Nervous System Overview

<p>Dendrites (C)</p> Signup and view all the answers

<p>Myelin (A)</p> Signup and view all the answers

<p>Afferent neuron (C)</p> Signup and view all the answers

<p>Nodes of Ranvier (A)</p> Signup and view all the answers

<p>Perineurium (C)</p> Signup and view all the answers

<p>Photoreceptors (A)</p> Signup and view all the answers

<p>Adaptation (A)</p> Signup and view all the answers

<p>Bell palsy (B)</p> Signup and view all the answers

<p>Afferent (A)</p> Signup and view all the answers

<p>Sciatica (D)</p> Signup and view all the answers

<p>Reflexive contraction (C)</p> Signup and view all the answers

<p>One muscle contracts while its antagonist relaxes (B)</p> Signup and view all the answers

<p>Dopamine (C)</p> Signup and view all the answers

<p>Multiple sclerosis (D)</p> Signup and view all the answers

<p>Autism (D)</p> Signup and view all the answers

<p>Balances sodium and potassium ions across the membrane (B)</p> Signup and view all the answers

<p>Refractory period (A)</p> Signup and view all the answers

<p>Synaptic transmission (A)</p> Signup and view all the answers

<p>Acetylcholine (C)</p> Signup and view all the answers

<p>Dura mater (D)</p> Signup and view all the answers

<p>Hypothalamus (A)</p> Signup and view all the answers

<p>Cerebellum (B)</p> Signup and view all the answers

<p>Pia mater (C)</p> Signup and view all the answers

<p>To protect brain tissue from toxins and pathogens (C)</p> Signup and view all the answers

<p>Vagus nerve (D)</p> Signup and view all the answers

<p>Reflex (C)</p> Signup and view all the answers

<p>Prepares the body for 'fight or flight' (D)</p> Signup and view all the answers

<p>Dermatome (D)</p> Signup and view all the answers

<p>Sulci (B)</p> Signup and view all the answers

The body system that works with the nervous system to maintain a stable internal environment. It releases hormones that regulate various processes, like growth, metabolism, and mood.

This system is responsible for receiving sensory information from the body and then sending commands to muscles and glands to produce responses.

This division of the nervous system contains the brain and spinal cord, which are responsible for processing and integrating information.

These cells support and protect neurons, the main cells of the nervous system. They provide nutrients and insulation to neurons.

A fatty covering that surrounds neurons, increasing the speed of signal transmission. It acts as an insulator for the nerve impulse.

The outermost layer of the myelin sheath, which is essential for nerve regeneration.

Small gaps between the myelin sheath along an axon, allowing for faster signal transmission.

The fundamental unit of the nervous system, responsible for transmitting electrical signals throughout the body.

Sympathetic stimulation increases the heart rate and strength of contraction.

The sense of smell is also known as olfaction.

Photoreceptors are specialized sensory cells located in the retina of the eye that are responsible for capturing light and converting it into signals that the brain can interpret.

Mechanoreceptors are sensory receptors that detect mechanical stimuli such as pressure, touch, and vibrations.

Adaptation is a decrease in sensitivity to a prolonged stimulus.

Proprioceptors are sensory receptors located in muscles, tendons, and joints that provide information about body position and movement.

The law of reciprocal innervation states that when a muscle contracts, its antagonist muscle is simultaneously inhibited.

When a muscle is passively stretched, muscle spindles are activated, triggering a reflexive contraction to prevent overstretching.

The Golgi tendon organ is a sensory receptor found in tendons that detects muscle tension and initiates the autogenic inhibition reflex to prevent over-contraction.

Alzheimer's disease is a neurodegenerative disease characterized by progressive decline in cognitive function, including memory, thinking, and language.

Sodium–potassium pump is a protein that actively pumps sodium ions out of the cell and potassium ions into the cell. This process helps maintain the resting membrane potential of a neuron, which is necessary for the transmission of nerve impulses.

Depolarization occurs when the membrane potential of a neuron becomes less negative. This happens when sodium ions rush into the cell, making the inside more positive. Depolarization is the first step in the generation of an action potential.

The refractory period is a brief period of time after an action potential during which a neuron is unable to generate another action potential. This ensures that impulses travel in one direction and prevents overstimulation.

The all-or-none principle states that a nerve impulse is either conducted at its full strength or not at all. There are no partial action potentials.

A synapse is a specialized junction where communication occurs between two neurons or between a neuron and a target cell, such as a muscle or gland.

Neurotransmitters are chemical messengers that transmit signals across the synaptic cleft. They are stored in synaptic vesicles and released when an action potential arrives at the presynaptic terminal.

The synaptic bulb is the swollen terminal of a presynaptic neuron that contains synaptic vesicles filled with neurotransmitters. These vesicles release neurotransmitters into the synaptic cleft.

Reuptake is the process by which released neurotransmitters are absorbed back into the presynaptic neuron. This helps regulate synaptic activity.

Acetylcholine is a neurotransmitter that plays a vital role in muscle contraction and other functions, such as memory and learning.

Neurotransmitters are chemical messengers that transmit signals across synapses. Some common examples include gamma-aminobutyric acid (GABA) and acetylcholine.

Meninges are protective membranes that surround the brain and spinal cord. They provide support and protection to these delicate structures.

Pia mater is the innermost layer of the meninges, directly adjacent to the brain and spinal cord. Arachnoid is the middle layer, resembling a spider web. Dura mater is the outermost layer, tough and fibrous.

Cerebrospinal fluid (CSF) is a clear fluid that surrounds the brain and spinal cord. It provides cushioning, removes waste, and supplies nutrients to the central nervous system.

The blood-brain barrier is a selective barrier that regulates the passage of substances from the bloodstream into the central nervous system. It protects the CNS from harmful substances.

The major regions of the brain are the cerebrum, diencephalon, cerebellum, and brainstem. Each region is responsible for specific functions, such as controlling movement, processing sensory information, and regulating vital functions.