Neurons, Synapses, and Signaling

Question 1

Neurons of vertebrates and most invertebrates require supporting cells called

Answer 1

glial cells (glia)

Question 2

What do glia cells do?

Answer 2

Nourish neurons, insulate the axons of neurons, and regulate the fluid of surrounding neurons

Question 3

Nervous systems process information in 3 stages

Answer 3

• Sensory input
  -Integration
  -Motor output

Question 4

Sensory neurons

Answer 4

transmit information about extenal stimuli or internal conditions

Question 5

Interneurons

Answer 5

integrate (analyze and interpret) the sensory input.
- They form local circuits connecting neurons in the brain or ganglia

Question 6

Motor neurons

Answer 6

transmit signals to muscle cells causing them to contract
- extend out of the processing centers trigger gland activity.

Question 7

Central Nervous System (Brain and spinal cord)

Answer 7

Neurons that carry out integration

Question 8

Peripheral nervous system (PNS)

Answer 8

Neurons that carry information into and out the central nervous system

Question 9

PNS neurons , bundled together form

Answer 9

nerves

Question 10

Depending on its role, the shape of a neuron

Answer 10

can vary considerably

Question 11

The relative inside of a cell

Answer 11

is negatively charged relative to the outside

Question 12

Membrane potential

Answer 12

when the potential energy is negative inside and positive outside

Question 13

The resting potential

Answer 13

the membrane potential of a neuron not sending signals.
- Changes in membrane potential, action potentials, act as signals, transmitting and processing information

Question 14

Potassium ions (K+) and sodium ions (Na+) play an essential role in forming the

Answer 14

resting potential

Question 15

In most neurons, the concentration of K+ is higher ___ the cell, while the concentration of Na+ is higher ____the cell

Answer 15

inside
outside

Question 16

Sodium-potassium pumps use the energy of ___ to maintain these K+ and Na+ gradients across the plasma

Answer 16

ATP

Question 17

Ion channels

Answer 17

pores formed by clusters of proteins that span the membrane

Question 18

Ion channels are selectively permeable, allowing

Answer 18

only certain ions to pass through

Question 19

Leak channels

Answer 19

A resting neuron has many that has many open potassium channels allowing K+ to flow out

Question 20

What is the major source of membrane potential?

Answer 20

The resulting buildup of negative charge inside the neuron