Test: Neural Control And Coordination - 1

Nassl’s grains are mainly present in cyton and dendrite. These granules are rough endoplasmic reticulum with rosettes of free ribosome, the site for protein synthesis. It is absent in axon.

Thalamus is the part of brain that acts as relay centre to receive and transmit general sensations except smell. Thalamus is located in the forebrain superior to the midbrain.

The hypothalamus performs many functions which are important for the survival and enjoyment of life. It serves as a link between 'mind' and body and between nervous and endocrine system. The hypothalamus is responsible for hormone production. The hormone produced by this area govern body temperature thirst hunger, sleep, circulation rhythm, mood sex drive etc. This area of the brain also controls the functioning of the pituitary gland. Thus, if any injury localised to the hypothalamus it will disrupt the complete regulation of body temperature and other activities.

In prosencephlon, the first and second ventricles open into third ventricles by foramen of Monro. It is the opening that connects the left and right sides of lateral ventricle in brain.

Brain cavities are filled with cerebrospinal fluid (CSF). In subarachnoid space, the CSF acts as shock proof cushion to prevent in injury in case of accident.

The cristae present in internal ear is responsible for dynamic equilibrium. Cerumen is responsible for lubrication and protection. Organ of corti is responsible for hearing and maculae is responsible for static equilibrium of the body.

Nerve fibres are specialized to transmit impulses form one part of the body to other. Nerve fibres do not shows the property of elasticity and contractility.

There are different kinds of stimulus that is received by different receptors in our body. Hearing of sound of bell is conditioned stimulus and salivation in response to bell is conditioned response. Food itself is conditioned stimulus and salivation in response to food is unconditioned response.

Gustatoreceptors are responsible for the sense of taste. Gustatory receptors are located inside taste buds on the tongue.

Hypothalamus helps to maintain homeostasis by controlling hunger, thirst, blood pressure, temperature, feeling etc. So, it is important link between nervous system and endocrine system.

The reflex pathway comprises at least one afferent neuron (receptor) and one efferent (effectoror exciter) neuron appropriately arranged in a series. The (iii) and (iv) shows gray and white matter.

Eye donation process involves grafting of cornea of dead man’s eye, which is stored and grafted on another person’s eye to restore vision.

Brain stem is the support system of brain and is the collective name for medulla, pons, midbrain and diencephalon. Brain stem also connect the brain with spinal cord.

The optic nerves leave the eye and the retinal blood vessels enter it at a point medial to and slightly above the posterior pole of the eye ball. Photoreceptor cells are not present in that region and hence it is called the blind spot.

Neurohypophysis is not a true endocrine gland which is also called as a posterior lobe or pituitary gland because it is only a hormone storage area that receives hormones from the hypothalamus for release. Oxytocin and vasopressin produced in the hypothalamus are released by posterior pituitary.
So, the correct option is 'It secretes neurohormones.'

Unipolar nerves are present in nerves of embryonic stage. Mixed nerves are found in all the spinal nerves. Bipolar nerves are present in nerve cells of retina. Multipolar nerves are present in nerve cells of cerebral cortex.

The vestibular apparatus is composed of three semicircular canals and the otolith organ consisting of the saccule and utricle

Hypophysis is a part of pituitary gland. Modulator is present in brain and spinal cord. Receptor is located in sense organs. Effectors are muscle and glands that bring about movement.

Motor neuron carry impulse from CNS to effector. Axon carry impulse away from cyton. Afferent neuron carry impulse from receptor to CNS and dendrite carry impulse towards cyton.

The coiled portion of the labyrinth is called cochlea. The membranes constituting cochlea, the reissner’s and basilar, divide the surounding perilymph filled bony labyrinth into an upper scala vestibuli and a lower scala tympani. The space within cochlea called scala media is filled with endolymph. At the base of the cochlea, the scala vestibuli ends at the oval window, while the scala tympani terminates at the round window which opens to the middle ear.