Nervous System
How does accommodation in the eye occur? When our ciliary muscle:
Contracts and the tension on the ciliary fibres increases allowing a rounder lens
Relaxes and the tension on the ciliary fibres decreases allowing a rounder lens
Relaxes and the pull of our ciliary fibres flattens the lens
Contracts and the pull of our ciliary fibres flattens the lens
Relaxes and the pull of our ciliary fibres flattens the lens
The ciliary muscle is doughnut-shaped with the lens in the “hole” and attached to the muscle by ciliary fibres (zonules). When the ciliary muscle relaxes, it moves away from the lens (the diameter of the hole increases) which causes the ciliary fibres to pull on the lens. This tension in the fibres stretches and flattens the lens into a less convex shape.
Relaxes and the pull of our ciliary fibres flattens the lens The ciliary muscle is doughnut-shaped with the lens in the “hole” and attached to the muscle by ciliary fibres (zonules). When the ciliary muscle relaxes, it moves away from the lens (the diameter of the hole increases) which causes the ciliary fibres to pull on the lens. This tension in the fibres stretches and flattens the lens into a less convex shape.
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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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