Neuron BIOLOGY

Question 1

What are the 3 types of sensory Receptors

Answer 1

Interceptors
Monitor internal systems such as digestive,Respiratory,reproductive
And internal senses taste,pain

Exterioceptors
External sense such as touch,temperature and sight and smell

Proprioceptors
Monitor position and movement

Question 2

What are the two major efferent systems?

Answer 2

Somatic nervous system
Autonomic nervous system

Question 3

Where do signals from CNS motor neurons to visceral effectors pass synapses at autonomic ganglia?

Answer 3

Preganglionic and Postganglioc fibers

Question 4

What is the function of interneurons?

Answer 4

Distribution of sensory information and coordination of motor activity
Also involved in memory,planning and learning

Question 5

What is the reflex arc?

Answer 5

It us a signal conduction from the cns and involves interneurons,afferent and efferent neurons
Affarent neurons conduct impulses to the Cns
Interneurons carry information and process it
The efferent will conduct impulses from the cns to the effectors(muscles)

Question 6

What are the five main membrane processes in neural activities?

Answer 6

Resting Potential
Graded Potential
Action Potential
Synaptic activity
Information Processing

Question 7

What us the the Resting Potential?

Answer 7

It is the transmembrane potential of a resting cell

Question 8

What is a graded Potential?

Answer 8

Temporary change in a resting potential

Question 9

What is an action Potential?

Answer 9

It is an electrical impulse
And is produced by a graded potential and moves along the axon to the synapse

Question 10

What is synaptic activity?

Answer 10

Releases NTS in the presynaptic membrane and produces graded potentials in the postsynaptic membrane

Question 11

What is information processing?

Answer 11

Response of postsynaptic cell

Question 12

What is the diffrence in electric charge?

Answer 12

Potential

Question 13

What is a membrane potential?

Answer 13

It is a diffrence in concentration of ions (outside there’s an excess of positive ions and inside there’s a slight deficit in positively charged ions

Question 14

What is the magnitude of potential difference between 3 sides of polarized membrane?

Answer 14

Volts or Milivolts

Question 15

What are the 3 important concepts of a transmembrane potential?

Answer 15

Extracellular fluid and intracellular fluid differ greatly in ionic composition
And cells have a selectively permeable membrane
And membrane permeability varies by ion

Question 16

What are the passive forces acting across a plasma membrane?

Answer 16

Chemical gradients -
Electrical gradient
Equilibrium potential-the transmembrane potential at which there’s no net movement of a particular ion across a cell membrane

Question 17

What is the sodium potassium pump?

Answer 17

An active transport mechanism which involves Na and K ions moving in opposite directions
It maintains an imbalance of distribution of positive ions
And the inside becomes slightly more negative than the outside
The pump ejects 3 Na and brings in 2 K into the cell
It serves to stabilize the resting potential

Question 18

What are local potentials ?

Answer 18

Excitation
When a stimulus triggers the opening of additional Na channels and membrane potential moves towards 0(Depolarization)

Inhibitation
Stimulus triggers opening of K channels increasing membrane potential(hyperpolarisation)

Question 19

What is the mechanism that produces an action potential?

Answer 19

Stimulus gated Na channels open
Na diffuses into the cell this is called local deploarization.
Threshold potential Then the Na channels open further causing more Na to enter cell
Action potential peaks and then moves back to resting potential and K gates open causing K to move out of cell this is called repolarization
A brief moment if hyperpolarisation occurs
Then causing resting potential to restore

Question 20

What is the refractory period?

Answer 20

Neuron is incapable of producing another action potential

Question 21

What is the absolute refractory period?

Answer 21

It is a brief period during which a local area of neurons membrane resists restimulation no matter how strong

Question 22

What is relative refractory period?

Answer 22

When the membrane is repolarized and restoring resting membrane potential it will respond to only strong stimulus

Question 23

What are the types of synapses?

Answer 23

Neuromuscular
Neuron and muscle
Neuroglandular
Neuron and gland

Question 24

What are neuronal pools?

Answer 24

Finctional groups of interconnected neurons with limited input sources and output destinations
May stimulate or depress a part of the brain

Question 25

What are the 5 patterns of neuronal circuits in neuronal pools?

Answer 25

Divergence-spreads stimulation to many neurons
Convergence -brings input from many sources to single neuron
Serial processing -moves info in a single line
Paraell processing -moves same info along several paths at the same time
Reverberation -positive feedback mechanism

Question 26

What is Receptor potential?

Answer 26

It is a potential that develops when there is enough stimulus that acts on a receptor
When threshold is reached an AP in sensory neuron axon is triggered

Question 27

What is adaptation?

Answer 27

A functional characteristic of receptors
Receptor potential Decreases overtime in response to continuous stimulus
Leading to a decreased rate of impulse conduction and Decreases sensation

Question 28

What is a primary response of sensory receptors?

Answer 28

Have axons that can conduct an AP in response to receptor potential

Question 29

What is a secondary response of sensory receptors ?

Answer 29

Have no axons and receptor potential produced and no AP but release NTs