The Function of the Iris Is to ____

question 1

Multiple Choice

The function of the iris is to ____.

• A) control the amount of light entering the eye
• B) focus the image on the retina
• C) respond to particular colors
• D) keep the lens under tension to allow for image focusing
• E) prevent light scattering upon entry to the eye

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Definitions:

Oldest Rocks

The earliest-formed rocks on Earth or within a specific geological setting, often found in the deepest layers of the Earth's crust.

Mass Extinctions

Significant global events in the Earth's history where large percentages of species die out in a relatively short period of time, often due to catastrophic environmental changes.

Geologic Timescale

A method of dating based on the chronological correlation of Earth's geological layers to time, utilized by geologists for depicting the sequence and association of historical events on Earth.

Seafloor Spreading

The process by which new oceanic crust is formed at mid-ocean ridges and slowly moves away from them.