The NERVOUS SYSTEM Flashcards

master all mntanami

You may prefer our related Brainscape-certified flashcards:
1
Q

what makes up the CNS

A

The spinal cord and the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what makes up the peripheral nervous system

A

nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are neurons and how do they function

A

cells responsible for nervous system signaling

they are specialized for communication.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are dendrites

be able to identify these Mnumzana

A

cytoplasmic extensions of the body

they receive information from other neurons and receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define an axon and its function

A

tube of the cell membrane
enclosed with the myelin sheath
it transmits Action Potential away from the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the function of Schwann cells

A

to create fatty myelin sheath in PNS

produce myelin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are oligodendrocytes

A

myelinating cells in the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

demyelination definition

A

loss of myelin sheath in the axons

caused by neurodegenerative autoimmune diseases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

diseases caused by demyelination of the axons

A

multiple sclerosis
Guillain Barre Syndrome
Acute encephalomyelitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is multiple sclerosis

A

an autoimmune disease that involves the loss of oligodendrocytes
the immune system attacks the nervous system leading to demyelination

disrupts the CNS from communicating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

how is Ms diagnosed?

A

based on signs and symptoms
supporting imaging and laboratory testing
(neuroimaging is used– which is the analysis of the cerebrospinal fluid and action potentials)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

during MS diagnosis using neuroimaging, what is the cerebrospinal fluid tested for

A

the cerebrospinal fluid is tested for Oligoclonal bands of IgG on electrophoresis( which are inflammation markers found in 75% to 85% of people with MS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the 3 stages of information processing?

A
  1. Input( sensory input) gathering of information
  2. Integration- processing of information
  3. Motor output- response to the information transmitted
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the 2 cells that make up the nervous system

A

neurons(20% of the nervous system)
A-N-D
glia cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the 3 types of neurons

A
  1. sensory( afferent) neurons
  2. Interneurons- connect neurons to specific regions of the CNS
  3. motor ( efferent) neurons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 types of Glia cells

A
  1. Microglia
  2. Astrocytes
  3. Oligodendrocytes and Schwann cells
  4. Ependymal cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Who is ONE person on Earth that you believe in the Most?

A

NKANYISO NELSON ZULU
THE GUY IS AMAZING AND CAPABLE OF ACHIEVING ANYTHING
HE MUST REMEMBER TO REMAIN DISCIPLINED AND BE CONSI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

BE ABLE TO IDENTIFY ALL GLIA CELLS IN A DIAGRAM

LET’S SEE DR. ZULU

A

YOU CAN DO IT. NEVER DOUBT YOURSELF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are glia cells?

A

glia means glue, and hence these cells can be understood to support the structure of the nervous system

maintain homeostasis
do not generate impulses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

neurons initiate action potentials

what is ACTION POTENTIAL?

A

transient (only lasting for a short time) alteration of the transmembrane voltage across an excitable membrane in an excitable cell
Generated by the activity of voltage-gated ion channels embedded in the membrane.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

definition of the resting/membrane potential

A

the difference in charge between the cell’s membrane and extracellular fluid when the cell is not electrically charged.

it results from ionic gradients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the function of the sodium/potassium pump

A

prevents leaking of ions and also prevents the cell gradients from running down.

the resting potential of neurons is -70mV. the pump maintains this PUMP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what happens if the resting potential of -70mV changes?

A

a neuron is triggered to fire and send electrical impulses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

there are two types of ion channels. What are these?

A

active channels

passive channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are graded potentials?

A

short-lived depolarizations or hyperpolarizations of the membrane

can only act as signals over short distances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is the difference between action potentials and graded potentials?

A

basically,
the sum of graded potentials that are enough to reach the triggering threshold is called ACTION POTENTIALS

it is only an action potential if it is greater than the threshold potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

explain what happens during hyperpolarization

A

membrane potential becomes negative(the cytoplasm/ inside of the membrane) becomes negative

K+ open and increase permeability to K+

hyperpolarization occurs after depolarization. as K+ ions exit, the inside of the cell because less and less positive…the graph goes down.

potential approaches -92mV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

explain what happens during depolarization

A

membrane potential becomes more positive as the opening of Na+ channels increases the permeability of Na+

potential approaches E(Na)= +62mV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

the change in the postsynaptic potential can be inhibitory or excitatory

A

I LOVE YOU BRO

YOU ARE CAPABLE. BELIEVE IN YOURSELF ALL THE TIME.

AND THE LORD SAID, “IT IS DONE”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

WHAT ARE THE METHODS BY WHICH IONS ENTER AND EXIT CELLS»>?

A
  1. Diffusion
  2. Ion channels
    ` passive
    ` voltage gated-> open in response to voltage
    Ligand-gated--> open in response to chemicals Stretch-gated—> mechanically transformed
  3. Ion pumps–which expand energy. eg. the sodium/ potassium pump.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is the role of voltage-gated ion channels in the Action Potential?

A

regulate the action potential by controlling what exits and enters the cell (Na+ or K+)
Allow Na+ to enter the cell during depolarization
Allow K+ to exit the cell during repolarization and hyperpolarization.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

how does the depolarization ( action potential) spread/ travel down the axons?

A

the influx of positive charges attracts negative charges inside the CELL, and repulses POSITIVE charges.

Because the Na+ channels have closed and the K+ continues to exit the cell, the membrane cannot depolarize again.

The action potential continues to travel down the AXON.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what is saltatory conduction?

A

The action potential travels down the axon by jumping from Node to Node.

saltatory conduction increases the speed of nerve impulse transmission

unmyelinated= 2,3 m/s
Myelinated= 110m/s
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what advantage does saltatory conduction prove in nerve impulse transmission?

A

saves neuron energy, as it Prevents slow inward leak of Na+ and outward leak of K+ because maintaining membrane potential requires ENERGY>

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

briefly explain how neurotransmitters are released?

A

Neurotransmitters are stored in synaptic vesicles at the ends of axons

AP reaches synaptic terminal it depolarises the terminal pre-synaptic membrane opening voltage-gated Ca2+ channels. Ca2+ then enters.

Calcium triggers exocytosis of neurotransmitters (held in membrane bound vesicles) into the synapse

Neurotransmitter diffuses across synaptic cleft – effect either direct or indirect

Many receptors for neurotransmitters are ligand-gated channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what happens to neurotransmitters after they are released from the presynaptic neuron.

A
  1. taken back presynaptic neurons and be repackaged into membrane-bound vesicles
  2. Destroyed by enzymes in the cleft
  3. diffuse away from the synaptic cleft and into circulation where they are later destroyed.
  4. Glia cells take up neurotransmitters and use them as a source of energy.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what does the response of postsynaptic cell to neurotransmitter depend on?

A
  1. Type of neurotransmitter
  2. The concentration of the neurotransmitter
  3. Types of receptors and chemically sensitive ion channels in the postsynaptic membrane.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

there are 8 examples that you need to know

what is adrenaline responsible for

A

flight or fight response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what is noradrenaline(norepinephrine) responsible for?

A

concentration transmitter
has excitatory or inhibitory effects in CNS and autonomic division of PNS

IN sympathetic nervous system, it increases heart rate, metabolizes fat, and increases muscle readiness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is dopamine

A

Pleasure neurotransmitter
feeling of pleasure

affects mood, sleep, appetite, and sexuality

can be both inhibitory or excitatory
found inside the brain, plays a role in motor control, motivation, arousal, reinforcement and reward

motivation, reward and addiction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Serotonin?

A

Mood neurotransmitter–
major targets for antidepressant drugs( many are Selective Serotonin Reuptake Inhibitor(SSRIs) increase concentration of serotonin in the synaptic cleft.
eg. Prozac (fluoxetine), Zoloft, Fontex- Enhance effect of serotonin by inhibiting its uptake after release.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what is GABA

A

calming neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Acetylcholine?

A

Learning neurotransmitter

most common- muscle simulation, memory and learning
excitatory or inhibitory in CNS depending on the type of receptor.

shortage of ACh leads to alzheimer’s disease, mental imparement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Glutamate?

A

Memory neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Endorphins?

A

Euphoria(a feeling or state of intense excitement and happiness) neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

what is Botulinum toxin or Botox?

A

Neuroprotein produced by the bacterium Clostridium botulinum

prevents the vesicle where ACh is stored from binding to the membrane where the neurotransmitter can be released

prevents muscle contraction for 3-4 months.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What are biogenic amines?

A

derived from amino acids

1.catecholamines- produced by amino acid- tyrosine
they include Epinephrine (adrenaline) , norepinephrine and dopamine.
2. Indolamines- derived from amino acid tryptophan
include serotonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what is Attention Deficit Hyperactivity Disorder

A

………..

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

DOPAMINE DISORDERS

A
  1. Parkison’s disease
  2. Schizophrenia
  3. Amphetamines and cocaine
  4. LSD and Mescaline ( psychoactive drugs)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what is Parkinson’s disease????????

A

Associated with reduced levels of dopamine neurons in the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

what is Schizophrenia?

A

Associated with abnormal levels of dopamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What effect do amphetamines and cocaine have on dopamine levels??

A

Increase dopamine levels, and hence excessive stimulation of the postsynaptic neurons.

53
Q

What are the effects of LSD and Mescaline?

A

Produce hallucinatory effects by binding to brain receptors for serotonin and dopamine.

54
Q

What is the Vertebrate CNS derived from?

A

Dorsal embryonic nerve cord

55
Q

What is the brain 🧠 made of?

Include the %

A

Water 💦 (78%)
Fat.(10%)
Protein(8%)

56
Q

The front section of the brain shows Gray and White matter

Define these 2 terms.

A

Gray matter– Neuron cell bodies

White matter– Bundled Axons

In the spinal cord, the white matter in on the outside, which shows its role in linking CNS to PNS.

In the brain, white matter plays a role in signalling between neurons for learning, emotions, senses etc.

57
Q

The brain 🧠 has 3 layers of protection

What are these layers?

A
  1. Bone-Skull
  2. 3 LAYERS OF CONNECTIVE TISSUE(Meninges)
  3. Cerebrospinal Fluid(CSF)–Liquor cerebrospinalis.
58
Q

What are the 3 layers of connective tissue(meninges) that protect the brain (among other 2 brain protections)???

A

Dura Mata (Outer)

Arachnoid (Middle)

Pia mater (Inner)

59
Q

Where is the cerebrospinal fluid(CFS) located?

A

It is located between Arachnoid and Pia mater.

60
Q

How does the Cerebrospinal fluid protein the brain?

A
It has Cushioning effect(physical barrier)
Chemical barrier (isolates from infection)
61
Q

What are the 3 major anatomical and function divisions of the brain?

A
  1. FOREBRAIN
  2. MIDBRAIN
  3. HINDBRAIN
62
Q

What is the Forebrain responsible for?

A

Determine complex behaviour and conscious thought.

Receives and integrates sensory input from External environment

63
Q

What is the function of the Midbrain?

A

Relays visual and auditory inputs

Monitors the unconscious movement of the muscles

64
Q

What is the Function of the HINDBRAIN?

A

Responsible for basic, automatic and vital tasks

Connected to the spinal cord

65
Q

The Forebrain has 4 functional lobes

Name these functional lobes and state their functions

A
  1. Frontal lobe
    Initial yes motor activity
    Responsible for speech and conscious thought.
  2. Parietal lobe
    Receives and interprets sensory information (from skin)
  3. Occipital lobe
    Processes visual information
  4. Temporal lobe
    Interprets auditory information.
    Comprehends spoken and written language.
    Perceptual judgement.
66
Q

What is the left hemisphere of the brain 🧠🧠🧠 responsible for (IN GENERAL)?,

A

Languages, mathematics, logical operations, sequences of information.

67
Q

Right hemisphere of the brain 🧠🧠🧠

A

Pattern and face recognition, spatial relations, non-verbal thinking, emotional processes.

68
Q

What is the function of the PNS?

A

Transmits information to and from the CNS

Regulated vertebrates movement and internal environment

Sensory neurons– from stimulus to the CNS receptors of the stimuli

Motor neurons–from CNS to the Muscles and Glands (CALLED EFFECTORS)

69
Q

There are 2 types of efferent neurons

Name these

A

1.Autonomic nervous system
Sympathetic division
Parasympathetic division
Enteric division

2.Motor system

70
Q

Functional components of the somatic or Motor divisions.

Describe the functions of the somatic/motor division and autonomic division.

A

Somatic/Motor—-√• Carries signals to and from skeletal muscles, mainly in response to external stimuli

Autonomic•√•√ Regulates internal environment by controlling smooth and cardiac muscle, and organs of digestive, cardiovascular, excretory and endocrine systems.

71
Q

$tate the Functions of the motor or somatic division of the PNS.

A

Conscious and involuntary control

Skeletal muscle actually controlled by reflexes mediated by Spinal cord and/or brainstem

72
Q

What are the 4 special senses?

A

Taste
Smell
Hearing
Sight

73
Q

Sensory receptors may be grouped to form sensory organs

What are sensory receptors?

A

Specialised cells or neuron ending that converts stimuli into electrical signals

The AP stimulates by light striking eye is the same as AP triggered by air vibrating in the ear.

74
Q

What is sensation?

A

Activation potentials that reach the brain 🧠🧠🧠 via sensory neurones, aware of stimulus.

75
Q

What is perception?

A

This is where the brain 🧠🧠🧠 interprets, giving understanding of what the sensation means.

76
Q

There are 6 types of sensations

Name these.

A
Visual(eyes)
Auditory(ears)
Olfactory (smell)
Gustatory(👅 tongue)
Somatosensory --cutaneous(skin) and proprioception (vestibular and kinesthetic)
Osmoreception(thirst)
77
Q

What are the functions of sensory receptors?

A
  1. Sensory transduction– change stimulus into electrical energy, change in membrane potential is known as Receptor potential, graded potentials.
  2. Amplification– enhancement of signal
  3. Transmission–Synapses
  4. Integration—Processing begins as soon as information is received,
78
Q

What are the 2 types of sensory receptors?

A
  1. Somatic sensations

2. Special senses

79
Q

What are somatic sensations ?

A

Originate from more than one location in body (temp, touch, vibration, pressure, pain, awareness of body movements)

80
Q

What are special senses?

A

Receptors that are restricted in particular areas in the body (taste, smell, hearing balance, Vision)
Highly specialised information about the external world.

81
Q

What are mechanoreceptors?

A

Receptors that sense physical deformation–pressure, touch, stretch, motion, sound

82
Q

There are 4 types of mechanoreceptors

Name these and their functions..

A
  1. Tactile receptors
  2. Proprioceptors
  3. Statocysts(in vertebrates)
  4. Hair cells
83
Q

What are tactile receptors?

A

°•located in the skin.

°•may simply be nerve endings or may form specialised receptors.

84
Q

Name the types of tactile receptors

Be able to identify these in a diagram

A

Meissner corpuscle

Merkel discs

Un-encapusulated dendritic endings

Pacinian corpuscle

Ruffino corpuscle

85
Q

What are proprioceptors (function) and where are they located?

A

Provide the information needed to distinguish different types of movement, by transducing changes in muscle shape and length

Located in muscles tendons and joints

Allow animal to perceive positions of body parts and overall position of the body.

They have little sensory adaptation–continuosly supply information.

86
Q

There are three main types of proprioceptors

Name them.

A
  1. Muscle spindles
  2. Golgi tendon organs
  3. Joint receptors.
87
Q

muscle spindles

Function

Location

A

Detect muscle movement
Located parallel to muscle fibres

Respond to stretch (tap patellar tendon)

88
Q

GOLGI TENDON ORGANS

function

Location

A

Monitor skeletal muscle tension

Stretch when muscle contracts

Located in dendrites around collagen in muscle-tendon junction..

89
Q

Joint receptors function

A

Monitors pressure, tension. And movement in JOINTS.

90
Q

What are statocysts (in invertebrates)band their function

A

Respond to gravity–ALLOW INVERTEBRATES TO MAINTAIN ORIENTATION WITH RESPECT TO GRAVITY.

91
Q

What are Hair cells and what are their function?s

A

These are sensory receptors responsible for functions of AUDITORY AND VESTIBULAR APPARATUS.

92
Q

What are chemoreceptors?

What are they responsible for?

A

These are sensory receptors that TRANSDUCE CHEMICAL COMPOUNDS INTO NEURAL IMPULSES.

Responsible for:::
Gustation( taste–chemicals dissolved in water) - occurs in Tatar buds

Olfaction–(smell–gaseous chemicals in air)–Occur in olfactory epithelium.

93
Q

Function of elctromagnetic receptors?

A

Transduce various forms of electromagnetic energy e.g. Light, Electricity and magnetism.

Well developed in fish and sharks and some mammals.

94
Q

What are thermoreceptors?

A

Detect temperature 🌡️🌡️🌡️ in internal and external environments.
Humans: located in skin and anterior hypothalamus

IR receptors in many 🐍 snakes.

95
Q

What do snakes use to detect prey?

A

Use infrared radiation

96
Q

Capsaicin is an active ingredient in spicy food. What receptor does it bind to?

A

Binds to a special class of Vanilloid receptor inside our mouth called VR1 receptors.

After capsaicin binds to these receptors, the sensory neuron is depolarized, and it sends along a signal indicating the presence of spicy stimuli.

97
Q

What are pain receptors (Nociceptors)

A

These are un-encapusulated endings near skin surface

Respond to excessive pressure, heat, light or chemicals. Density highest in Skin.

98
Q

There’s Fast and slow pain that can be detected by Nociceptors

Differentiate between these 2

A

Fast pain(sharp or acute pain)—Physical pressure, heat, near surface of body, strong withdrawal response.

Slow pain–Muscles or internal organs, chemically sensitive pain receptors, chemicals from damaged tissue(Histamine)

99
Q

I know all this can get Overwhelming

You will ask yourself if this is the correct way of studying

No matter what

There’s a person who’ll figure it out

Who’s that person?

A

NKANYISO NELSON ZULU

ME MYSELF AND I

100
Q

What are chemoreceptors responsible for in the Special senses?

A
  1. Taste

2. Smell

101
Q

Let’s dig a little bit deeper. Acquiring knowledge may be painful, but acquired knowledge is Golden, and Feels Good.

Anyway

What is taste
What makes up taste buds
Mammalian tongue

A

Chemical signal converted to action potential

The tongue is rough-Papillae, taste buds at surface of folds

There are 10 000 taste buds-mostly on 👅 tongue

Taste buds=25 taste cells and 25 supporting cells.

Taste hairs at tips||~ contain chemoreceptors

Tastants bind to chemoreceptors

102
Q

Chemical molecules in food bind to receptors leading to K+ closing–Depolarization

Are taste cells Neurons?

A

A BIG NO

Taste cell+Sensory neuron are required to convert chemical stimulus to nerve impulse

103
Q

4 taste qualities respond to specific receptors

What are these taste qualities and what do they respond to

A

Sweet(sugar)

Sour(Hydrogen H+ ion)

Salty(Na)

Bitter(toxic plant chemicals)

104
Q

Fun facts

Flavours are recognised mainly through the sense of smell

A

Taste cells and smell cells are the only sensory cells that are regularly replaced throughout a person’s life span.
Taste cells usually last a out 10 days

105
Q

What are odours detected by?

A

Olfactory receptor cells–Upper part of nasal passages.

106
Q

SMELL

what is the modified dendritic ending?

A

Branches to several olfactory hairs that extend into mucous covering of nasal passages.

Receptors for smell located on TRUE SENSORY NEURONS

107
Q

What is Olfaction?

When does it Occur?

A

Chemoreception that forms the sense of smell.
Has many purposes such as the detection of hazards, pheromones and food.

Occurs when odorants bind to specific sites on olfactory receptors located in the nasal cavity.

108
Q

How does olfaction occur?

A

Glomeruli aggregate signals from the olfactory receptors and transmit them to the olfactory bulb, where the sensory input will start to interact with parts of the brain 🧠🧠🧠 responsible for smell detection, memory and emotion.

109
Q

Smell

There are chemoreceptors for 1000’s odorant chemicals.

A

….

110
Q

What detects odours?

A

Olfactory receptor Cells

The upper part of nasal cavity.

111
Q

How are Gaseous and airborne odorants smelled?

A

Enter nasal passages and dissolve in mucous

Bind to chemoreceptors on Olfactory hairs to generate impulse.

Olfactory receptor Cells synapse with olfactory neurones in nearby olfactory bulb in brain.

112
Q

What are mechanoreceptors?

A

For special senses
Include::::::::

Hearing

Balance

113
Q

Hearing

What is the unit of sound

A

Sound is measured in decibels (dB)

0 dB is barely audible– it is the threshold of human hearing

114
Q

Hearing

How do we hear sounds?

A

The ear 👂 transduced sound waves into nerve impulses that brain 🧠 perceive as Sound.

There are hair cells that detect motion.

115
Q

The TONE is determined by frequency(Hz)

What is the range of tone/frequency can humans hear?

A

20-20 000 Hz

116
Q

SOUND

What determines Tone/Pitch?

A

FREQUENCY

117
Q

What determines Volume or loudness of sound?

A

AMPLITUDE OF SOUND WAVES.

118
Q

What is responsible for transducing sound waves into Neural signals(electrical impulses)?

🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓🤓

Believe you can and you will

And the Lord said “It is done”

A

AUDITORY APPARATUS.

KNOW THE LABELS

119
Q

The ear has 3 main Parts, namely the outer ear, the middle ear and the inner ear.
Explain the functions of each part of the ear..

A
  1. Outer 👂 Ear
    •Pinna and Auditory Canal
    •Sound channeled to tympanic membrane(also called the Eardrum)
  2. Middle 👂 Ear
    •Air filled chamber in temporal bone of Skull, bridges by 3 small bones.
    •Amplify sound
    • Kept at atmospheric pressure by auditory tube.
  3. Inner 👂 Ear
    èFluid filled
    èIt sorts and coverts sound
    √®Cochlea (sound converted) & Vestibular apparatus (✓ vestibule & 3 semicircular canals; balance)
120
Q

Hearing

What is the function of the Basilar Membrane?


What’s is the function of the organ of Corti ?🤸🤸🤸🤸🤸

Everything’s easy, as long as you put your whole mind into it. Love you Brother.

A

Sup ports 15 00l hair cells

The hair-like projection is embedded in TECTORIAL MEMBRANE.

THE organ of Corti converts pressure waves 🌊 to impulses.

Vibration of basilar Membrane causes hairs to bend. Movement of hair cells Opens ion channels and neurotransmitters to auditory nerve.

121
Q

MECHANORECEPTORS

BALANCE

What are the 3 semicircular canals responsible for?

Vestibule?

A

3 semicircular cans–Rotational movement

Vestibule–static position and Linear Acceleration.

•••√✓ Input from joint receptors, muse spindles & tendon receptors(also vision)+ Sense organ in the 👂 Ear=Integration of multiple sensory inputs.

122
Q

I KNOW IT ALL SEEMS TOO MUCH

BUT WE WILL MANAGE

A

And then God said,”It is done”

🤸🤸🤸♥️♥️♥️🤸🤸🤸♥️♥️♥️🤸🤸🤸♥️♥️♥️🤸🤸🤸♥️♥️♥️🤸🤸🤸♥️♥️♥️

123
Q

The vestibular system is the sensory apparatus of the inner ear that helps the body maintain its postural equilibrium

What are the 3 primary purposes of vestibular apparatus?

A
  1. They play a dominant role in the subjective sensation of motion and spatial orientation of the Head.
  2. Adjusts muscular activity and body position to maintain posture.
  3. Stabilizes in space the fixation point of the Eyes when the head moves, providing a stable image upon the Retina.
124
Q

Sensing Rotational Movement

What are the semicircular canals?

A

… complete

125
Q

Sensing Head position and acceleration

A

…complete this🥵

126
Q

Photoreceptors(•Special senses)
Vision
What is the function

A

¶ Light(Electromagnetic Radiation| 300 000m/s)

¶ Transduce light into Neural Impulses

¶ Retina of EYE- Collects Light.

¶✓ Photoreceptors- Receive and Process Visual Information.

The Retina is mostly studied in the CNS.

127
Q

The Retina has 4 layers

What are these layers?
Also name their functions.

A
  1. Pigmented cells&Choroid–Absorb light not captured by photoreceptor cells
  2. Rods&Cones- Photoreceptor cells, synapse with…
  3. Bipolar cells– Neuronal that synapse with layers of rods and cones, synapse with…
  4. Ganglion Cells– Also neuronal, long axons become optic nerves– integrate information
128
Q

What are Photoreceptors-?🤸🤸🤸

Please 🥺🙏 know the diagram associated with it.

A

These are divisible into Rods and Cones i.e. Rhodopsin(rods) and photopsins (cones)

(NB) Light passes through several layers of connecting neuronal before reaching the rods and cones.

Light is converted to Action Potentials.