physics chapter 3 section 1

Question 1

Question

Answer 1

Answer

Question 2

What is required for the nervous system to send signals throughout the body?

Answer 2

Electricity is required for the nervous system to send signals throughout the body and to the brain, making it possible for us to move, think, and feel.

Question 3

What are the main functions of electricity in the human body?

Answer 3

Electricity is needed for nerve impulse conduction, sensory information acquisition and processing, electrochemical activity, information transfer in the brain, and excitation conditions in the heart.

Question 4

Which elements in our bodies are electrically charged?

Answer 4

Sodium, potassium, calcium, and magnesium are elements in our bodies that have specific electrical charges.

Question 5

What are ions?

Answer 5

Ions are charged elements used by almost all of our cells to generate electricity.

Question 6

What is the role of the cell membrane in generating electrical currents?

Answer 6

The cell membrane acts as a barrier to molecules and allows the cell to generate electrical currents by controlling the flow of charged ions.

Question 7

How do cells achieve charge separation?

Answer 7

Cells achieve charge separation by allowing charged ions to flow in and out through the cell membrane. This creates an imbalance of positive and negative ions across the membrane, generating electrical currents.

Question 8

What are ion channels, and what do they do?

Answer 8

Ion channels are proteins that sit on the cell surface and create an opening for specific ions to pass through, controlling the flow of charged elements across the membrane.

Question 9

What happens when a cell is stimulated electrically?

Answer 9

When a cell is stimulated, it allows positive charges to enter through open ion channels, causing the inside of the cell to become more positively charged, triggering action potentials.

Question 10

What is an action potential?

Answer 10

An action potential is an electrical pulse generated by the flow of charges across the cell membrane, which is used by the body to initiate movements, thoughts, and behaviors.

Question 11

What is a neuron, and how does it transmit signals?

Answer 11

A neuron is an electrically excitable cell that processes and transmits information via electrical and chemical signaling, using structures like dendrites and an axon.

Question 12

What are dendrites, and what is their function?

Answer 12

Dendrites are thin structures that extend from the cell body, branching multiple times to form a dendritic tree, receiving signals from other neurons.

Question 13

What is an axon, and what does it do?

Answer 13

An axon is a special cellular extension that arises from the cell body and transmits electrical signals over long distances within the body.

Question 14

What influences the movement of ions across the neuron cell membrane?

Answer 14

Ions are influenced by membrane permeability, diffusion, and electric fields and potentials.

Question 15

What is the difference between diffusion of ions and diffusion of non-charged molecules?

Answer 15

Ions diffuse based on concentration and electric potential, while non-charged molecules diffuse only based on concentration gradients.

Question 16

What is membrane potential?

Answer 16

Membrane potential refers to the separation of opposite charges across the plasma membrane, with a slight excess of positive charges outside and negative charges inside the cell.

Question 17

How is membrane potential generated in biological organisms?

Answer 17

Membrane potential is generated by the unequal distribution of key ions (Na+ and K+) between the intracellular fluid (ICF) and extracellular fluid (ECF) and their selective movement through the plasma membrane.

Question 18

What separates the intracellular fluid (ICF) and extracellular fluid (ECF)?

Answer 18

The ICF and ECF are separated by a semi-permeable cell membrane that is permeable to water but not to most solutes, including electrolytes and proteins.

Question 19

What is diffusion, and what are its properties?

Answer 19

Diffusion is the spontaneous movement of particles from an area of high concentration to low concentration, requiring no energy and occurring via random kinetic movement.