Neuroscience And Behavior/ Guided Lecture 1

Dendrites are the part of a neuron that receive information from other neurons. They are responsible for receiving signals and transmitting them to the cell body of the neuron. Dendrites have branches that grow in size when stimulated, allowing for increased connectivity and communication between neurons.

The myelin sheath is a protective covering around nerve fibers that helps to facilitate the transmission of electrical signals between neurons. If the myelin sheath disintegrates, it can disrupt the normal flow of these signals, leading to a decrease in neural speed. This can result in the development of multiple sclerosis, a neurological disorder characterized by impaired communication between the brain and the rest of the body.

A lack of acetylcholine, a neurotransmitter involved in memory and learning, has been linked to the development of Alzheimer's disease. Acetylcholine plays a crucial role in transmitting signals between nerve cells in the brain, and a deficiency of this neurotransmitter can impair cognitive function and contribute to the progression of Alzheimer's. Therefore, it is true that a lack of acetylcholine could lead to Alzheimer's disease.

The peripheral nervous system is responsible for connecting the body to the central nervous system. It consists of nerves that extend from the brain and spinal cord to various parts of the body. These nerves transmit signals between the central nervous system and the rest of the body, allowing for communication and coordination of bodily functions. The somatic, parasympathetic, and sympathetic nervous systems are all components of the peripheral nervous system, but the peripheral nervous system as a whole is the correct answer as it encompasses all of these systems.

During the refractory period or state of hyperpolarization, a neuron is not capable of firing an action potential. This is because the refractory period is a brief period of time after an action potential where the neuron is temporarily unable to generate another action potential. Hyperpolarization refers to a state where the neuron's membrane potential becomes more negative than its resting potential, making it even more difficult for an action potential to occur. Therefore, the statement that a neuron is capable of firing an action potential during the refractory period or state of hyperpolarization is false.

An action potential is a brief electrical signal that travels along a neuron. It occurs when the neuron's membrane potential reaches a certain threshold. The resting potential of a neuron refers to its charge when it is not actively sending a signal. A resting potential of -70 charge means that the inside of the neuron is more negatively charged compared to the outside. This negative charge difference is necessary for an action potential to occur. Therefore, the statement that an action potential requires a neuron to be at -70 charge, referred to as the resting potential, is true.

The somatic nervous system controls voluntary movements within the body. It is responsible for transmitting sensory information from the body to the central nervous system and for transmitting motor commands from the central nervous system to the muscles. This system allows us to consciously control our movements, such as walking, talking, and writing.

The correct answer is CNS, which stands for Central Nervous System. The central nervous system is made up of the brain and spinal cord. It is responsible for processing and coordinating information received from the sensory organs and sending out signals to the rest of the body. The brain controls functions such as thoughts, emotions, and voluntary movements, while the spinal cord acts as a pathway for transmitting signals between the brain and the body.

Sensory neurons transmit information from the environment through afferent nerves to the central nervous system. Once in the central nervous system, interneurons process and relay this information, allowing for communication between different parts of the central nervous system. This relayed information then activates motor neurons, which carry out actions through efferent nerves in the peripheral nervous system. Therefore, interneurons play a crucial role in connecting sensory input to motor output within the central nervous system.

Agonists are drugs that are designed to mimic a neurotransmitter. They bind to and activate the same receptors as the neurotransmitter, producing a similar effect. This can enhance or mimic the natural signaling of the neurotransmitter in the brain, leading to various physiological and behavioral effects. Agonists can be used therapeutically to replace or enhance the function of a neurotransmitter that may be deficient or dysfunctional in certain conditions. Overall, agonists play a crucial role in pharmacology by mimicking neurotransmitters and modulating their effects in the body.