Fundamentals Of The Nervous System

The given answer is "unipolar" because it states that there is only one process extending from the cell body, which is a characteristic of unipolar neurons. Unipolar neurons are typically found in the peripheral nervous system (PNS) and are commonly sensory neurons that transmit information from sensory receptors to the central nervous system.

The statement accurately describes the physiological responses of the sympathetic nervous system, which is responsible for the "fight or flight" response. When activated, the sympathetic nervous system increases heart rate, blood pressure, respiratory rate, and causes dilation of the pupils and sweating. Therefore, the answer "True" is correct.

Nerves are indeed processes of motor and/or sensory neurons that are arranged into bundles. Nerves are responsible for transmitting signals between different parts of the body and the central nervous system. These bundles of nerve fibers allow for the efficient and coordinated communication between the brain, spinal cord, and the rest of the body. Therefore, the statement "Nerves are processes of motor and/or sensory neurons (nerve fibers arranged into bundles)" is true.

The autonomic nervous system is responsible for controlling involuntary bodily functions, such as heart rate, digestion, and breathing. Unlike the somatic nervous system, which controls voluntary movements, the autonomic nervous system operates without conscious control. Therefore, the correct answer is "involuntary."

Dopamine and norepinephrine are indeed natural hormones found in the body that are associated with making your body feel good. Dopamine is often referred to as the "feel-good" hormone as it plays a role in pleasure, motivation, and reward. Norepinephrine is involved in the body's stress response and helps regulate mood. Both hormones are important for overall well-being and can contribute to feelings of happiness and satisfaction. Therefore, the statement "Dopamine and norepinephrine are natural hormones found in the body that are associated with making your body feel good" is true.

The parasympathetic nervous system is responsible for slowing down physiological processes in the body, including heart rate, respiratory rate, and sweating. It works in opposition to the sympathetic nervous system, which is responsible for activating these processes. Therefore, the statement that the parasympathetic reverses the sympathetic and slows down heart rate, respiratory rate, and sweating is true.

Neurons are specialized cells that carry impulses, allowing communication within the nervous system. Unlike most cells, neurons do not typically divide. They are responsible for transmitting electrical signals and information throughout the body, enabling various functions such as movement, sensation, and cognition. Neurons are crucial for the proper functioning of the nervous system and play a vital role in coordinating and regulating bodily activities.

The given statement is true because neurons are indeed long-lived cells that cannot reproduce themselves. They have a high metabolic activity, which is necessary for their functioning. Additionally, neurons are highly dependent on oxygen and cannot survive for more than about 7 minutes without it.

The correct answer is sensory because the statement mentions "Impulses from receptors in skin, sense organs, and viscera to the brain and spinal cord." This indicates that the information being transmitted is related to sensory input from various parts of the body to the central nervous system.

Action potentials are electrical impulses that allow communication between neurons. These signals are generated in the axon of a neuron and are capable of traveling long distances along the axon. This is possible due to the presence of voltage-gated ion channels that open and close, allowing the propagation of the action potential. As a result, action potentials can transmit information over long distances, enabling communication between different regions of the nervous system. Short distance signals, on the other hand, are typically mediated by graded potentials that do not have the ability to travel far.

The correct answer is electrical and chemical. Synapses are the junctions between two neurons where information is transmitted. Electrical synapses allow for direct communication between neurons through the flow of ions, while chemical synapses involve the release and binding of neurotransmitters to transmit signals. Solvents and acids are not types of synapses, so they are not the correct answers.

The given correct answer is "parallel processing." This is because the explanation states that input travels along several different pathways to be integrated in different CNS regions. This suggests that multiple processes are happening simultaneously, or in parallel, rather than one after the other, which would be serial processing.

Oligodendrocytes are cells in the central nervous system that provide support to neurons by forming protective rows between them. They also produce myelin sheaths, which are insulating coverings around the endings of neurons. This helps in the efficient transmission of electrical signals in the brain and spinal cord.

The given answer "motor" correctly describes the impulses from the brain and spinal cord to effectors, which can be either muscles or glands. These impulses are responsible for initiating and controlling movement and bodily functions. The other terms mentioned, "sensory" and "association," are not relevant to this specific function of transmitting impulses from the central nervous system to effectors.

BBB refers to the blood-brain barrier, a protective barrier that prevents harmful substances from entering the brain. In infants, the BBB is not fully developed, making them more vulnerable to brain disorders as harmful substances can easily cross into the brain. Therefore, the statement that BBB is poorly developed in infants and has the potential for damage of brain disorders is true.

Repolarization refers to the process of restoring the normal electrical charges in a cell. In this context, it specifically involves the return to the resting membrane potential after depolarization, where the inside of the cell becomes negatively charged compared to the outside. Therefore, repolarization is the correct answer as it accurately describes the phenomenon of returning to the normal electrical charges, with positive charges outside the cell and negative charges inside.

Impairment of impulse conduction can be caused by various factors such as alcohol, sedatives, anesthesia, cold temperature, etc. These substances and conditions can affect the normal functioning of the nervous system, leading to a decrease in the speed or efficiency of impulse transmission. Therefore, all of the options listed above can impair the conduction of impulses.

A synapse is indeed a connection. In the context of neuroscience, a synapse refers to the junction between two neurons, where electrical or chemical signals are transmitted. This connection allows for communication and information processing within the nervous system. Therefore, the statement "A synapse is a connection" is correct.

Dendrites are highly branched extensions of a neuron's cell body that carry impulses towards the cell body. They also serve as receptor sites for impulses from other neurons. This means that dendrites receive incoming signals from other neurons and transmit them towards the cell body, allowing for communication and integration of information within the nervous system.

When a neuron receives an electrical impulse that travels along its axon, it is known as an action potential. This is the term used to describe the electrical signal that is generated and transmitted by neurons to communicate with other cells in the body. The action potential plays a crucial role in the transmission of information within the nervous system, allowing for the coordination of various bodily functions and behaviors.

The somatic nervous system involves voluntary actions. This system is responsible for controlling voluntary movements and sensory information. It includes the nerves that control skeletal muscles and allows us to consciously control our actions. In contrast, the involuntary nervous system, also known as the autonomic nervous system, controls involuntary actions such as heart rate, digestion, and breathing.

Schwann cells are similar to oligodendrocytes in their function of providing support and insulation to neurons. However, unlike oligodendrocytes which are found in the central nervous system (CNS), Schwann cells are specifically found in the peripheral nervous system (PNS). Therefore, the correct answer is Schwann.

Graded potentials are changes in the membrane potential that can either depolarize or hyperpolarize a neuron. These signals occur in response to stimuli and can vary in magnitude. Graded potentials are typically local, meaning they only spread over short distances within the neuron. They are important for initiating action potentials, which are the long-distance signals that allow for communication between neurons. Therefore, the correct answer is short distance signals.

An electrical synapse is a membrane that does touch. Electrical synapses are specialized connections between neurons where the membranes of the cells are physically close together, allowing for direct electrical communication. This direct contact allows for the rapid transmission of signals between neurons, without the need for chemical neurotransmitters. These synapses are important for the synchronization of activity between neurons and play a role in various physiological processes such as the coordination of movement and the transmission of sensory information.

The two divisions of the peripheral nervous system are the somatic nervous system and the autonomic nervous system. The somatic nervous system controls voluntary movements and sensory information, while the autonomic nervous system regulates involuntary processes such as heart rate, digestion, and breathing.

Histology is the study of tissues. Tissues are groups of similar cells that work together to perform a specific function in the body. Histologists use microscopes to examine the structure and composition of tissues, which helps in understanding the organization and function of different organs. By studying tissues, histologists can gain insights into various diseases and conditions, as well as develop new treatments and therapies.

The correct answer is axon. An axon is a single extension of a cell body that carries impulses away from the cell body. It also forms junctions with other structures including muscles, glands, and other neurons. Additionally, an axon can be up to 3 ft in length.

Schwann cells are responsible for the development of the myelin sheath. The myelin sheath is a protective covering that surrounds nerve fibers, allowing for faster and more efficient transmission of electrical signals. Schwann cells wrap around the nerve fibers, forming multiple layers of myelin that insulate and protect the fibers. This insulation helps to prevent signal loss and ensures that the electrical impulses can travel smoothly along the nerve fibers.

Hyperpolarization refers to a change in the electrical potential across a cell membrane, causing it to become more negative. This makes it less likely for nerve impulses to occur because it increases the threshold required to reach the action potential. Therefore, hyperpolarization decreases the probability of producing nerve impulses.

The structure of a neuron consists of several components. The cell body, also known as the soma, contains the nucleus and other organelles. Neuron processes, such as dendrites and axons, extend from the cell body to transmit signals. Nerve fibers refer to the long, thread-like extensions of neurons that carry information. The myelin sheath is a protective covering around nerve fibers, formed by Schwann cells in the peripheral nervous system. The neurilemma is the outermost layer of the Schwann cell. Therefore, the correct answer is "all of the above" as it includes all the mentioned components of a neuron's structure.

The given correct answer is "multipolar." This means that the neuron has several dendrites and one axon. In the brain and spinal cord, 99% of neurons are multipolar and they are mostly association neurons. This type of neuron is responsible for connecting different areas of the brain and spinal cord, allowing for complex communication and integration of information.

The correct answer is conduction velocity. The explanation provided states that the presence of a myelin sheath and a large diameter of the nerve result in faster conduction velocity, while the absence of a myelin sheath leads to slower conduction velocity. This suggests that the conduction velocity of a nerve signal is influenced by factors such as the size of the nerve and the presence of myelin.

The sensory division is not a function of the nervous system. The nervous system is responsible for sensory input, motor output, and interpreting changes, integrating information, and making decisions. The sensory division refers to the part of the peripheral nervous system that transmits sensory information from the sensory organs to the central nervous system.

Ependymal cells are a type of epithelial cells that line the ventricles of the brain and the central canal of the spinal cord. These cells are actively involved in the production of cerebrospinal fluid, which helps cushion and protect the brain and spinal cord. The cilia on the surface of ependymal cells help circulate the cerebrospinal fluid, ensuring its proper distribution throughout the central nervous system.

Astrocytes are star-shaped cells that make up half the volume of the brain and are responsible for creating the blood-brain barrier (BBB). The BBB is a structure formed by weblike projections from the relatively tight junctions around the brain's capillaries. This barrier is designed to protect the brain from harmful substances and maintain a stable environment for proper brain function. Therefore, astrocytes play a crucial role in maintaining the integrity and functionality of the brain by forming the BBB.

Calcium enters from the surrounding extracellular fluid when information reaches the end of an axon. Calcium ions play a crucial role in the process of neurotransmitter release at the synapse. When an action potential reaches the axon terminal, voltage-gated calcium channels open, allowing calcium ions to enter the axon terminal. This influx of calcium triggers the release of neurotransmitters from vesicles into the synaptic cleft, enabling communication between neurons.

The BBB, or blood-brain barrier, is a protective mechanism that prevents certain substances from entering the brain. While this barrier is essential for maintaining brain health, it can also hinder the effectiveness of chemotherapy drugs in treating brain tumors. The BBB acts as a defense mechanism, preventing chemotherapy drugs from reaching the tumor cells and reducing their efficacy. Therefore, it is true that the BBB actually protects brain tumors from chemotherapy.

Depolarization is the reversal of charge that occurs during an action potential. It is a process where the inside of the cell becomes more positive compared to the outside, allowing the nerve impulse to propagate along the neuron. If the depolarization is too weak, meaning that the reversal of charge is not significant enough, an action potential will not occur.

The resting membrane potential refers to the electrical charge difference across the cell membrane when the cell is at rest. In this state, the inside of the cell is negatively charged compared to the outside. The correct answer, "Positive external and negative internal," accurately describes the resting membrane potential by indicating that the external environment has a positive charge while the internal environment has a negative charge.

Neurons, also known as nerve cells, are responsible for the function of impulse conduction. These cells are typically large in size and play a crucial role in transmitting electrical signals throughout the body. Neurons consist of various structures including axons, which are long, slender projections that transmit signals away from the cell body. Schwann cells, on the other hand, are a type of glial cell that support and protect the axons. Therefore, the correct answer for this question is "Neurons."

Serial processing is the correct answer because it refers to a sequential flow of information in which one neuron stimulates another, which then stimulates another, and so on. This linear progression suggests that each neuron in the neural network is activated in a specific order, leading to a step-by-step processing of information. In contrast, parallel processing involves multiple neurons processing information simultaneously, without a strict linear sequence. Therefore, serial processing accurately describes the linear nature of the neural process described in the question.

The correct answer is BBB, Blood Brain Barrier. The blood-brain barrier is a highly selective semipermeable barrier that separates the circulating blood from the brain extracellular fluid in the central nervous system. It is formed by specialized endothelial cells lining the capillaries in the brain, along with astrocytes and other supporting cells. The blood-brain barrier plays a crucial role in maintaining the stability of the brain's chemical environment by selectively allowing certain molecules to pass through while blocking others based on their size and chemical makeup. This helps protect the brain from fluctuations in chemical compounds that may be present in other areas of the body.

The central nervous system is classified into two groups: the peripheral nervous system and the central nervous system. The peripheral nervous system consists of the nerves and ganglia outside of the brain and spinal cord, while the central nervous system includes the brain and spinal cord.

Association neurons, also known as interneurons, are responsible for transmitting impulses between sensory neurons and motor neurons. They are located in the brain and spinal cord, making up approximately 99% of all neurons in the body. These neurons play a crucial role in processing and integrating sensory information, allowing for complex cognitive functions and coordinated motor responses.

Microglia are a type of modified white blood cells found in the brain. They are usually stationary but can migrate to the site of injury and engulf bacteria. They are also known as brain macrophages. This explanation describes the characteristics and functions of microglia, providing a clear understanding of why they are the correct answer.

The correct answer is Multiple Sclerosis. Multiple Sclerosis is a disease that affects the central nervous system, specifically the brain and spinal cord. It is characterized by the destruction of myelin, the protective covering of nerve fibers, leading to communication problems between the brain and the rest of the body. This highlights the importance of myelin, as its damage in Multiple Sclerosis results in various neurological symptoms such as muscle weakness, coordination difficulties, and cognitive impairments. Muscular dystrophy, on the other hand, is a group of genetic disorders that primarily affect the muscles, not the myelin. Therefore, the correct answer is Multiple Sclerosis.

Most antibiotics/medications, urea, and certain toxins cannot pass through the blood-brain barrier (BBB). The BBB is a protective barrier that separates the bloodstream from the brain tissue, and it selectively allows certain substances to pass through while blocking others. Glucose, oxygen, essential amino acids, and some electrolytes can pass through the BBB, but various fat-soluble molecules such as alcohol, nicotine, certain drugs, and anesthetics cannot. Additionally, most antibiotics/medications, urea, and certain toxins are also unable to cross the BBB.

Cocaine blocks the reuptake of dopamine and norepinephrine in the brain. Dopamine is a neurotransmitter associated with pleasure and reward, while norepinephrine is involved in the body's "fight or flight" response. By blocking the reuptake of these hormones, cocaine increases their levels in the brain, leading to heightened feelings of euphoria and increased alertness.

Endorphins are a hormone that acts as a natural painkiller and is produced in response to high levels of stress. They are found in high levels in runners, which is why runners often experience a state of euphoria known as runner's high. Morphine, a powerful painkiller, binds to endorphins. Therefore, endorphins are the correct answer to the question.

The neurilemma is the outermost layer of the Schwann cell, which is a type of glial cell found in the peripheral nervous system. The function of the Schwann cell is to assist in the regeneration of injured axons. The neurilemma plays a crucial role in this process by providing a pathway for the regrowth of damaged axons. It forms a protective sheath around the axon and aids in the repair and regrowth of the nerve fiber. Therefore, the correct answer is neurilemma.