Crossing-Over

question 21

Multiple Choice

Crossing-over

• A) involves the physical exchange of parts of homologous chromosomes.
• B) occurs during mitosis.
• C) involves the fusion of gametes to restore the diploid number of chromosomes.
• D) occurs in somatic cells.

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Definitions:

Retina

The light-sensitive layer of tissue at the back of the eye that captures images and sends visual information to the brain.

Rods

Photoreceptor cells in the retina of the eye that are responsible for vision at low light levels.

Bipolar Cells

A type of neuron found in the retina of the eye that acts as an intermediary between photoreceptor cells and ganglion cells, playing a key role in the visual process.

Cornea

The transparent front part of the eye that covers the iris, pupil, and anterior chamber, responsible for focusing most of the light that enters the eye.