Nervous System
The human eye is able to alter its focal length in a process called accommodation. Choose the best description of accommodation from the ones below. When the ciliary muscle:
Relaxes, the ciliary fibres are loosened and the eye lens is stretched into a long focal length.
Contracts, the ciliary fibres are pulled taut and the eye lens is stretched into a long focal length.
Relaxes, the ciliary fibres are pulled taut and the eye lens oozes into a short focal length.
Contracts, the ciliary fibres are loosened and the eye lens oozes into a long focal length.
Contracts, the ciliary fibres are loosened and the eye lens oozes into a long focal length.
When the ciliary muscle contracts, it forms a smaller diameter circle around the lens causing the fibres that connect it to the lens to slacken, which allows the elastic lens to recoil (ooze) into a rounder shape. This has a shorter focal length.
Contracts, the ciliary fibres are loosened and the eye lens oozes into a long focal length. When the ciliary muscle contracts, it forms a smaller diameter circle around the lens causing the fibres that connect it to the lens to slacken, which allows the elastic lens to recoil (ooze) into a rounder shape. This has a shorter focal length.
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In the spinal cord, the ascending tracts contain:A. White matter and transmit sensory information
B. White matter and transmit motor commands
C. Grey matter and transmit sensory information
D. Grey matter and transmit motor commands
Which sequence of ion movements describes the action potential?
A. Na+ move out of cell then K+ move in
B. K+ move in to cell then Na+ move out
C. K+ move out of cell then Na+ move in
D. Na+ move into cell then K+ move out
Which of the following substances is prevented from entering the brain by the blood-brain barrier?
A. Glucose
B. Nicotine
C. Pharmaceuticals
D. Alcohol
There are three ossicles in the middle ear. What are their names?
A. Malleus, stapedius, otolith
B. Cochlea, stapes, incus
C. Stapedius, ampulla, cochlea
D. Malleus, stapes, incus
The inner ear (or internal ear) may be described as a series of tubes. What are the tubes filled with?
A. Air
B. Perilymph
C. Endolymph
D. Perilymph and endolymph
What characterises a spinal reflex?
A. It involves rapid processing by the brain and a predictable response.
B. It is a predictable, unlearned and involuntary motor response.
C. It is a rapid, predictable, learned and involuntary motor response.
D. It involves stimulation of a motor neurone by a sensory neurone that originates within the CNS.
A multipolar neuron has more than one of what?
A. Dendrite attached to the cell body
B. Axon attached to the cell body
C. Synaptic terminal attached to the axon
D. Cell body
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