Which one of the endocrine glands is known as master gland ?
Pituitary gland is called master gland because it controls the secretion of all other endocrine glands.
Cerebral hemispheres are the centres of :-
The cerebrum, the large, outer part of the brain, controls reading, thinking, learning, speech, emotions and planned muscle movements like walking. It also controls vision, hearing and other senses. The cerebrum is divided two cerebral hemispheres (halves): left and right.
The cerebellum is concerned with :-
The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity.
Learning (intelligence) is related to :-
It functions as the center of sensory perception, memory, thoughts and judgement; the cerebrum also functions as the center of voluntary motor activities.
Junction of two neurons is called :-
Synapse is a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.
The reflex arc in the reflex action is formed by :-
Olfactoreceptors help to respond to :-
Olfactory means related to smell hence olfactor receptors help to respond to smell.
Brain is a part of :-
The central nervous system (CNS) controls most functions of the body and mind. It consists of two parts: the brain and the spinal cord.
The brain is the center of our thoughts, the interpreter of our external environment, and the origin of control over body movement. Like a central computer, it interprets information from our eyes (sight), ears (sound), nose (smell), tongue (taste), and skin (touch), as well as from internal organs such as the stomach.
Cerebrum is a part of :-
The cerebrum is a large part of the brain containing the cerebral cortex (of the two cerebral hemispheres), as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb. In the human brain, the cerebrum is the uppermost region of the central nervous system. The prosencephalon is the embryonic structure from which the cerebrum develops prenatally.
The neurons that carry nerve impulse from spinal cord to effectors are called :-
Motor Neurons- Motor neurons carry impulses from the CNS to effector organs Motor neurons are also called efferent neurons. The cell bodies of motor neurons are inside the CNS.
Chemical transmission of nerve impulses from one neuron to another at a synapse is by :-
The distal end of the axon terminals have swollen ends to form “ bulbs” which store chemicals called neurotransmitters. These are responsible for passing the impulse from one neuron to another or from a neuron to a tissue. (Acetylcholine is an important neurotransmitter.)
"Nodes of Ranvier" are found in :-
Nodes of Ranvier are microscopic gaps found within myelinated axons. Their function is to speed up propagation of action potentials along the axon via saltatory conduction. The Nodes of Ranvier are the gaps between the myelin insulation of Schwann cells which insulate the axon of neuron.
Afferent nerve fiber conducts impulse from :-
Afferent neurons carry signals towards the CNS – afferent means “towards”. They provide information about the external environment and the regulatory functions being carried out by the nervous system.
An afferent neuron has a receptor at its ending that generates action potentials in response to a particular stimulus. These action potentials are transmitted along the length of the axon towards the spinal cord (which is part of the CNS).
Saltatory conduction occurs in :-
Myelinated axons only allow action potentials to occur at the unmyelinated nodes of Ranvier that occur between the myelinated internodes. It is by this restriction that saltatory conduction propagates an action potential along the axon of a neuron at rates significantly higher than would be possible without the myelination of the axon (150 m/s compared to 0.5 to 10 m/s). As sodium rushes into the node it creates an electrical force which pushes on the ions already inside the axon.
Power of regeneration is lowest in :-
Brain cells stay within the starting stage of interphase of cell copy for his or her life, and ne'er divide, and instead develop by forming new synapses with different neurons. They lack cellular machinery for organic process.
The Schwann sheath is :-
Schwann cells are a variety of glial cells that keep peripheral nerve fibres (both myelinated and unmyelinated) alive. In myelinated axons, Schwann cells form the myelin sheath. The sheath is not continuous. During peripheral nerve regeneration, 9-O-acetyl GD3 is expressed by Schwann cells.
Non Myelinated axons differ from myelinated in that they :-
Myelinated and unmyelinated nerve fibers are the two forms of nerve fibers that are found in the nervous system. The main difference between myelinated and unmyelinated nerve fibers is that myelinated nerve fibers contain a myelin insulation whereas unmyelinated nerve fibers do not contain a myeline insulation.
Which is the longest part of the neuron?
The longest part of a motor neuron is the axon. The axon is an extension that comes out of the cell body and travels long distances to reach a muscle or gland. Axons allow electrical signals to travel long distances quickly and deliver action potentials to trigger for example the muscular contraction.
Corpus callosum connects :-
The basal ganglia is found in the white matter. The cerebrum is divided in to left and right hemispheres. The left half controls the right side of the body and the right half controls the left side of the body. A mass of nerve fibers known as the corpus callosum connects the two hemispheres and allows communication between the two. The surface of the cerebrum is made up of gyri and sulci.
Cerebellum is concerned with :-
Coordination of Movement-the cerebellum controls the timing and pattern of muscle activation during movement.
How many lobes are present in cerebellum :-
There are three anatomical lobes that can be distinguished in the cerebellum; the anterior lobe, the posterior lobe and the flocculonodular lobe. These lobes are divided by two fissures – the primary fissure and posterolateral fissure.
The box like bony structure which encloses the brain is called :-
The box enclosing and protecting the brain is called as the cranium. The cranium is the part of the skull, that encloses the brain. It is sometimes called as the braincase.
The function of cerebrospinal fluid surrounding CNS is to :-
Largest cavity in brain is called :-
The four cavities of the human brain are called as ventricles. The two largest are the lateral ventricles in the cerebrum. These first and second ventricles present in two cerebral hemispheres is called as the paracoel.
Voluntary activites of body are controlled by :-
Voluntary actions are controlled by the cerebellum and involve such activities as standing up from a seat, raising your hand and throwing a kick.