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Flashcards in Nervous System Deck (54)
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1

What are the two sections that the nervous system is divided into?

CNS
PNS

2

What does CNS stand for?

Central nervous system

3

What is the central nervous system comprised of?

Brain and Spinal cord

4

What's does PNS stand for

Peripheral Nervous System

5

What is the PNS made up of?

All the other neurons outside the CNS

6

What does the nervous system allow the body to do?

Allows the organism to react to the stimulus very quickly.

7

What are the responses like of nervous system?

Rapid and short

8

What are the two parts of the PNS?

-Sensory division
-Motor Division

9

Outline the role of the sensory division

Transmits information to the CNS

10

Outline the role of the motor division.

Transmits information away from the CNS

11

What are the roles of the somatic sensory neurons?

Transmits information to the CNS from the external environment via senses

12

What is the role of visceral sensory neurons?

Transmits information to the CNS from the internal environment e.g organ

13

What are the two systems of motor division?

Somatic Nervous System
Autonomic Nervous a System

14

What is the role of the somatic nervous system?

Transmits messages to skeletal muscles. This is a VOLUNTARY system

15

What is the role of the autonomic nervous system

It is an involuntary system
It sends messages to smooth muscles, heart muscle and glands as humans cannot control these things

16

What are the two sections of the autonomic nervous system

-Sympathetic
-Parasympathetic

17

Explain synaptic signalling

Nerve cells releases neurotransmitter molecules into synaptic celft, stimulating target cell

18

What are responses to the changed dectected by the nervous system like?

Rapid and short

19

What is a nerve cell called

A neuron

20

What sort of impulses do neurons transmit?

Electrical

21

Function:Cell body in neuron

Mass of cytoplasm with contains a nucleus, from which branches of neurons arise

22

Function: Axon

Carry information away from the cell body to another neuron or tissue

23

Function Dendrites

Recieve stimuli from other cells

24

Function Synaptic terminals

Communicate with other cells
located on the dendrites

25

Function myelin sheath

increases speed of electrical impulses and insulates against loss of impulses for the neuron

26

Function Nodes of Ranvier

Impulses jump from one to the next hence creating a more rapid impulse


(spaces in between the myelin sheath)

27

Function Axon Terminal

Release neurotransmitter to next cell

28

Three types of neurons

-Sensory
-Interneurons
-Motor Neurons

29

Function- Sensory neurons

Carry sensory information from the receptors to the CNS

30

Function- Interneurons

Form connections or links between other nuerons in the CNS

31

Function- Motor Neurons

Carry information from the CNS to the effectors to generate a response

32

Definition of a nerve

A bundle of motor neurons and or sensory neurons with tissue and bloo vesscles.

33

What initially begins action potential?

When a signal binds to a receptor on a dendrite it creates an electrical impulse which travels along the axon to the axon terminal

34

What happens when the electrical impulses reaches the axon terminal?

Releases a neurotransmitter which will either move to the enxt neuron or effector via brownian motion

35

Explain the resting state of a neuron

Potassium inside
Sodium Outside
Hence a resting state of an overall negative charge inside the neurone.

36

What happens to the membrane when the signal binds to the dendrite?

It becomes more permeable to sodium ions and they rush into the cell

37

What is known as action potential

The temporary charge outside the neuron when sodium ions rush into the neuron via the protein channels

38

Does action potential move in sections?

Yes

39

What happens after the impulse has moved along the neuron

It will return back to its resting state, and will repolarise

40

Define neurohormones

Hormones released into the bloodstream and are produced by neurosecretory cells

41

What is the synapses?

The region at the end of an axon

42

What are neurotransmitters?

Proteins in which are chemical messengers and exit the neurone via secretory vesicles. They will then diffuse across the synapse and join to protein receptors on the membrane of a dendrite, muscle or gland.

43

What are the two types of neurotransmitters?

Excitatory
Inhibitory

44

What is the neuromuscular junction

Synpase (gap) between a neuron and a muscle

45

Explain the ecitatoory synapse

-net low of positive charges into the cell, leaving the cell depolarised
-leading to becoming closer to threshold

46

Explain the inhibitory synapse

-Membrane pushes even more negative than the resting state
-Cell then becomes hyperolarised
-Reduced chance of action potential

47

Role of meninges in brain

Membranes which enclose the brain

48

Cerebrospinal fluid

Fluid between membrane acts as cushioning to the CNS when it recieves a knock

49

Cerebrum

Controls all concsious actions

50

Cerebellum

Coordination of complex muscle movement

51

Thalumus

Recieves impluses from the sensory neurons and directs the message to a part of the brain

52

Hypothalamus

Regulates the release of hormones and controls other aspects of homeostasis.

53

What is a reflex arc?

A pathway from a receptor to effector that does not involve the brain

54

How do reflex arc work?

involuntary movement directly controlled by the spinal cord