Cochlea of mammalian internal ear is concerned with
hearing
balance of body posture
both (a) and (b)
perception changes of atmospheric pressure
A.
hearing
The cochlea is a portion of the inner ear that looks like a snail shell (cochlea is Greek for snail.) The cochleareceives sound in the form of vibrations, which cause the stereocilia to move. The stereocilia then convert these vibrations into nerve impulses which are taken up to the brain to be interpreted.
A person who shows unpredictable moods, outbursts of emotion, quarrelsome behaviour and conflicts with others is suffering from
borderline personality disorder (BPD)
mood disorder
addictive disorder
schizophrenia.
Given below is a table comparing the effects of sympathetic and parasympathetic nervous system
for four feature (a-d). Which one feature is correctly described
| Feature | Sympathetic nervous system | Parasympathetic nervous system |
| a) Salivary glands | Stimulate Secretion | Inhibit Secretion |
| b) Pupil of the eye | Dilate | Constricts |
| c) Heart rate | Decreases | Increases |
| d) Intestinal peristalsis | Stimulates | Inhibits |
Cerebrospinal fluid is present
beneath the pia mater
between piamater and arachnoid
between arachnoid and duramater
between duramater and cranium
Unidirectional transmission of a nerve impulse through nerve fibre is due to the fact that
nerve fibre is insulated by a medullary sheath
sodium pump starts operating only at the cyton and then continues into the nerve fibre
neurotransmitters are released by dendrites and not by axon endings
neurotransmitters are released by the axon endings and not by dendrites.
The dendrite carries impulses
towards the cyton
away from cyton
across the body
from one neuron to another
The total number of nitrogenous bases in human genome is estimated to be about
3.5 million
35 thousand
35 million
3.1 billion.
Examine the diagram of the two cell types A and B given below and select the correct option
A B
Cell A is the rod cell found evenly all over retina
Cell A is the cone cell more concentrated in the fovea central is
Cell B is concerned with colour vision in bright light
Cell A is sensitive to low light intensities
A person is wearing spectacles with concave lenses for correcting vision. While not using the glasses, the image of a distant object in his case will be formed
on the blind spot
behind the retina
in front of the retina
on the yellow spot
