Biology Nervous System Quiz

The part of the nervous system responsible for controlling bodily functions that are not consciously controlled (e.g., heart rate, digestion, breathing). Examples include the sympathetic and parasympathetic nervous systems.

The division of the ANS that is responsible for "fight or flight" responses; involved in stress responses and preparing the body for physical activity.

The division of the ANS that is responsible for "rest and digest" functions; conserves energy, slows heart rate, and promotes digestion.

The part of the nervous system that controls voluntary movements. Examples include muscle movements like walking or writing.

The region of the nervous system that consists of the brain and spinal cord.

Neuronal tissues that extend out of the CNS and control various bodily functions.

The part of the PNS that carries signals from the CNS to muscles and glands.

The part of the PNS that carries signals from sensory organs to the CNS.

A type of glial cell that wraps around multiple neurons in the central nervous system (CNS), forming the myelin sheath that insulates axons and speeds up signal transmission.

A type of glial cell that provides a barrier between the blood and the brain, protecting the CNS from harmful substances and infections.

Small, phagocytic glial cells that act as the immune system of the brain, engulfing and digesting foreign particles and cellular debris.

A type of glial cell that lines the ventricles of the brain and acts as a barrier between the cerebrospinal fluid and the nervous tissue.

Specialized cells that transmit information throughout the nervous system using electrical and chemical signals.

The long, slender projection of a neuron that carries nerve impulses away from the cell body to other neurons, muscles, or glands.

Branch-like extensions of a neuron that receive signals from other neurons and transmit them to the cell body.

The junction between two neurons where a chemical signal is transmitted from one neuron to the next.

The efferent (motor) nervous system is responsible for carrying signals from the CNS to muscles and glands, enabling control over both voluntary (somatic) and involuntary (autonomic) functions.

Norepinephrine and acetylcholine are the primary neurotransmitters used by the efferent nervous system to communicate with muscles and glands.

All preganglionic neurons, which connect the CNS to ganglia, release acetylcholine, which binds to nicotinic receptors.

Postganglionic parasympathetic neurons release acetylcholine, which binds to muscarinic receptors, leading to 'rest and digest' effects.

Most postganglionic sympathetic neurons release norepinephrine, binding to α and β receptors, triggering 'fight or flight' responses.

The sympathetic and parasympathetic nervous systems differ in several ways, including the origin of their nerves, length of preganglionic fibers, location of ganglia, and length of postganglionic fibers.

The autonomic nervous system relies on a two-neuron pathway, starting with a preganglionic neuron in the CNS and ending with a postganglionic neuron in the effector organ.

These cells are the support system for neurons, ensuring their proper functioning and protection within the nervous system. They provide structure, insulation, and modulate neurotransmitter activity.

The sympathetic nervous system originates in the thoracic and lumbar regions of the spinal cord, while the parasympathetic system originates in the cranial and sacral regions.

A type of glial cell that produces the myelin sheath, a fatty covering that insulates axons, enabling faster and more efficient signal transmission in the nervous system.

Gaps between successive Schwann cells on an axon. These gaps facilitate rapid conduction of action potentials by allowing for saltatory conduction, where the electrical signal jumps from one node to the next.

This intricate covering around axons is made of lipoprotein material, called myelin, and is crucial for enhancing the speed and efficiency of nerve impulse transmissions.

This refers to the process of signal transmission across a synapse, where a neurotransmitter is released from a presynaptic neuron and binds to receptors on a postsynaptic neuron, triggering a response in the receiving cell.

A type of neurotransmission where electrical signals move directly from one neuron to another via gap junctions, found in some regions of the brain and other tissues.

This type of neurotransmission allows for more precise and nuanced responses, whereas electrical transmission operates on an all-or-nothing principle, sending a signal with fixed intensity.

The parasympathetic nervous system promotes bodily functions like digestion and energy conservation, often referred to as "rest and digest".

The sympathetic nervous system prepares the body for action, like a "fight or flight" response, by activating energy stores and enhancing alertness.

The adrenal cortex, a part of the adrenal gland, releases hormones like cortisol, aldosterone, and androgens, which contribute to stress response and energy regulation.

The adrenal medulla, another part of the adrenal gland, releases epinephrine and norepinephrine, which are neurotransmitters that intensify the "fight or flight" response.

Glycogenolysis, breakdown of glycogen for energy, is increased by the sympathetic nervous system, aiding in mobilizing energy during stressful situations.

The sympathetic nervous system activates glycogen phosphorylase, an enzyme that breaks down glycogen into glucose, providing energy during stress.

Glycogenesis, building up glycogen, is inhibited by the sympathetic nervous system, prioritizing energy utilization during stressful situations.

Glycolysis, breakdown of glucose for energy, is enhanced by the sympathetic nervous system, supplying energy for the body's immediate response.

Lipolysis, breakdown of fat for energy, is stimulated by the sympathetic nervous system, further contributing to energy mobilization during stress.

The sympathetic nervous system activates triglyceride lipase, an enzyme that breaks down stored fat (triglycerides) into fatty acids for energy production.

Most organs in the body are controlled by both the parasympathetic and sympathetic nervous systems. These systems often act in opposition, creating a balance.

The parasympathetic nervous system generally promotes rest and digestion, while the sympathetic nervous system prepares the body for action (fight or flight).

Dual innervation allows the body to respond quickly to changes in environment and maintain inner stability (homeostasis).

Dual innervation helps the body adapt quickly to various situations by allowing distinct responses under different conditions.

The sympathetic nervous system uses a chain of neurotransmitters, going from the neuron to the target organ, typically starting with acetylcholine and ending with norepinephrine.

Norepinephrine, a sympathetic neurotransmitter, inhibits the release of acetylcholine from parasympathetic neurons, leading to decreased gastrointestinal activity.

Various drugs can intervene with sympathetic neurotransmission by targeting different receptors or pathways.

Understanding the selectivity of drugs for different adrenergic receptors is key to achieving desired therapeutic effects and minimizing side effects.

The potency series for alpha adrenoreceptors ranks their affinity for epinephrine, norepinephrine, and isoproterenol.

Beta adrenoreceptors are categorized by their affinity for different agonists, with isoproterenol showing the highest affinity.

Dopamine receptors play a crucial role in regulating blood flow to vital organs, including the splanchnic, renal, and cerebral vasculature. However, few drugs specifically target dopamine receptor subtypes.

Drugs are classified as selective if they bind preferentially to one subgroup of receptors at low concentrations, minimizing interaction with other subtypes.

Epinephrine exhibits concentration-dependent selectivity, meaning its affinity for different receptor subtypes changes with its concentration.

Activation of alpha-1 receptors initiates a signaling cascade involving polyphosphoinositide hydrolysis, ultimately leading to the activation of protein kinase C.

Alpha-2 receptor activation inhibits adenylyl cyclase activity, leading to a decrease in cAMP levels. This action plays a role in regulating sympathetic tone and blood pressure.

Beta receptors, including beta-1, beta-2, and beta-3, activate adenylyl cyclase, increasing cAMP levels. This mechanism triggers diverse effects in different tissues, such as liver, heart, and smooth muscle.

Dopamine receptors, D1 and D2, activate different G-protein signaling pathways resulting in diverse effects on blood vessels and neurotransmitter release.

The nervous system is divided into the autonomic nervous system and the somatic nervous system, further subdivided into sympathetic and parasympathetic branches.

Glial cells support neurons, while neurons are the primary messengers that carry and transmit information throughout the system.

The synthesis of catecholamines is regulated by the enzyme tyrosine hydroxylase, while enzymes like monoamine oxidase and catechol-O-methyl transferase are involved in their breakdown.