L1 Is an IgSF Molecule That Has Been Shown to Be

question 19

Multiple Choice

L1 is an IgSF molecule that has been shown to be important in neural development; it is thought that it may be involved in axon growth within the embryonic nervous system. What evidence supports this statement?

• A)L1 mutants always die.
• B)L1 mutants show deficits in their vision.
• C)People who die of L1-deficiency are often missing two large nerve tracts connecting brain/spinal cord regions.
• D)People who die of L1-deficiency are often missing a significant portion of their brain.
• E)People who die of L1-deficiency are often missing a significant portion of their spinal cord.

Understand and apply the change-of-base formula.

Apply logarithmic properties to solve equations.

Use logarithmic properties for expansion and condensation.

Calculate with logarithms without a calculator.

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Definitions:

Rods

Specialized photoreceptor cells in the retina that are responsible for vision at low light levels.

Rhodopsin

A light-sensitive pigment found in rod cells of the retina, crucial for vision in low light conditions.

Semicircular Canals

Three fluid-filled tubes in the inner ear that help maintain balance by detecting changes in head rotation and motion.

Liquid

A state of matter with a definite volume but no fixed shape, that flows and adapts to the shape of its container.