When an Electron Has Been Excited to a Higher Energy

question 9

Multiple Choice

When an electron has been excited to a higher energy state,it can then drop back to the original level,re-emitting the light as fluorescence.When chlorophyll is extracted in solution,and a bright red or blue light is shown on it,the chlorophyll fluoresces brightly.However,when the chlorophyll is packaged inside chloroplasts and the red or blue light is turned on,there is no fluorescence.This most likely indicates that

• A)the red and blue light waves are reflected by the chlorophyll membrane.
• B)chlorophyll in solution is a different molecule than chlorophyll in a chloroplast.
• C)excited electrons are transferred to electron acceptors in the chloroplast.
• D)fluorescence does not work in living cells.
• E)green light must be used to make living cells fluoresce.

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Definitions:

Ejaculation

The release of semen from the male reproductive system.

Erection

The physiological process whereby erectile tissue fills with blood, causing the penis or clitoris to become enlarged and firm, typically in response to sexual arousal.

Circumcision

The surgical removal of the foreskin from the penis.

Foreskin

The retractable fold of skin covering the tip of the penis in uncircumcised males.