Cataract:
1. is abnormal curvature of cornea
2. is loss of elasticity of the lens
3. occurs often in children
4. involves increased opacity of the lens

A condition in which close objects appear clearly, but far ones don't is called as:
1. Hyperopia
2. Myopia
3. Presbyopia
4. Glaucoma

Identify the incorrect statement regarding rods and cones:
1. Rods are more sensitive to light than cones
2. There are more rods than cones in the retina
3. Cone vision provides higher acuity than rod vision
4. Rods are found primarily in the fovea while cones are more scattered throughout the retina

Branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron are the:

Nerve cells within the nervous system responsible for converting external stimuli from the organism's environment into internal electrical impulses are:

1. association

2. sensory

3. motor

4. interneurons

In the CNS, myelin sheaths around neurons are formed by:

1. Schwann cells
2. microglia
3. astrocytes
4. oligodendrocytes

The change in membrane potential that returns it to a negative value just after an action potential has changed the membrane potential to a positive value is called as:

During the absolute refractory period along an axon membrane of a neuron, __________.
1. the potassium gates are open and K+ is diffusing down its concentration gradient
2. the sodium gates are closed and Na+ us diffusing down it concentration gradient
3. the neuron is unable to respond to a stimulus of any intensity
4. the membrane is most sensitive to stimuli

What is meant by the fact that the nerve impulses are conducted along an axon without decrement?
1. The action potentials are conducted at the same velocity.
2. The action potentials alter the threshold potential
3. The action potentials are conducted without decreasing amplitude
4. The action potentials will be produced by hyperpolariztion.

Electrical synapses differ from the chemical synapse in that they:

1. occur when two cells are joined by integrin proteins
2. are characterized by a synaptic cleft
3. occur between two cells of unequal size
4. require the presence of gap junctions