the Rorschach inkblot test.

An example of an image from the Rorschach inkblot test.

An example of an image from the Rorschach inkblot test.

An example of an image from the Rorschach inkblot test.

An example of an image from the Rorschach inkblot test.

An example of an image from the Rorschach inkblot test.

Diagram showing emmetropia, the normal state of vision in which the eye lens is neutral and objects more than twenty feet away are sharply in focus.

Diagram showing myopia, a defect of the eyes in which the eyeball is too long, or the cornea overly curved. This leads to images being focused in fron...

Diagram showing the correction of myopia with the use of a concave lens. Myopia is a defect of the eyes in which the eyeball is too long, or the corne...

Diagram showing hyperopia, a defect of the eyes in which the eyeball is too short, or in which the lens is not round enough. This leads nearby objects...

Diagram showing the correction of hyperopia with the use of a convex lens. Hyperopia is a defect of the eyes in which the eyeball is too short, or in...

Uxmal, ruins of a pre-Columbian Mayan civilization located south of present-day Merida, Yucatan, Mexico.

A baby in an operant conditioning chamber, also known as a Skinner Box. It is named after its inventor, B.F. Skinner.

A baby in an operant conditioning chamber, also known as a Skinner Box. It is named after its inventor, B.F. Skinner.

A baby in an operant conditioning chamber, also known as a Skinner Box. It is named after its inventor, B.F. Skinner.

Woman pinching body fat.

Open MRI scanner. MRI (magnetic resonance imagine) is a diagnostic technique that produces cross-sectional images of parts of the body and is particul...

A photomontage showing different medical imaging techniques, including x-ray, MRI, and CT scans.

A photomontage showing different medical imaging techniques, including x-ray, MRI, and CT scans.

A photomontage showing different medical imaging techniques, including x-ray, MRI, and CT scans.

A photomontage showing different medical imaging techniques, including x-ray, MRI, and CT scans.

A photomontage showing different medical imaging techniques, including x-ray, MRI, and CT scans.

Hand with stopwatch. A stopwatch is a timepiece that can be stopped and started to measure exact intervals of time.

A young boy takes the Stanford-Binet intelligence test.

A teenage girl takes the TAT (Thematic Apperception Test) test with photos.

A young boy takes the Stanford-Binet intelligence test.

A young boy takes the Stanford-Binet intelligence test.

A boy takes the Rorschach inkblot test.

A teenage boy takes the Rorschach inkblot test.

A boy takes the TAT (Thematic Apperception Test) test with photos.

A boy takes the TAT (Thematic Apperception Test) test with photos.

A teenage boy takes the TAT (Thematic Apperception Test) test with photos.

A young girl takes the Rorschach inkblot test.

A teenage girl takes the TAT (Thematic Apperception Test) test with photos.

A teenage boy takes the TAT (Thematic Apperception Test) test with photos.

A young girl takes the Rorschach inkblot test.

Isis Temple at Philae. The right pylon, with reliefs of Isis and Horus. The Ancient Egyptian Philae Temple was originally constructed on the island of...

Isis Temple at Philae, with reliefs of Isis and Horus. The Ancient Egyptian Philae Temple was originally constructed on the island of Philae, but has...