Nervous system - Biology

What is the function of the central nervous system?

• To regulate body temperature
• To control involuntary movements
• To process and respond to information from the body
• To transport blood
• To store nutrients

Answer explanation

The CNS processes all signals and coordinates responses.

Which part of the neuron transmits impulses away from the cell body?

• Axon
• Dendrite
• Synaptic cleft
• Nucleus
• Receptors

Answer explanation

The axon carries impulses away from the neuron’s cell body.

What are neurotransmitters?

• Electrical signals between neurons
• Chemical messengers that cross synapses
• Hormones released into the bloodstream
• DNA in the nucleus of a neuron
• Proteins that make up the cell membrane

Answer explanation

Neurotransmitters are chemicals released from neurons to communicate across synapses.

Which structure protects the brain and spinal cord?

• Myelin sheath
• Synaptic cleft
• Meninges
• Axon terminal
• Dendrites

Answer explanation

The meninges are protective coverings around the brain and spinal cord.

What is the role of sensory neurons?

• To send signals to muscles
• To connect the brain and spinal cord
• To carry impulses from sensory organs to the CNS
• To regulate hormone levels
• To process voluntary movements

Answer explanation

Sensory neurons carry signals from sensory organs (e.g., skin, eyes) to the CNS.

Which part of the brain controls vital functions like heart rate and breathing?

• Cerebrum
• Cerebellum
• Medulla oblongata
• Thalamus
• Pons

Answer explanation

The medulla oblongata controls vital functions like breathing and heart rate.

What is the main function of the cerebellum?

• Control breathing
• Maintain balance and coordinate voluntary movements
• Process visual information
• Regulate body temperature
• Produce hormones

Answer explanation

The cerebellum coordinates voluntary movements and helps maintain balance.

What happens when the action potential reaches the presynaptic neuron?

• Neurotransmitters are released into the synaptic cleft
• The neuron stops functioning
• The action potential fades away
• Potassium ions enter the neuron
• The neuron repairs itself

Answer explanation

When the action potential reaches the presynaptic neuron, neurotransmitters are released into the synaptic cleft.

What part of the neuron contains the nucleus?

• Dendrite
• Axon
• Synaptic terminal
• Cell body
• Receptors

Answer explanation

The cell body (soma) contains the nucleus and organelles.

What ion is responsible for initiating an action potential?

• Sodium ions
• Potassium ions
• Calcium ions
• Chloride ions
• Magnesium ions

Answer explanation

Sodium ions flow into the neuron to initiate an action potential.