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Flashcards in Introduction to the Nervous System Deck (55)
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1
Q

Learning Objectives

A

Review the function and general organization of the central and peripheral nervous systems
Summarize the differences between gray and white matter with regard to location, composition, and nomenclature.
Contrast the general features of the sympathetic and parasympathetic nervous systems.
Briefly describe the meningeal layers of the brain and spinal cord.
Identify the major areas of the ventricular system.
Identify the different lobes and divisions of the brain and their associated functions.
Describe the features of a transverse section of spinal cord.
Briefly describe the basic anatomy of a typical spinal nerve.

2
Q

What does the Central nervous system consist of?

A

Consists of the spinal cord, brain stem, cerebellum and cerebrum

3
Q

What does Peripheral nervous system consist of?

A

Cranial and spinal nerves consisting of ganglia

4
Q

What does the encephalon (brain) consist of?

A

Consists of brain stem, cerebellum and cerebrum

5
Q

What are three parts of the brain stem from superiorly to inferiorly?

A

Midbrain, medulla and pons

6
Q

Know where the CNS is and where the parts are anatomically

A

Use Flash cards to self test

7
Q

What is a neuron

A

An excitable nerve which transmits information as electric signals or action potentials

8
Q

What does a neuron consist of?

A

A neuron consists of a cell body (soma) and neurite. A neurite can either be an axon or dendrite

9
Q

What is an axon

A

An axon is a single long dendrite covered with myelin or Schwann sheath

10
Q

What is a dendrite?

A

They are short, multiple, thin neurites.

11
Q

What are glial cells?

A

Glial cells maintain homeostasis, form myelin, and provide support and protection for neurons in the central and peripheral nervous systems

12
Q

Name the glial cells in the PNS and their functions

A

Satellite cells: cells that cover the surface of nerve cell bodies in sensory, sympathetic and parasympathetic ganglia
Schwann cells: Myelin production

13
Q

Name the glial cells in the CNS and their functions

A

Oligodendrocytes: Myelin production
Astrocytes: Blood brain barrier
Microglia: Remove unwanted material
Ependymal cells: CSF production

14
Q

What does Myelin do?

A

Myelin makes electrical conduction faster and with less energy required

15
Q

What cell makes unmyelinated axons?

A

Oligodendrocytes

16
Q

Explain how neurons communicate

A

Neurons communicate through vesicles holding neurotransmitters in an axon going to the synapse and jumping across to the receptor of a dendrite

17
Q

What is a ganglion?

A

The ganglion is a group of nerve cell bodies where usually the synapse takes place

18
Q

What is gray matter?

A

Cell bodies of neurons and unmyelinated neurites

19
Q

What is white matter?

A

Usually myelinated axons

20
Q

Where do you find gray matter?

A

Grey matter is found on the surface of the brain and cerebellum and in the middle of the spinal cord

21
Q

Where do you find white matter?

A

On the brain it is deep from the grey matter and is found on the surface of the spinal cord

22
Q

What is afferent division?

A

Sensory neurons which conveys info from receptors in peripheral tissues and organs to the CNS

23
Q

What is efferent division?

A

Comprises motor neurons which transmits signals from CNS to the effector cells (skeletal and smooth muscles, organs and glands)

24
Q

Describe the basic task of the nervous system

A

A sensory input which is conveyed by afferent neurons goes to CNS. CNS decides to act on it by sending an impulse to the efferent neurons to the effector cells

25
Q

What is the somatic nervous system?

A

A type of efferent division. Innervation of skeletal muscles which are voluntary movement.

26
Q

What is the autonomic nervous system?

A

A type of efferent division. Innervation of smooth, cardiac muscles and glands which are involuntary movement

27
Q

What is the sympathetic system ?

A

A type of autonomic nervous system. Fight or flight

28
Q

What is the parasympathetic system?

A

A type of autonomic nervous system Rest and digest.

29
Q

Where can the sympathetic system be found?

A

Found at the lateral horn of T1-L2 spinal cord segments

30
Q

Where can the parasympathetic system be found?

A

Found at brain stem and S2-4 spinal cord segments

31
Q

What is the function of meninges?

A

Protect the CNS

32
Q

What are the layers of meninges from innermost to outermost?

A

Pia, arachnoid and dura

33
Q

Describe the Dura

A

The most superficial and toughest layer
Has 2 layers, inner meningeal and outer periosteal layer. In between is the dural septa which secures the brain to the skull, dampen movement of the brain in the cranial cavity and divide the cranial cavity into freely communicating compartments

34
Q

Describe the Arachnoid:

A

Web like structure near the dura

35
Q

Describe the pia

A

Deepest structure in contact with the CNS tissue and enters every sulci. Highly vascular

36
Q

Name the cerebral ventricles and locate them on flash cards

A

Lateral ventricle, 3rd and 4th centricle and central canal

37
Q

What is CSF and where does it get absorbed?

A

A clear, cell free fluid produced in the choroid plexus in the lateral and 3rd ventricles
It gets absorbed by arachnoid granulations into dural venous sinuses

38
Q

What does CSF do?

A

CSF acts as a cushion or buffer for the brain, providing basic mechanical and immunological protection to the brain inside the skull.

39
Q

What are Gyri and Sulci?

A

Gyri are outside grooves of the brain and the sulci are the deep foldings of the brain

40
Q

Describe the cerebrum in terms of layers.

A

Cerebral cortex, gray matter most superficial
Cerebral white matter
More gray matter most deep called nuclei

41
Q

Know the lobes of the brain and sulci and where they are using cue cards

A

Check cue cards

42
Q

What are the functions of the cerebrum?

A

Motor: Frontal lobe
Sensory:parietal lobe
Vision: occipital lobe
Auditory lobe: temporal lobe

43
Q

Difference between right and left hemisphere of brain

A

Left: Language and math skills
Right: visual spatial and creativity skills

44
Q

What does the diencephalon consist of?

A

Thalmus and Hypothalamus

45
Q

What does the thalmus do?

A

Major relay station for sense

46
Q

What does the hypothalamus do?

A

Autonomy control (para and symathetic), endocrine control, body temp, eating and sexual behavior

47
Q

Midbrain functions

A

Visual and auditory reflex sense, motor skills

48
Q

Pons functions

A

Conduction area between forebrain and cerebellum.

Respiration, hearing and balance

49
Q

Medulla functions

A

Crossing of of hemisphere axons

Vital centers regulating respiration, blood pressure, heart rate

Non vital centers regulating coughing, sneezing, swallowing and vomiting

50
Q

Explain the structure of the cerebellum

A

Convoluted with gray matter, white matter and nuclei.

Connect to the brain stem by superior, middle and inferior peducles

51
Q

Function of cerebellum

A

Coordinated of motor activity, and memory of motor activity. (riding a bike)

52
Q

Explain the structure of the spinal cord

A

A two way impulse conduction and reflex center which resides in the vetebral canal. Extends from the skull base but does not extend the length of the vertebral column

53
Q

Types of spinal segments

A
Cervical: 8
Thoracic: 12
Lumbar: 5
Sacral: 5
Coccygeal:1
54
Q

Types of spinal segments

A
Cervical: 8
Thoracic: 12
Lumbar: 5
Sacral: 5
Coccygeal: 1
55
Q

How does the spinal nerve work?

A

Answer in lecture slides