Nervous System

Each hemisphere has a superficial layer of “grey matter” called the cerebral cortex, lying over “white matter”.

Multipolar are most common in the CNS. Motor neurons, whose cell bodies lie within the spinal cord, are multipolar.

Sensory neurons are unipolar. And their cell bodies are outside the CNS in the dorsal root ganglia.

Sounds of the highest frequencies travelling through the endolymph displace that part of the basilar membrane that is close to the oval window. As frequency gets lower, progressively more distant sections of the basilar membrane are displaced. Choice B is correct but not as good an answer as choice D.

The eye can accommodate its lens to clearly see objects at any distance from the eye.

Afferent means “incoming”. Incoming information travels from the body’s sensors to the brain carrying sensory information.

Red cones are most sensitive to light with wavelength 560 nm, green cones at 530 nm and blue cones at 420 nm.

The hypothalamus is the main visceral control centre of body homeostasis. The thalamus receives sensory information before passing it onto basal nuclei and cerebral cortex.

The inferior colliculi receive auditory stimuli via the medulla oblongata. The superior colliculi receive visual sensation.

To focus on a distant object, the lens must be pulled into a thin profile by the ciliary fibres being taut. This occurs when the ciliary muscles recedes from the lens as it relaxes.