Reflex action ( withdrawal of hand from heat source ) is controlled by Spinal cord Answer : (d)

The facial nerve is the seventh cranial nerve, or simply cranial nerve VII. It Sensory, motor and PSNS Answer : (c)

Between the axon ending and the dendrite of the next neuron is a very tiny gap called the synapse Answer : (a)

Answer : (a)

Organs of Ruffini act as thermo-receptors that respond for a long time Answer : (c)

Fluid found between piamater and arachnoid is Cerebrospinal fluid Answer : (b)

The blood–brain barrier consists of endothelial cells lining brain capillaries. It serves to restrict and control the movement of substances between the general circulation and brain extracellular fluid. It participates in regulating the volume and composition of fluid surrounding the brain through specific transport processes, and thus contributes to homoeostasis of the central nervous system. The barrier function of the blood–brain barrier is due to: (1) tight junctions that restrict movement of substances between the endothelial cells, (2) specific transport proteins that determine which substances can cross the barrier transcellularly and (3) enzymes that may degrade or alter substances prior to passage. Answer : (d)

Answer : (a)

The organ of Corti is located in the scala media of the cochlea of the inner ear between the vestibular duct and the tympanic duct and is composed of mechanosensory cells, known as hair cells. Answer : (a)

The autonomic nervous system is a control system that acts largely unconsciously and regulates bodily functions such as the heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. Answer : (b)

Mechanoreceptor: A sense organ or cell that responds to mechanical stimuli such as touch or sound. Pinna – auditory canal – tympanic membrane – malleus – incus – stapes – cochlea – auditory nerve Answer : (c)

Amplitude is proportional to the strength of the stimulus. Amplitude is generally small. No refractory period is associated with graded potentials. Answer : (c)

The acoustic reflex is an involuntary muscle contraction that occurs in the middle ear in response to high-intensity sound stimuli or when the person starts to vocalize.Spinal cord is main component of reflex action. Answer : (a)

Sound is transmitted from middle ear to internal ear due to striking of stapes Answer : (c)

The hippocampus deals with the formation of long-term memories and spatial navigation. Answer: (d)

Humans cannot make Rhodopsin, instead they use and external source, b-carotene, that is found in food in order to synthesis it: Answer : (a)

Light enters the eye through the pupil, and the iris regulates the amount of light by controlling the size of the pupil. Answer : (c)

Diencephalon develop in adult as Epithalamus, Thalamus, Hypothalamus, Subthalamus, Pituitary, Pineal, Third ventricle Telencephalon: develop in adult as Rhinencephalon, Amygdala, Hippocampus, Cerebrum(Cortex), Basal Ganglia,Lateral ventricles Myelencephalondevelop in adult asMedulla Oblongata Metencephalon develop in adult as Pons, Cerebellum Mesencephalon develop in adult as Tectum, Cerebral peduncle, Pretectum, Cerebral aqueduct Answer : (a)

Nerve axon takes part in conduction of impulse Answer : (c)

In higher vertebrates (reptiles, birds, mammals) there are 12 pairs of cranial nerves: Lower vertebrates (fishes, amphibians) have 10 pairs. Answer : (c)

Repletion is a condition of being completely full of something Rhodopsin is extremely sensitive to light, and thus enables vision in low-light conditions rhodopsin is found in roads Answer : (d)

Na+-K+ pump uses ATP as energy source Primary active transport directly uses a source of chemical energy (e.g., ATP) to move molecules across a membrane against their gradient Answer : (c)

In a neuron, synaptic vesicles (or neurotransmitter vesicles) store various neurotransmitters that are released at the synapse. A presynaptic neuron is a nerve cell that releases chemical messengers called neurotransmitters into the synapse. Anatomically, the presynaptic neuron is the neuron before the synapse, this neuron is delivering the "message" across the synapse to the postsynaptic neuron. The postsynaptic neuronis the "receiver" of the neurotransmitter "message". synaptic cleft called also synaptic gap. the spacebetween neurons at a nerve synapse across which a nerve impulse is transmitted by a neurotransmitter. Answer : (a)

Cobra, mamba, and coralsnakes, their venom is neurotoxic (nerve toxins) and paralyses the respiratory centre. Viperine venom is typically haemotoxic (blood toxins), necrotising (death of tissue), and anticoagulant (preventing the blood from clotting) Answer : (b)

two fluid-filled sacs forming part of the labyrinth of the inner ear (the other being the utriculus). Three semicircular ducts and two chambers, which contain the saccule and utricle, enable the body to detect any deviation from equilibrium and maintain static equilibrium. Answer: (d)

Rhodopsin (also known as visual purple) is a light-sensitive receptor protein involved in visual phototransduction. Answer : (b)

Refractory period – period of time, after neuron has generated an action potential, when neuron cannot be stimulated to generate another action potential Answer : (a)

Rejection is unusual after corneal transplantation because the cornea usually does not have blood vessels. Without blood vessels the body's immune system is less likely to recognise and reject the “foreign” graft. The cornea in patients with keratoconus does not usually have blood vessels. Answer : (b)

Calcium ions trigger the release of neurotransmitter from synaptic vesicles into the synaptic cleft Answer : (d)

There are three types of cone cells and each type has a different sensitivity to light wavelengths. One type of cone perceives blue light, another perceives green and the third perceives red. Severe color blindness occurs when all three conecells are absent. Mild color blindness happens when all three cone cells are present but one cone cell does not work right Answer : (a)

When we move from dark to light, we fail to see for some time but soon the visibility becomes normal. It is Adaptation. A minor mechanism of adaptation is the pupillary light reflex, adjusting the amount of light that reaches the retina. In response to varying ambient light levels, rods and cones of eye function both in isolation and in tandem to adjust the visual system. Answer : (b)

The three main components of the central nervous system are the brain, spinal cord and neurons Answer : (c)

The meibomian glands, located in the tarsal plate of the rabbit eyelid, are sebaceous (oil-secreting) glands. Its secretions help lubricate the eyelids. Answer : (a)

Cranial Nerve	Name	Function
I	The Olfactory Nerve	Sense of Smell
II	The Optic Nerve	Vision
III	The Oculomotor Nerve	Raise eyelids, move eyes, regulate the size of pupils, focus of lenses.
IV	The Trochlear Nerve	Eye movements, proprioception
V	The Trigeminal Nerve	Sensations of the head and face, chewing movements, and muscle sense.
VI	The Abducent Nerve	Produce movements of the eyes
VII	The Facial Nerve	Facial expressions, secretion of saliva, taste.
VIII	The Vestibulocochlear Nerve	Balance or equilibrium sense. Hearing.
IX	The Glossopharyngeal Nerve	Taste and other sensations of tongue, swallowing, secretion of saliva, aid in reflex control of blood pressure and respiration.
X	The Vagus Nervehistorically cited as the pneumogastric nerve	Transmit impulses to muscles associated with speech, swallowing, the heart, smooth muscles of visceral organs in the thorax, and abdomen.
XI	Accessory nerve	Turning movements of the head, movements of the shoulder and viscera, voice production.
XII	Hypoglossal	Tongue movements

Answer : (c)

The autonomic nervous system (ANS) controls functions of the internal viscera, blood vessels throughout the body, effectors in the skin and glands, in fact all organs except voluntarily controlled striated muscle. Answer : (b)

When a reflex arc consists of only two neurons in an animal (one sensory neuron, and one motor neuron), it is defined as monosynaptic. Answer : (b)

(a) Ganglionic cells (b) Bipolar neurons (c) Photosensory cells (d) Pigment epithelium Answer : (c)

the ectoderm differentiates to form the nervous system spine, peripheral nerves and brain Answer : (d)

Organ of Corti is composed of mechanosensory cells, known as hair cells, positioned on the basilar membrane of the organ of Corti are three rows of outer hair cells (OHCs) and one row of inner hair cells (IHCs). Separating these hair cells are supporting cells: Deiters cells, also called phalangeal cells Answer : (b)

The fourth ventricle has a characteristic diamond shape in cross-sections of the human brain. It is located within the pons or in the upper part of the medulla. CSF entering the fourth ventricle through the cerebral aqueduct can exit to the subarachnoid space of the spinal cord through two lateral apertures and a single, midline median aperture. Answer : (a)

The hormones from the hypothalamus govern physiologic functions such as temperature regulation, thirst, hunger, sleep, mood, sex drive, and the release of other hormones within the body. Answer : (c)

Farsightedness or hyperopia, is caused when the curvature of the cornea is too flat, or the eyeball is too short, forcing light to focus behind the retina. Farsightedness (hyperopia) is a common vision condition in which you can see distant objects clearly, but objects nearby may be blurry. The degree of your farsightedness influences your focusing ability. Answer : (a)

Oligodendrocytes are neuroglial cells which produce myelin sheath in central nervous system while Schwann cell produces myelin sheath in peripheral nervous system. Answer:(a)

Cutaneous Plexus: .network of arteries that forms in the subcutaneous tissue and along the reticular layer of the dermis. Papillary plexus: branching network covers the blood supply from the papillary layer of the dermis into the epidermis Answer : (a)

Glaucoma is a condition that causes damage to eye's optic nerve and gets worse over time. It's often linked to a buildup of pressure inside eye. Answer : (d)

auditory capsule the bony or cartilaginous capsule that encloses the middle and inner parts of the ear. A small natural hole or opening, especially in a bone. The mammalian middle ear is linked by the fenestra ovalis to the vestibule of the inner ear, and by the fenestra rotunda to the cochlea. Answer : (c)

Excessive stimulation of vagus nerve causes stimulation of the superior and recurrent laryngeal nerves and is associated with problems ranging from alteration of voice (66%), coughing (45%), pharyngitis (35%) and throat pain (28%) and hoarseness (very common) to frank laryngeal muscle spasm and upper airway obstruction. Answer : (a)

Answer : (d)

In figure Na-K pump shown in red is pumping Na+ out of cell and pumping K+ in cell Duringdepolarisation Na-K pump, pumping three positively charged sodium ions (Na+) out of the cell for every two positively charged potassium ions (K+) pumped into the cell, Answer : (c)

Answer : (a)