Biomed II Part 2

Differentiate between the central and peripheral nervous systems.

The central nervous system (CNS) includes the brain and spinal cord; the peripheral nervous system (PNS) includes all nerves outside the CNS that connect it to the body.

What is the cerebrum?

The largest part of the brain, divided into four lobes (frontal, parietal, temporal, occipital) responsible for higher brain functions like thought, movement, and sensation.

What is the cerebellum?

A part of the brain located under the cerebrum that helps coordinate voluntary movement, balance, and posture.

What is the brainstem?

Made of the medulla oblongata, pons, and midbrain; controls vital functions like breathing, blood pressure, and sleep/wake cycles.

Which brain lobe controls reasoning, problem-solving, and voluntary movements?

The frontal lobe.

Which brain lobe processes sensory information such as touch, temperature, and pain?

The parietal lobe.

Which brain lobe processes sound and helps with understanding language?

The temporal lobe.

Which brain lobe is responsible for visual perception?

The occipital lobe.

Which part of the brain coordinates muscle control and balance?

The cerebellum.

Which part of the brain controls breathing and heart rate?

The medulla oblongata (part of the brainstem).

Which part of the brain connects the left and right hemispheres?

The corpus callosum.

Which part of the brain regulates temperature, hunger, thirst, and emotions?

The hypothalamus.

What are gyri and sulci?

Gyri are ridges on the brain’s surface; sulci are the grooves or valleys between them.

What are glial cells?

Cells that support, protect, and maintain homeostasis for neurons in the nervous system.

What are the main parts of a neuron?

Dendrites, cell body, axon, myelin sheath, nodes of Ranvier, and axon terminals.

What do sensory neurons do?

Carry information from sensory receptors to the brain and spinal cord.

What do interneurons do?

Connect neurons within the brain and spinal cord to process information.

What do motor neurons do?

Send signals from the brain or spinal cord to muscles to cause movement.

What does the sodium-potassium pump do?

Moves 3 sodium ions out of the neuron and 2 potassium ions in to maintain resting potential using ATP.

What is the resting membrane potential of a neuron?

About -70 mV.

During depolarization, which channels open?

Sodium channels open and sodium ions rush into the cell.

During repolarization, which channels open?

Potassium channels open and potassium ions leave the cell.

What happens at a synapse?

Neurotransmitters are released from the axon terminal, cross the synaptic cleft, and bind to receptors on the next neuron.

What is the role of acetylcholine?

A neurotransmitter that enables muscle contraction, learning, and memory.

What is the role of dopamine?

A neurotransmitter involved in pleasure, motivation, and movement.

What is the role of serotonin?

Regulates mood, sleep, and digestion.

What is the role of GABA?

The main inhibitory neurotransmitter that reduces neuron activity.

What is the role of glutamate?

The main excitatory neurotransmitter that stimulates neuron activity.

What is the role of epinephrine and norepinephrine?

Neurotransmitters involved in the body’s fight-or-flight response.

What is an agonist?

A substance that binds to a receptor and activates it to produce a response.

What is an antagonist?

A substance that binds to a receptor and blocks it from being activated.

What is an inverse agonist?

A substance that binds to a receptor and produces the opposite effect of an agonist.

What is a reuptake inhibitor?

A substance that prevents neurotransmitters from being reabsorbed, increasing their availability in the synapse.

What is the difference between a reflex and a reaction?

A reflex is an automatic, involuntary response; a reaction is voluntary and requires brain processing.