Multiple Choice QuestionsNow-a-days cornea transplantation is very popular. The reason is that it
is easy to preserve
transplanted very easily
can be easily obtained
does not link with blood supply and immune system
D.
does not link with blood supply and immune system
Cornea transplantation is very popular these days because the cornea has no blood supply, so it is away from the immune system of the body.
Ventricles are related to
heart only
brain only
both 'a' and 'b'
none of these
C.
both 'a' and 'b'
Ventricles are related to both heart and brain. Mammalian heart is four chambered. The upper two chambers known as right and left auricle and the lower as right and left ventricles. In brain there are four ventricles. Ventricle Ist and II (lateral ventricles) are cavities of two cerebral hemispheres. IIIrd ventricle (diocoel) is cavity of diencephalon and IV ventricle (metacoel) is cavity of medulla oblongata.
If a stimulus, several times greater than the threshold stimulus is provided to a muscle fibre, it will
contract with a larger force
contract with a smaller force
contract with the same force
undergo tetany.
C.
contract with the same force
A muscle fibre would contract only when it receives stimulation of certain intensity called threshold stimulus. Response of a muscle fibre to a stimulus is not proportional to its intensity. It is absent when the intensity is subliminal. Muscle fibre contracts to the maximum whether the stimulus has threshold value or supraliminal value.
Organ of Corti is found in
heart
kidneys
inner ear
nasal chamber
C.
inner ear
Organ of Corti are found in cochlear channel (internal ear) and are responsible for hearing. Ear is concerned both with hearing and balance, semicircular canals are responsible for balance when body is in motion.
Assertion : The imbalance in the concentration of Na+, K+ and proteins generates the resting potential.
Reason : To maintain the unequal distribution of Na+ and K+, the neurons use electrical energy.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both the assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both the assertion and reason are false.
C.
If assertion is true but reason is false.
To maintain the unequal distribution of Na+ and K+ ion, the neuron uses chemical energy in the form of ATP to actively transport Na+ ion out of the cell and move K+ inside the cell.
Which of the following is the part of mid brain of rabbit?
Diencephalon
Cerebrum
Corpora quadrigemina
None of the above
C.
Corpora quadrigemina
The dorsal part of mid brain (mesencephalon) is in the form of two pairs (i.e., four) of spherical optic lobes (corpora quadrigemina) located behind the pineal body optic lobes are reduced merely as reflex centres of visual and auditory.
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.
D.
neurotransmitters are released by the axon endings and not by dendrites.
Neurotransmitters are molecules that fit like a lock and key into a specific receptor. The receptor is located on the next cell in the line. Therefore, nerve impulses cannot travel in the opposite direction, because nerve cells only have neurotransmitter storage vesicles going one way, and receptors in one place.
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
C.
in front of the retina
As the person uses spectacles having concave lens, he must be suffering from myopia or short-sightedness. Here the eyeballs become elongated, so that parallel rays are focussed in front of retina.
Myopia is an eye disorder where light focuses in front of retina. This causes distant objects appear normal. It is also known as short- sightedness.
The total number of nitrogenous bases in human genome is estimated to be about
3.5 million
35 thousand
35 million
3.1 billion.
D.
3.1 billion.
Genome size is usually stated as the total number of base pairs; the human genome contains roughly 3 billion base pairs.
Sella Turcica is found
in bones
in joints
nearby pituitary
nearby thyroid
C.
nearby pituitary
Sella turcica is found in the sphenoid bone behind the chiasmatic groove and tuberculum sellae. Pituitary is present in it. It is a depression in sphenoid bone of cranial cavity.
