MYP4-5 Exploring the Nervous System

What are the main components of the central nervous system?

• The liver and kidneys

• The heart and lungs

• The stomach and intestines

• The brain and spinal cord

How do neurons communicate with each other?

• Neurons communicate by direct contact without any chemical signals.

• Neurons use hormones to transmit signals between each other.

• Neurons communicate via synaptic transmission using neurotransmitters.

• Neurons communicate through electrical impulses only.

What is the role of synapses in neural communication?

• Synapses enable neural communication by transmitting signals between neurons through neurotransmitter release.

• Synapses act as barriers preventing signal transmission between neurons.

• Synapses store neurotransmitters for long-term memory retention.

• Synapses are responsible for generating electrical impulses in neurons.

Describe the pathway of a reflex arc.

• Sensory receptor, motor neuron, spinal cord or brain, effector

• Sensory receptor, sensory neuron, spinal cord (interneuron or relay neuron), motor neuron, and effector.

• Motor neuron, effector, sensory neuron, spinal cord, brain

• Sensory neuron, spinal cord, sensory receptor, effector, motor neuron

What is the function of sensory neurons in a reflex arc?

• To detect stimuli and transmit sensory information to the spinal cord.

• To enhance motor neuron activity during reflex actions.

• To process and store sensory information in the brain.

• To regulate the speed of reflex responses in the body.

How do motor neurons contribute to reflex actions?

• Motor neurons enable rapid muscle contractions in response to stimuli during reflex actions.

• Motor neurons inhibit muscle contractions during reflex actions.

• Motor neurons transmit sensory information to the brain.

• Motor neurons are responsible for processing visual stimuli.

What are neurotransmitters and why are they important?

• They are hormones that regulate the effectiveness of a stimulus.

• Neurotransmitters are only found in the brain and have no other functions.

• Neurotransmitters are chemical substances that transmit signals between neurons.

• Neurotransmitters are waste products of nerve cells that need to be eliminated.

Common neurotransmitters are...

• Norepinephrine and epinephrine

• Dopamine and serotonin

• Acetylcholine and adrenalin

• Glutamate and ethylene

What is an action potential and how does it occur?

• An action potential is a rapid change in membrane potential involving depolarization and repolarization phases.

• An action potential is a type of neurotransmitter released by neurons.

• An action potential is a slow change in membrane potential that only occurs in muscle cells.

• An action potential is a process that only involves the influx of potassium ions.

Explain the process of depolarization in an action potential.

• Depolarization occurs when sodium ions enter the neuron, making the inside more positive.

• Depolarization is the process of neurotransmitters binding to receptors on the neuron surface.

• Depolarization occurs when potassium ions leave the neuron, making the inside more negative.

• Depolarization happens when calcium ions are released from the neuron, causing a decrease in voltage.