Quiz 8: The Nervous System

Biology

In conjunction with the endocrine system, the nervous system controls other organ systems of the body, such as the cardiovascular and respiratory systems. The nervous system is the most complex of all organ systems present in the body. It is composed of two major anatomical divisions. They are central nervous system (CNS) and peripheral nervous system (PNS). The CNS comprises of the brain and spinal cord. The brain coordinates higher functioning, such as memory and critical thinking. It also interprets stimuli and controls motor movement. It communicates with the rest of the body through the peripheral nervous system. The PNS embodies all the nervous tissue outside of the CNS. Stimuli travel through the peripheral nervous system to the brain in the CNS for processing. The brain responds by sending actions to the body back through the PNS.

Neuroglia are specialized non-neuronal nervous tissue in the central and peripheral nervous system. They are supporting cells of neurons in the nervous system. Thus, the correct answer is f. There are four neuroglial cells in the central nervous system (CNS). These include the astrocytes, oligodendrocytes, microglia, and ependymal cells. An astrocyte is the largest and most numerous neuroglial cell. They are vital in protecting the central nervous system. They secrete chemicals that act on blood vessels in the CNS. These secretions limit the permeability of the capillaries in the CNS to molecules that could potentially damage the brain and spinal cord. This is the basis for the blood-brain-barrier. Astrocytes also provide a structural framework for the CNS and repair damaged tissue. Oligodendrocytes have a thin membrane called myelin that wraps around the axons of neurons. An axon is covered in myelin and punctuated with short breaks called nodes of Ranvier. Myelin insulates electrical impulses to increase their speed of transmission. Microglia are the smallest and least numerous of the central nervous system neuroglia. They are immune system cells derived from white blood cells. They are phagocytic and protect the CNS by engulfing pathogens and cellular waste. Ependymal cells line the cavities within the central nervous system. These cavities are filled with cerebrospinal fluid (CSF) and include the ventricles in the brain and the central canal of the spinal cord. Ependymal cells produce some of the CSF and help move it through the CNS cavities through the wavelike motion of cilia.

The nervous system controls all the other organ systems of the body, such as the cardiovascular and respiratory systems. The nervous system is the most complex of all organ systems present in the body. It is composed of two major anatomical divisions. They are central nervous system (CNS) and peripheral nervous system (PNS). The CNS consists of the brain and spinal cord. The brain coordinates higher functioning, such as memory and critical thinking. It also interprets stimuli and controls motor movement. It communicates with the rest of the body through the peripheral nervous system. The PNS embodies all the nervous tissue outside of the CNS. The PNS is composed of two functional divisions - the afferent and efferent divisions. The afferent division of the PNS relays sensory information from outside the nervous system to the CNS for processing. Somatic receptors monitor conditions outside our body. Visceral receptors monitor internal conditions. The brain responds to stimuli and sends commands back to the body through the efferent division of the PNS. The efferent division is further divided into voluntary and involuntary control pathways.

There is no answer for this question

There is no answer for this question