Our ear can hear sound waves of frequency between 20-20000 cycles/sec Answer : (b)

Grey matter is distributed at the surface of the cerebral hemispheres (cerebral cortex) and of the cerebellum (cerebellar cortex), as well as in the depths of the cerebrum Answer : (a)

cerebrum or cortex is the largest part of the human brain, associated with higher brainfunction such as thought and action. a. – s Cerebellum Maintains body posture b. – t Hypothalamus Controls pituitary.c. – p. The midbrain serves important functions in motor movement, particularly movements of the eye, and in auditory and visual processing. d. – q Answer : (d)

An axon has four terminal ends connected with dendrites of four different neurons. Its nerve impulse will travel in all the four neurons with equal strength Answer : (b)

Neurosecretory cell occur in Hypothalamus. The cells typically have two or three long dendrites, which also contain large dilations and a very high density of hormone-containing vesicles. Oxytocin and vasopressin can, thus, be released within the brain from these dendrites, as well as into the blood from the terminals in the posterior pituitary gland. Answer : (a)

Abducens: It controls the eye's lateral rectus muscle, which moves the eye sideways, away from the nose. Answer : (b)

The natural blind spot (scotoma) is due to lack of receptors (rods or cones) where the optic nerve and blood vessels leave the eye. Answer : (b)

The occipital lobe makes sense of visual information so that we are able to understand it. If our occipital lobe was impaired, or injured we would not be able to correctly process visual signals, thus visual confusion would result. Answer : (a)

When an impulse is sent out from a cell body, the sodium channels open and the positive sodium cells surge into the cell. Once the cell reaches a certain threshold, an action potential will fire, sending the electrical signal down the axon Answer : (c)

Ganglia:is a nerve cell cluster or a group of nerve cell. Lateral funiculus: large bundle of nerve tracts that make up the white matter of the spinal cord. Answer : (d)

Energy required for movement of Na+/K+ during nerve conduction is from ATP. This movement produce electric potential. Thus energy transformation is chemical to electrical Answer : (c)

The limbic system, is responsible for our emotional lives, many higher mental functions such as learning and formation of memories. The primary structures within the limbic system include the amygdala, hippocampus, thalamus, hypothalamus, basal ganglia, and cingulate gyrus. Answer : (b)

Dorsal root of spinal nerve: transmit information of discriminative touch, pressure, vibration, and conscious carry pain and temperature sensation Answer : (a)

Homeostasis refers to the ability of the body or a cell to seek and maintain a condition of equilibrium or stability within its internal environment when dealing with external changes. It is involved in the maintenance of the constant internal environment which includes the function of kidney, liver, skin, etc. Diencephalon consists of structures that are lateral to the third ventricle, and includes the thalamus, the hypothalamus, the epithalamus and the subthalamus. hypothalamus is to link the nervous system to the endocrine system via the pituitary gland (hypophysis). Which secrete hormone to regulate various other glands and organs Answer : (c)

Answer : (d)

The utricle contains mechanoreceptors called hair cells that distinguish between degrees of tilting of the head. Sacculus: It contains a region of hair cells and otoliths which send signals to the brain concerning the orientation of the head. Semicircular canals: canal is filled with a fluid called endolymph and contains motion sensors within the fluids. Answer : (b)

Paracoel or lateral ventricles I and II are present inside the cerebral hemispheres. The diencephalon has ventricle III. Ventricle III is in connection with lateral ventricles by foramen of Monro. Answer : (a)

Second cranial nerve: carrying impulses for the sense of sight. It originates in the lateral geniculate body of the thalamus and travels by the optic tract and optic chiasma, where it enters the retina through the optic disk. Answer : (d)

Answer : (b)

Dorsal nerve roots control the sensation of temperature and pain, so mammal won’t show response to stimulation of receptor in skin Answer : (b)

Iris: is the barrier between the front and back of the eye. Each iris has a muscle running through it that constricts and dilates to allow the right amount of light to enter the eye at any given time. The sphincter muscle lies around the edge of the pupil. In bright light, this muscle contracts, allowing only a small amount of light to get it. In dim light, the sphincter muscle dilates, letting in as much light as possible. Answer : (d)

The nervous system consists of the brain, spinal cord, sensory organs, and all of the nerves that connect these organs with the rest of the body. Together, these organs are responsible for the control of the body and communication among its parts Answer : (c)

Synapses: Nerve impulse conduction is always unidirectional Chemical synapses are unidirectional Ensure one way transmission of nerve impulse Answer : (a)

The Resting Membrane Potential is always negative (-70mV) Answer : (b)

Frontal lobe Function: Controlling Movement, Problem-Solving and Decision-Making, Maintaining Interpersonal Relationship, Control Over Emotions and Behavior Answer : (a)

Macula lutea: An oval yellowish area surrounding the fovea near the centre of the retina in the eye. Answer : (c)

Reflex arc the circuit traveled by impulses producing a reflex action: receptor organ, afferent nerve, nerve center, efferent nerve, effecter organ in a muscle Answer : (a)

Pia mater functions to cover and protect the central nervous system, to protect the blood vessels and enclose the venous sinuses near the CNS, to contain the cerebrospinal fluid and to form partitions with the skull. Answer : (c)

anesthetics block nerve conduction by preventing the increase in membrane permeability to sodium ions that normally leads to a nerve impulse. Among anesthetics containing tertiary amine groups, the cationic, protonated form appears to be more active than the neutral form. Answer : (d)

Answer : (b)

Frontal lobe Function: Controlling Movement, Problem-Solving and Decision-Making, Maintaining Interpersonal Relationship, Control Over Emotions and Behavior Answer : (a)

Paracoel or lateral ventricles I and II are present inside the cerebral hemispheres. The diencephalon has ventricle III. Ventricle III is in connection with lateral ventricles by foramen of Monro Answer : (c)

All options are part of homeostasis Homeostasis refers to the ability of the body or a cell to seek and maintain a condition of equilibrium or stability within its internal environment Hypothalamus : secrete hormone to regulate various other glands and organs there by regulate equilibrium in the organism Answer : (d)

Cone cells, or cones, are one of two types of photoreceptor cells in the retina of the eye. They are responsible for color vision and function best in relatively bright light, as opposed to rod cells, which work better in dim light. Answer : (b)

Synaptic vesicle: membrane-bound vesicles at a synaptic junction of neurons that contain the neurotransmitter. Presynaptic neuron: a neuron from the axon terminal of which an electrical impulse is transmitted across a synaptic cleft to the cell body or one or more dendrites of a postsynaptic neuron by the release of a chemical neurotransmitter Answer : (a)

The corpus callosum is only found in placental mammals. The cerebrum is divided into two cerebral hemispheres connected by a mass of white matter known as the corpus callosum Answer : (c)

The cerebrum is a major part of the brain, controlling emotions, hearing, vision, personality and much more. It controls all voluntary actions. Answer : (d)

When the sound waves are transmitted from the eardrum to the oval window, the middle ear is functioning as an acoustic transformer amplifying the sound waves before they move on into the inner ear. The pressure of the sound waves on the oval window is some 20 times higher than on the eardrum. Answer : (c)

Adrenaline: hormone secreted by the adrenal glands that increases rates of blood circulation, breathing, and carbohydrate metabolism and prepares muscles for exertion. Also called epinephrine. SA node is the pacemaker for the heart, but it in turn is controlled by the vagus nerve Answer : (c)

c)Parkinson's disease is a progressive disorder of the nervous system that affects movement. Bradykinesia: Slow movement. impaired ability to adjust the body's position. Akinesia:Absence or loss of the power of voluntary movement Tremor can be a symptom associated with disorders control muscles as the hands. a)Epilepsy: is a brain disorder that causes people to have recurring seizures. The seizures happen when clusters of nerve cells, or neurons, in the brain send out the wrong signals. b) Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills, and eventually the ability to carry out the simplest tasks. c) Huntington’s disease is a hereditary condition in which your brain’s nerve cells gradually break down. This affects your physical movements, emotions, and cognitive abilities. Answer : (c)

All ethanol contained in alcoholic beverages is produced by means of fermentation induced by yeast. Saccharomyces is a genus of fungi that includes many species of yeasts. Many members of this genus are considered very important in food production. It is known as the brewer's yeast or baker's yeast. Answer : (a)

Net yield of ATP per step in aerobic respiration: Glycolysis: 2ATP / glucose. Krebs Cycle: 2ATP/glucose. Electron Transport Chain (oxidative phosphorylation): 32 ATP/glucose. Total: 36 ATP/glucose (for eukaryotic cells) Answer : (b)

In the first step of the Krebs cycle, acetyl CoA joins with a four-carbon molecule, oxaloacetate(OAA), releasing the COA group and forming a six-carbon molecule called citrate. Answer : (a)

An electron acceptor is a chemical entity that accepts electrons transferred to it from another compound. It is an oxidizing agent that, by virtue of its accepting electrons, is itself reduced in the process. Organic acids such as pyruvate and malate produced in the cytosol by processes described above are further oxidised in mitochondria by the tricarboxylic acid (TCA) cycle and subsequent respiratory chain. Energy released by this oxidation is used to synthesise ATP which is then exported to the cytosol for use in biosynthesis and growth. ETC and TCA enzyme occur in motochondria Answer : (c)

Respiratory quotient is the ratio of the volume of carbon dioxide produced to the volume of oxygen consumed in respiration over a period of time. RQ = Volume of CO2 evolved/Volume of O2 absorbed C4H6O + 3O2 → 4CO2 + 3HO2O RQ = 4CO2/3O2 or 1.3 malic acid Answer : (a)

Biology textbooks often state that 38 ATP molecules can be made per oxidized glucose molecule during cellular respiration (2 from glycolysis, 2 from the Krebs cycle, and about 34 from the electron transport system). Answer : (b)

Pyruvicacid Chemical formula: C3H4O3 Answer : (b)

Oxidative phosphorylation (or OXPHOS in short) is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing energy which is used to reform ATP. Answer : (c)

Foramen of Monro : the small opening (on both the right and left sides) that connects the third ventricle in the diencephalon with the lateral ventricle in the cerebral hemisphere Answer : (b)

GABA is an inhibitory neurotransmitter It plays the principal role in reducing neuronal excitability throughout the nervous system. In humans, GABA is also directly responsible for the regulation of degree of muscle tension or resistance during rest or in response to stretching. Answer : (a)