Which part of the human ear plays no role in hearing as such but is otherwise very much

required?

1. Eustachian tube

2. Organ of Corti

3. Vestibular apparatus

4. Ear ossicles

The purplish red pigment rhodopsin contained in the rods type of photoreceptor cells of

the human eyes is a derivative of

1. vitamin-C

2. vitamin-D

3. vitamin-A

4. vitamin-B

When a neuron is an resting state, ie, not conducting any impulse, the axonal membrane

is

1. equally permeable to both Na⁺ and K⁺ ions

2. impermeable to both Na⁺ and K⁺ ions

3. comparatively more permeable to K⁺ ions and nearly impermeable to Na⁺ ions

4. comparatively more permeable to Na⁺ ions and nearly impermeable to K⁺ ions

The nerve centres which control the body temperature and the urge for eating are

contained in 

1. hypothalamus 

2. pons

3. cerebellum 

4. thalamus 

Alzheimer disease in humans is associated with the deficiency of

1. dopamine

2. glutamic acid

3. acetylcholine

4. Gamma Amino Butyric Acid (GABA)

The kind of tissue that forms the supportive structure in our pinna (external ears) is also

found in

1. vertebrae

2. nails

3. ear ossicles

4. tip of the nose

Given below is a diagrammatic cross section of a single loop of human cochlea.

Which one of the following options correctly. represents the names of three different

parts?

1. B : Tectorial membrane
    C: Perilymph
    D : Secretory cells

2. C: Endolymph
    D : Sensory hair celis
    A: Serum

3. D: Sensory hair cells
    A: Endolymph
    B: Tectorial membrane

4. A : Perilymph
    B: Tectorial membrane
    C: Endolymph

Which one of the following is the correct difference between rod cells and cone cells of our retina? 

During the propagation of a nerve impulse, the action potential results from the movement of

1. K⁺ ions from extracelular fluid to intracellular fluid

2. Na⁺ ions from intracellular fluid to extracellular fluid

3. K⁺ ions from intracellular fluid to extracellular fluid

4. Na⁺ ions from extracellular fluid to intracellular fluid

Cornea transplant in humans is almost never rejected. This is because

1. its cells are least penetrable by bacteria

2. it has no blood supply

3. it is composed of enucleated cells

4. it is a non-living layer