A. To protect the eye
B. To focus light onto the retina
C. To control the amount of light entering the eye
D. All of the above
A. They create the electrical charge of the impulse
B. They transmit the impulse across the synapse
C. They control the strength of the impulse
D. They regulate the frequency of impulses
A. By diffusion
B. By active transport
C. By facilitated diffusion
D. By saltatory conduction
A. Sodium ions
B. Calcium ions
C. Potassium ions
D. Chloride ions
A. 1950s and 1960s
B. 1970s and 1980s
C. 1980s and 1990s
D. 1990s and 2000s
A. 1950s and 1960s
B. 1970s and 1980s
C. 1980s and 1990s
D. 1990s and 2000s
A. To transmit information throughout the body
B. To create energy
C. To produce hormones
D. To control muscle movement