ANAT 100 Mods 5-7 Flashcards
1
Q
What is the nervous system
A
- Is the body’s control and communication system
- controls voluntary and involuntary processes
2
Q
Three steps of the nervous system
A
Sensory input
Integration
Motor output
3
Q
Sensory input
A
Allows us to gather vital sensory information about our external environment (touch temp sound) and internal environment
4
Q
Integration
A
Create complete picture of environment incorporates multiple simultaneous signals
5
Q
Motor output
A
to produce an appropriate response by sending motor output signals through the motor nerves
6
Q
Two subdivisions of nervous system
A
Central nervous system
Peripheral nervous system
7
Q
Central nervous system
A
Made up of the brain and spinal cord, commonly referred to as the control center of the body
8
Q
Peripheral nervous system
A
Is composed of all the nerves outside of the brain and spinal cord
9
Q
Two principal cell types of the nervous system
A
Neurons and supporting cells
10
Q
Neurons
A
These cells are excitable and can generate and transmit rapid electrical signals to other neurons
11
Q
Direction of nerve impulses
A
It is unidirectional only occurring in one direction
12
Q
Neuron structure
A
Cell body
Cytoplasmic processes
- dendrites
- axons
13
Q
Neuron: cell body
A
Also called the soma and houses the nucleus and other organelles. Functions to transfer electrical signals from the dendrites to the axon
14
Q
Dendrites
A
Receive the neuronal signal from the other neurons and transfer those signals to the cell body
15
Q
Neuron: Axon
A
One per neuron carry the signal from the cell body to the axon terminal where signal is then transferred to other neurons or organs
16
Q
Classifications of neurons
A
Pseudounipolar (unipolar)
Bipolar
Multipolar
17
Q
Neurons: unipolar
A
Have one cellular process that splits into a dendrite and an axon
18
Q
Neuron: bipolar
A
Have one dendrite and an axon that extend directly from the cell body. Have two distinct cellular processes (only found in special sense like sight and hearing)
19
Q
Neuron: multipolar
A
Have multiple dendrites and one axon summing to three or more cellular processes. Most common type motor neurons
20
Q
Neurons: Supporting cells
A
Neuroglia, function to protect and support neurons as well as aid in sending signals between neurons to improve communication. But do not generate or transmit nerve impulses
21
Q
Four supporting cells of the CNS
A
Astrocytes
Microglia
Ependymal
Oligodendrocytes
22
Q
Astrocytes
A
Large star shaped cells with numerous processes. These cells communicate with neurons and blood vessels to maintain the integrity of the neural tissue. Most abundant glial cell in CNS
23
Q
Microglia
A
Small glial cells. Perform many protective functions in the CNS. They are able to phagocytose or engulf and destroy pathogens and eliminate waste products from the other cells. Are least common supporting cell
24
Q
Ependymal
A
Are cuboidal in shape and line cavities of the brain and spinal cord. These cells assist in the production, circulation and monitoring of CSF
25
Oligodendrocytes
Wrap around axons in the CNS to form myelin sheath
26
Myelination
Is composed mainly of fat and appears white. It insulates the axon and increase the speed at which electrical signals can travel down the axon
27
Support cell in PNS
Schwann cell
28
Schwann cell
Form myelin sheath around nerve fibers axons in the PNd
29
Schwann cell
Form myelin sheath around nerve fibers axons in the PNd
30
Parts of the brain
Cerebellum
Cerebrum
Brainstem
Midbrain
Pons
Medulla
Telencephalon
Diencephalon
31
Cerebellum
Is a structure that is appended to the back of the brainstem and sits underneath the occipital lobe of the cerebrum. Functions include motor activity
32
Brainstem
Is the area of the brain that connects the brain to the spinal cord.
33
Midbrain
Is the most superior aspect of the brain stem. Anteriorly the midbrain consist of large white matter that makes up the cerebral peduncles
34
Parts of the brainstem
Midbrain
Pons
Medulla oblongata
35
Pons
Is the structure in the middle of the middle stem. Located anterior to the 4th ventricle and cerebellum. Allows communications between the brain and spinal cord
36
Telencephalon
Is responsible for the interpreting sensory signals, sending out motor signals and decision making
37
Features of the telencephalon
Cerebral hemisphere
Cerebral cortex
Sulci and gyri
Lobes of the cerebrum
Grey matter
White matter
38
Cerebral hemispheres
Made up of two paired hemisphere right and left cerebral hemisphere separated by the longitudinal fissure
39
Sulci and gyri
Folded grooves increase surface area of neural tissue which increase the functional capacity of the tissue
40
Grey matter
Consists of the nerve bodies short interneurons and glial cells
41
Three categories of white matter
Association
Commissural
Projection fibres
42
White matter: association
Facilitate communication within one hemisphere
43
White matter: commissural
Facilitate communication between the two hemispheres
44
White matter: projection fibres
Facilities communication between different levels of the CNS such as between the brain and spinal cord
45
Meninges three connective tissue
Dura matter
Arachnoid matter
Pia matter
46
Dua matter
Most superficial and tough of the meninges composed of a double layer of connective tissue that attaches firmly to the skull
47
Arachnoid Mater
Loosely covers the brain creates an area called subarachnoid space. The space is filled with CSF and blood vessels
48
Pia matter
Is firmly attached to the cerebral cortex and is the innermost layer of the meninges
49
Ventricles of brain purpose
Provide support and protection to the brain contains CSF
50
Flow of CSF
Lateral ventricles
Inter-ventricular foramen
Third ventricle
Cerebral aqueduct
Fourth ventricle
Subarachnoid space
51
Spinal cord purpose
Facilitates communication between the central nervous system and the peripheral nervous system through the spinal nerves
52
The PNS- Sensory (afferent)
Transmits sensory info from the periphery to the CNS
53
The PNS- Motor (efferent)
Transmit motor commands from the CNS to the periphery
54
PNS- Somatic
Voluntary motor control of skeletal muscles
55
PNS- Autonomic
Involuntary motor control of smooth and cardiac muscle
Sympathetic and parasympathetic
56
12 cranial nerves
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Accessory
Hypoglossal
57
CN I: olfactory Nerve
Sensory only
Function: Smell
58
CN II: optical nerve
Sensory only
Function: vision
59
CN III: oculomotor nerve
Motor only
Function: movement of the eye
60
CN IV: trochlear nerve
Motor only
Function: movement of eye
61
CN V: trigeminal nerve
Sensory and motor
Function: muscle of medication chewing
62
CN VI: abducens
Motor only
Function: movement of eye
63
CN VII: facial nerve
Sensory and motor
Function sensory: anterior taste 2/3
Function motor: muscles of facial expression
64
CN VIII: vestibulocochlear
Sensory
Function: equilibrium and hearing
65
CN IX: glossopharyngeal
Sensory and motor
Function sensory: taste 1/3 of tongue
Function motor: pharynx muscle
66
CN X: vagus nerve
Sensory and motor
Sensory: innervation of larynx
Motor: pharynx and larynx muscles and thoracic and abdo organs
67
CN XI: accessory nerve
Motor
Functions: trapezius and stenocleidomastoid muscle
68
CN XII: hypoglossal
Motor
Function: muscles in tongue
69
Autonomic nervous system
Also known as visceral motor system and is responsible for transmitting involuntary signals from the CNS to smooth muscle, cardiac muscle and glands
70
ANS neuron pathways
Preganglionic
Postganglionic
71
ANS: preganglionic neruon
Has its cells body within the CNS, the axon enters into the PNS and travels to the autonomic ganglion
72
ANS: autonomic ganglion
Where the preganglionic and post ganglionic neurons meet and communicate located in the PNS
73
ANS: postganglionic
Is entirely in the PNS it’s cell body is in the autonomic ganglion while its axon travels to the target organ
74
Sympathetic nervous system: origin, response, effect
Original: spinal cord segment T1-L2
Response: fight or flight
Effect: widely distributed to many parts of body
75
ParaSympathetic nervous system: origin, response, effect
Original: Brainstem and spinal segment S2-S4
Response: rest and digest
Effect: more limited distribution to target organs
76
Spinal segment S2-S4 called
Craniosacral division
77
Spinal cord segment T1-L2 called
Thoracolumbar division
78
Sympathetic pathways
- Sympathetic preganglionic axons leave lateral horn of spinal cord
- pass through spinal nerve of the sympathetic trunk
Trunk provides a pathway for sympathetic fibres to travel through the body to effector tissue/organ
79
Parasympathetic pathways
- preganglionic neurons leave brain or spinal cord at level of sacrum
- pre meets post close to viscera
- postganglionic travel to effector organ
80
Nerves III, IV, IX supply
Head
81
Nerves X supply
Throax to descending colon
82
S 2.3.4 of vertebrae supply
Bladder and reproductive organs
83
Vision
Requires special visual receptors called photoreceptors located at the back of the eye
84
Accessory structures of the eye
Lacrimal gland, eyelid, extrinsic eye muscle
85
Lacrimal gland
Produces tears, which keep the cornea or outside surface of eyeball moist and clean
86
Eyelid
The upper eyelid contains the levator palpebrae superioris muscle and Orbicularis oculi muscle which control the opening and closing of the eyelid
87
Extrinsic eye muscle
There are six muscles that allow you to move your eyes to increase your range of motion
88
Six Extraocular eye muscles
Superior/inferior rectus
Medial/lateral rectus
Superior/inferior oblique
89
Cavities of the eye
Separated into two fluid filled cavities
Anterior cavity and posture cavity
90
Anterior cavity of the eye
Is composed of the anterior and posterior chambers both of which are filled with aqueous humour
91
Posterior cavity of eye
Compartment is filled with vitreous humour (gelatinous fluid)
92
Lens of the eye
Separates the anterior and posterior cavity of the eye
93
Layers of the eye
Outer layer- fibrous
Middle layer- vascular
Deep layer- sensory
94
Middle layer of eye made up of
Choroid
Ciliary body
Iris
95
Choroid of eye
Contains the blood vessels that supply the eye with oxygen and nourishment
96
Ciliary body of the eye
Produces aqueous humor and contains the ciliary muscles which control the shape of the lens
97
Iris of the eye
Contains the sphincter and dilator muscles which control the narrowing and widening of the pupil
98
Deep layer of the eye contains
Sensory tunic innermost layer of eye
Neural layer
Optic disc
Macula
CN II nerve
99
Neural layer of eye
Outermost region made up of photoreceptors (robs and cons) which are light sensitive cells
100
Optic disc of eye
Is the area where smaller nerve cell axons converge. It is the location we can see when we look into the eye
101
Macula of the eye
Is the central area of the retina the central depression of the macular are where fine detailed vision occurs
102
Outer layer of the eye consist of
The fibrous tunic is the outermost layer
Sclera
Cornea
103
Sclera of the eye
Is the internal aspect of the fibrous tunic located posterior to the lens. Form the white portion of the eye
104
Cornea of the eye
Is the external aspect of the fibrous tunic located anterior to the lens. It transparent enabling light transmission
105
Flow of aqueous humour
1. Produced by ciliary in posterior chamber
2. Flows through the pupil into anterior chamber
3. Exits anterior chamber angle through trabecular Westwood
4. Arriving at schlemms canal
5. Then into episcleral venous channels
106
The ear is divided into these three sections
External ear
Middle ear
Inner ear
107
External ear
Represents structures of ear you can touch.
Sound waves travel through external auditory canal to reach the tympanic membrane causing vibration
108
Ceruminous gland of ear
Are microscipic glands that are present in the external auditory canal these secrete ear wax
109
Middle ear
Located within the temporal bone.
Sound waves involved with hearing are also transmitted through the middle ear
110
Three bones of the middle ear
Malleus (hammer)
Incus (anvil)
Stapes (stirrup)
111
Inner ear
Located within the temporal bone
It house receptors responsible for hearing and equilibrium
112
Inner ear components
Vestibular apparatus
Cochlea
113
Vestibular apparatus of ear
Contains receptors for equilibrium made up of three parts
114
Cochlea of ear
Contains receptors for hearing looks like a seashell
115
Vestibular apparatus three structures
Semicircular canals
Utricle
Saccule
116
Semicircular of ear
Detects rotational movement aka changes in the head position such as side to side and up and down
117
Utricle and saccule of ear
Are responsible for detecting positional movement aka respect to gravity and linear acceleration
118
Three ducts of the cochlea
Vestibular
Tympanic
Cochlear duct
119
Organ of corti of ear
Is made up of specialized cochlear hair cells when the membrane is moved by sound waves the hair cells fire impulse which is sent to the brain
120
Endocrine
Cells of these glands secrete hormones directly into the interstitial surrounding the secretory cells. Hormone are then picked up by the blood capillaries
121
Exocrine
Glands secrete cell products into a duct system
122
Hormones
Act as chemical messengers travelling through the blood circulation to cause an effect on a target organ
123
Endocrine glands (5 types)
Pituitary gland
Thyroid gland
Parathyroid gland
Adrenal gland
Pancreas
124
Pituitary gland
Small pea size gland at the base of the brain that extends from the hypothalamus. It is known as the master gland as it produces and release hormones that control all other endocrine glands
125
Thyroid gland
Sits anterior to the trachea and produces thyroid hormones important for metabolism. It is also involved in calcium homeostasis
126
Adrenal gland
Sits on top of each kidney. They have important roles in the production of corticosteroids as well as the maintenance of fluids
127
Corticosteroids
Group of steroid hormones produced by the cortex of the adrenal gland that are responsible for several functions such as glucose metabolism sex characteristics and electrolyte balance
128
Pancreas
Is both an endocrine and exocrine gland. Located posterior to the stomach extending from the duodenum to the spleen. It’s main endocrine function is to control sugar levels in blood
129
Pituitary gland divided into two lobes
Anterior lobe
Posterior lobe
130
Pituitary Anterior lobe six hormones
TSH
PRL
ACTH
GH
FSH and LH
MSH
131
TSH
Thyroid stimulating hormone: acts on the lid gland causing it to release thyroid hormones
132
PRL
Prolactin: induces the mammary glands of the breast to produce milk
133
ACTH
Adrenocorticotropic hormone: acts in the adrenal glands causing them to release their hormones. Regulate blood pressure, blood sugar
134
GH
Growth hormone: growth in all cells
135
FSH
Follicle stimulating hormone: acts in the gonads stimulate secretion of estrogen and progesterone and maturation of oocytes in the ovaries
136
LH
Luteinizing hormone: acts on gonads in males, they stimulate secretion of testosterone and sperm production in testes
137
MSH
Melanocyte stimulating hormone: simulates melanocytes in the skin to produce pigment
138
Portier lobe of pituitary gland two hormones
Antidiuretic hormone
Oxytocin
139
Antidiuretic hormone
Promote reabsorption of water at the kidneys
140
Oxytocin
Promote uterine contractions during childbirth plays role in breasting feeding as well as
141
Pituitary anterior lobe tissue
Glandular tissue
142
Pituitary gland posterior lobe tissue
Nervous tissue
143
Thyroid gland three structures
The right lobe
The left lobe
Isthmus
144
Colloid
A protein rich fluid secreted by the follicular cells
145
Follicular cells
Are simple cuboidal cells surrounding each follicle. Producing triiodothyronine and thyroxine which increase the rate of metabolism and oxygen consumption
146
C cells
Are important in calcium homeostasis they produce calcitonin a hormone which lowers the blood calcium concentration
147
Adrenal glands divisions
Medulla
Cortex
148
Adrenal gland layers
The outer layer
The middle layer
The inner layer
149
Adrenal gland outer layer
Produces mineralocoeticoids
150
Adrenal gland middle layer
Produces glucocorticoids
151
Adrenal gland inner layer
Produces androgens (sex hormones)
152
Adrenal gland medulla
Is the core of the adrenal gland it produces epinephrine and norepinephrine in the response to sympathetic nervous system stimulation resulting in an autonomic right or flight response
153
Endocrine cells of the pancreas
Islet of lanergans
Alpha and beta
154
Beta cells of pancreas
Produce the hormone insulin which functions to lower blood glucose levels
155
Alpha cells of pancreas
Produce glucagon functions to increase blood glucose levels
