LO4 Notes- Nervous System Flashcards
1
Q
What are the 3 general functions of the nervous system?
A
- Sensory function (temp,pain, senses) 2. Integrative function (signals create perception) 3. motor function (move muscles and helps maintain homeostasis)
2
Q
2 STRUCTURAL divisions of Nervous system
A
Central NS and Peripheral NS
3
Q
How many cranial nerves are there?
A
12 pairs (from the brain)
4
Q
How many spinal nerves are there?
A
31 pairs (arise from spinal cord)
5
Q
2 FUNCTIONAL divisions of NS
A
Voluntary (Somatic), conscious control of muscles, sensations from skin to brain. and Involuntary (Autonomic)- unconscious control of cardiac and smooth muscle and glands
6
Q
2 divisions of autonomic nervous system
A
Sympathetic (fight or flight) and Parasympathetic (rest and digest)
7
Q
What are neurons?
A
Basic cells of nervous system, specialized to respond to stimulus and conduct impulse
8
Q
What are dendrites?
A
specialized fibres that function as receptive surfaces that receive a stimulus
9
Q
What is the cell body?
A
contains nucleus and cell organelles and can function as a receptor site
10
Q
What is an axon?
A
only one per neuron, it transmits the impulse to another neuron, muscle or gland. Ends with a synaptic knob that releases NT’s at synapse
11
Q
What is myelin? And what is difference between myelinated and unmyelinated axons?
A
Myelin is lipid rich compound that can cover axons. They speed up rate of transmission. Myelinated axons= white matter, Unmyelinated axons=grey matter
12
Q
3 types of neurons
A
Sensory (Afferent)-carry from body parts to brain and spinal cord, Motor (Efferent)- from brain and spinal cord to effectors which are muscles or glands, and Interneuron (Association)- form links between neurons in brain and spinal cord
13
Q
How to remember sensory vs. motor
A
SAME (Sensory Afferent Motor Efferent)
14
Q
What is a neuroglial cell?
A
“Nerve glue”- functions to fill spaces, support neurons, produce myelin, provide structure, and carries out phagocytosis
15
Q
What is basic description of synaptic transmission?
A
Impulse sent from presynaptic neuron down axon, across synaptic cleft, to dendrites of postsynaptic neuron. Neurotransmitters are released into synaptic cleft which is chemical that allows message to cross the small gap
16
Q
Where does synaptic transmission occur?
A
Only in grey matter of brain and spinal cord. It is slower and needs to be cleaned up after transmission so only happens there. Synapses, where a nerve stimulates a nerve, occur only in the grey matter of the brain and spinal cord. All decisions, thinking etc., occur in grey matter
17
Q
What happens in white matter?
A
“wiring” of brain and spinal cord. Transmission of impulses that is much faster than synaptic transmission. White matter of the brain and spinal cord is for transmission of neural impulses only (is just wiring) connecting a to b.
18
Q
What is the cerebrum?
A
Largest part of the brain, 2 halves connected by corpus callosum, is involved in all conscious activities
19
Q
What are the different folds of the cerebrum called?
A
The folds are gyri, shallow grooves are sulci, and deep grooves are fissures
20
Q
What are sensory areas?
A
Where sensory stimuli is received; sensations are created and then projected back to point of origin
21
Q
What are the sensory areas and where are they located?
A
Auditory in temporal lobes, visual in occipital lobes, general sensation (hot, cold, pain, touch) in parietal lobes
22
Q
What are motor areas? Where are they found?
A
They control skeletal muscles. Primary motor area controls all skeletal muscles- found in frontal lobes. Motor speech area- controls muscles of speech and is only found in left frontal lobe (Broca’s area)
23
Q
What are association areas?
A
Found in all sensory areas, work to associate new stimuli/experiences with existing ones
24
Q
What is the cerebral cortex?
A
AKA “grey matter”, outer layer of cerebrum, contains only interneurons where most synapses occur
25
What is white matter?
neurons are myelinated which makes them white and increases the speed of transmission and they carry info from point A to point B
26
What does the diencephalon include?
The thalamus and hypothalamus
27
What does the thalamus do?
"Thelma the switchboard operator"- provides nonspecific awareness of sensations as they pass through. Receives and relays all sensory info except smell (olfactory)
28
What does hypothalamus do?
Important in maintaining homeostasis. Controls autonomic nervous system (all involuntary organ activities- heart, BP, intestine movement, urination, etc.). Senses body changes and creates response to correct change- like temp, water levels, blood glucose. Centre for our primitive emotions like rage and fear. AND regulates sleep wake cycle
29
What is cerebellum?
At back of skull under occipital lobes of cerebrum. It controls posture, equilibrium and coordination and helps keep us upright
30
What is the brain stem?
Contains midbrain, pons, and medulla oblongata
31
What do midbrain and pons do?
They have pathways for ascending (sensory) impulses/tracts and pathways for descending (motor) impulses/tracts. They contain some reflex centres- pons assists in breath control
32
What does medulla oblongata do?
It contains vital reflex centres for heart rate, breathing rate, and blood pressure and lesser reflexes like sneezing, coughing, vomiting, and swallowing
33
Features of spinal cord
has 31 segments- 31 pairs of spinal nerves which exit from the 31 segments. Has a moth shaped grey matter interior where most neurons synapse with each other and the grey matter is surrounded with white matter. Ascending sensory tracts up to thalamus and descending to muscles and glands
34
What are meninges?
They function to protect, support, and nourish the brain and spinal cord. -has 3 layers
35
What are the 3 layers of the meninges?
Dura Mater (outer)- "tough mother", strong, anchored to brain, helps protect skull. Arachnoid mater (middle)- "spider like" web- contains CSF and acts as shock absorber and waste remover. Pia Mater (inner)- "delicate mother"- thin and "shrink wrapped" to surface of brain and spinal cord. Contains many blood vessels to nourish brain and spinal cord
36
What is a reflex arc?
a 5- component pathway from receptor to effector. 1. receptor senses stimulus. 2. sensory neuron carries impulse to CNS. 3. Interneuron integrates message "Thinking part" 4. motor neuron carries message to effector. 5. Effector- muscle or gland that is stimulated
37
How many pairs of cranial nerves are there?
12
38
How many pairs of spinal nerves are there?
31
39
What are features of somatic nervous system?
"Stick shift", uses 1 motor neuron, conscious control of skeletal muscles, sensations travel from skin to brain
40
What are features of autonomic nervous system?
Automatic, unconscious control of cardiac muscle, smooth muscle, and glands, uses 2 motor neurons, divided into parasymp and sympathetic NS
41
Where does phrenic nerve go?
To diaphragm
42
Where do radial and ulnar nerves go?
To the arm
43
Where does sciatic nerve go?
To the posterior leg and back of leg
44
Which spinal nerve goes to diaphragm?
The phrenic nerve
45
Which spinal nerve goes to the arm?
The radial and ulnar nerves
46
Which spinal nerve goes to posterior leg and back of leg?
The sciatic nerve
47
What are the names of the first four cranial nerves?
On Occasion Our Trusty Truck Acts Funny, Very Good Vehicle Any How. On Occasion Our Trusty: I-Olfactory: sense of smell II- Optic: vision III- Oculomotor: moves eyelids and eyeballs and constriction of pupils IV- Trochlear: moves eyeball
48
What is the name of the 5th cranial nerve and its branches?
On Occasion Our Trusty Truck Acts Funny, Very Good Vehicle Any How. TRUCK- V- Trigeminal: 3 sensory branches: Ophthalmic (V1)-transmits impulses from forehead region around eye and scalp. Maxillary (V2)- transmits impulses from upper teeth and associated tissue eg. lip, palate and skin of face. Mandibular (V3)- transmits impulses from lower teeth and gums, lips, cheeks. The motor function is to transmit impluses to muscles of mastication
49
What are the names of cranial nerves 6 and 7?
On Occasion Our Trusty Truck Acts Funny, Very Good Vehicle Any How. ACTS FUNNY. VI- Abducens: Moves eyeball. VII- Facial. Facial nerve has sensory function of taste for anterior 2/3 of tongue and has motor function by stimulating muscles of facial expression and stimulation of secretions from glands
50
What are the names of cranial nerves 8, and 9?
On Occasion Our Trusty Truck Acts Funny, Very Good Vehicle Any How. VERY GOOD. VIII- Vestibulocochlear (Acoustic) (vestibular branch for balance from inner ear and cochlear branch for hearing). IX- Glossopharyngeal (sensory function transmits taste impulses from posterior 1/3 of tongue and motor function stimulates muscles of pharynx for swallowing and stims secretions from parotid salivary gland)
51
What is the name of cranial nerve 10?
On Occasion Our Trusty Truck Acts Funny, Very Good Vehicle Any How. VEHICLE. X- Vagus. Motor functions are to transmit impulses to all organs in thoracic and abdo cavities... slows heart rate and increases digestive movements. Sensory functions to transmit pain impulses from visceral organs of thorax and abdomen
52
What are the names of cranial nerves 11 and 12?
On Occasion Our Trusty Truck Acts Funny, Very Good Vehicle Any How. ANY HOW. XI- Accessory: moves some muscles of head and neck (Trapezius and SCM). XII- Hypoglossal: Stimulates muscles that move the tongue.
53
How to remember the functions of each cranial nerve?
Some Say Mind Matters, But My Brother Says Big Bucks Matter Most. where S is sensory, M is motor and B is both
54
What are the four parasympathetic cranial nerves?
FOG in Vagus. Facial, Oculomotor, Glossopharyngeal, and Vagus
55
What is sensation?
"feeling" that occurs when brain interprets a sensory impulse and the sensory receptors reach threshold
56
What is perception?
Sensory impulses travelling to brain are all the same and brain is able to interpret and identify each sensation
57
What is projection?
When sensation forms, the cerebral cortex causes the feeling to seem to come from the stimulated receptors and the brain projects the sensation back to its apparent source
58
What is adaptation?
Ability of the nervous system to become less responsive to a maintained stimulus and occurs when the same stimulus repeatedly stimulates a receptor
59
What is referred pain?
Visceral pain that may feel as if its coming from a part of the body other than the part being stimulated. eg. a heart attack may feel like pain in shoulder
60
Gustation. Where are receptors, what is the sensory pathway, and where is the sensory area in the brain?
Receptors: taste buds on anterior tongue. Sensory pathway is through facial nerve for anterior tongue and glossopharyngeal nerve for posterior tongue. Sensory area is in parietal lobe by way of thalamus 1st
61
Olfaction. Where are receptors, what is the sensory pathway, and where is the sensory area in the brain?
Receptors: olfactory cells. Pathway is olfactory nerve. Sensory area is olfactory area in temporal and frontal lobe. DOES NOT pass through thalamus
62
What is the sclera?
The white of the eye
63
What is the cornea?
Transparent and allows light to enter eye, "window"
64
What is choroid?
Contains the dark pigment melanin and absorbs stray light rays which prevent reflection and scattering of light within the eyeball
65
What is the iris?
The pigmented part of eye, controls size of pupil and amount of light entering eye
66
What is the lens?
behind the pupil, transparent and changes shape to accommodate for near and far vision and helps focus
67
What is the retina?
Contains 2 types of photoreceptors: rods and cones
68
What is optic disk?
"blind spot" with no photoreceptors bc its where optic nerve leaves back of eye
69
What is difference between rods and cones?
Rods capture grey shades in low light and cones capture colours in bright light
70
What is the aqueous humour?
Watery anterior chamber in front of lens that is continuously secreted and replaced
71
What is the vitreous humour?
Jelly-like posterior chamber behind lens that maintains shape of eye
72
What is the middle ear?
located in temporal bone, air filled space has opening for eustachian tube and contains the auditory ossicles (malleus, incus, stapes)
73
Which bone vibrates the oval window?
The stapes
74
What is the vestibule?
Contains mechanoreceptors for STATIC equilibrium "Sense of gravity"
75
What are the semicircular canals?
Contains mechanoreceptors for DYNAMIC equilibrium; the receptors are activated when speed or direction of movement of your head changes
76
What is the cochlea?
Contains the spiral organ (Organ of Corti) and is location of hair cell receptors for hearing
77
What is an endocrine gland?
They are ductless and secrete hormones directly into blood or body fluids
78
What are the two main classes of hormones?
Steroids (made from cholesterol) and non-steroids (made from amino acids)
79
What are the features of steroid hormones?
lipid soluble and can pass through cell membranes, receptors are located on target cell and activate production of specific proteins
80
What are features of non-steroid hormones?
Water soluble, cannot penetrate plasma membrane, combine with receptors on target cell membranes, trigger cascade of biological activity
81
What are the 6 hormones secreted by the anterior pituitary gland?
Growth hormone, Prolactin, Thyroid Stimulating Hormone, Adrenocorticotropic Hormone, Luteinizing Hormone, and Follicle Stimulating Hormone
82
Which two hormones are stored in and released from the posterior pituitary gland?
Antidiuretic hormone and Oxytocin
83
Which hormone targets body cells and stimulated them to increase in size and reproduce more quickly?
Growth Hormone
84
Which hormone stimulates milk production by targeting the mammary glands?
Prolactin
85
Which hormone stimulates secretion of thyroxine by targeting the thyroid gland?
Thyroid Stimulating Hormone
86
Which hormone stimulates secretion of glucocorticoids (cortisol) by targeting the adrenal cortex?
Adrenocorticotropic Hormone
87
Which hormone stimulates ovulation in the female ovaries and stimulates secretion of testosterone in male testes?
Luteinizing hormone
88
Which hormone stimulates sperm and egg production in the ovaries and testes?
Follicle Stimulating Hormone
89
Which hormone targets the kidneys and causes them to conserve water and decrease urine production?
Antidiuretic Hormone
90
Which hormone targets the smooth muscles of the uterine wall and causes contraction of the uterus in labor and the "let down reflex" of milk release.. aka the emotional bonding hormone?
Oxytocin
91
which hormones do the thyroid gland produce?
Thyroxine (T4) and T3
92
What do the thyroid hormones do?
They increase the rate of cell metabolism and increases the rate of energy production. Synthesis requires iodine
93
What does calcitonin do and what cells does it target?
Decreases blood calcium levels by adding it to bone. Targets osteoblasts in bones
94
Where is calcitonin made?
In the thyroid
95
What does parathyroid hormone do and what cells does it target?
Functions to increase blood calcium concentration by removing it from bone. Stimulates osteoclasts in bone to result in bone reabsorption and calcium released in blood.
96
What are the two pancreatic hormones?
Insulin and Glucagon
97
What are the two parts of the adrenal glands?
Adrenal cortex and adrenal medulla
98
What are the hormones of the adrenal cortex?
Cortisol and Aldosterone
99
What does cortisol do?
Targets liver, It is anti-inflammatory and is released in response to conditions that stress the body. Requires greater supply of energy and stims energy production from proteins and fats, not carbs
100
What does aldosterone do?
targets kidneys, helps regulate electrolyte concentration. Causes kidneys to conserve sodium and therefore water and excrete potassium
101
What is the hormone of the adrenal medulla?
Epinephrine
102
What does epinephrine do?
Secreted directly in blood stream. Release stimulated by nerve impulses. Released in times of stress for fight or flight.
103
What hormones do the ovaries produce?
Estrogen and Progesterone
104
What does estrogen do?
Targets all body cells and functions to develop secondary sex characteristics like breasts, pubic hair, menstruation, fat deposition
105
What does progesterone do?
Development of uterine lining
106
What is function of testes?
Produce testosterone and development of male secondary sex characteristics- muscle and skeletal development, deeper voice, aggression, and facial/pubic hair growth
107
What is the thymus gland?
It secretes thymosin and targets lymphocytes--> T cells specifically. Causes maturation of lymphocytes for immunity
108
What is the pineal gland?
Secretes melatonin and targets the brain, functions to regulate the circadian rhythms and promotes sleep
109
What is normal pH of blood?
7.35-7.45- slightly alkaline
110
What is most abundant plasma protein?
Albumin
111
What does fibrinogen do?
Key role in blood clotting
112
What do globulins do?
Transport lipids and fat-soluble vitamins and have role in immunity'
113
what is hematocrit?
cellular portion of blood made of erythrocytes (red blood cells)
114
What is buffy coat?
about 1% of blood sample made of leukocytes (white blood cells) and thrombocytes (platelets)
115
Which blood cells have no nucleus so they can carry more hemoglobin?
Erythrocytes (red blood cells)
116
Which nutrients are needed for RBC synthesis?
Vitamin B12, Folic acid, and Iron
117
What are the 3 stages of hemostasis?
1. Vascular Spasm 2. Platelet plug formation 3. Coagulation
118
What happens in vascular spasm?
Constriction of blood vessel to limit blood loss- temporary but gives time for platelet plug formation
119
What happens in platelet plug formation?
Platelets stick to any rough surface so they stick to each other and then shrink to pull walls of vessel together
120
What are the 3 stages of coagulation?
1. substances released at injury site results in activation of prothrombin activator. 2. prothrombin activator and calcium convert prothrombin to thrombin. 3. thrombin and calcium convert fibrinogen to fibrin. Fibrin is a sticky thread that crisscrosses the break
121
What is an antigen?
Proteins located on cell membranes of RBC's. Like little flags that can activate the immune . 2 groups are ABO group and Rh factor
122
What are antibodies?
Dissolved in plasma, react to certain antigens. Blood plasma always contains antibodies to the antigens NOT present on the red blood cells
123
Which part of the heart is the base?
The superior (top) part
124
Which part of heart is the apex?
The inferior (bottom) part. Points downward to left and rests on diaphragm
125
What is the pericardium?
The fibrous pericardium is the outermost bag layer and the parietal pericardium is the inner layer that folds back on itself to become the visceral pericardium (aka epicardium). In between is the pericardial cavity filled with serous fluid
126
What is the myocardium?
The middle layer composed of cardiac muscle (pumps the blood)
127
What is the endocardium?
The inner lining of the heart. Forms vales and is continuous with lining of blood vessels (so don't have clotting problems)
128
Which sides of the heart deal with oxygenated vs. deoxygenated blood?
LORD- Left Oxygenated Right Deoxygenated
129
What are the names of the atrioventricular valves?
Right AV valve is tricuspid and Left AV valve is bicuspid (mitral) valve
130
What is function of AV valves and how are they anchored?
Function to prevent backflow of blood. They are anchored by chordae tendinae to papillary muscles of heart wall
131
Where are the AV valves located?
Between the atriums and ventricles. So left AV valve is between the left atrium and left ventricle
132
What are the semilunar valves?
They are between the ventricles and the great blood vessels. Names of them are the pulmonary valve and the aortic valve
133
Where is the pulmonary valve located?
Between the right ventricle and the pulmonary trunk
134
Where is the aortic valve located?
Between the left ventricle and the aorta
135
What is the septum?
The wall between the right and left sides of the heart
136
What is the interatrial septum?
The wall between the two atria
137
What is the interventricular septum?
The wall between ventricles
138
What is the fossa ovalis?
A small depression that is a remnant of the foramen ovale. This was an opening between the atria in fetal hearts to allow blood to bypass the lungs in utero
139
Describe the pathway of the pulmonary circuit
The right atrium receives deoxygenated blood from the body and the right ventricle pumps deoxygenated blood to the lungs
140
Describe the pathway of the systemic circuit
The left atrium receives oxygenated blood from the lungs and the left ventricle pumps it to the body.
141
What is the thickest muscle of the heart?
The left ventricle. Needs to be strong to pump blood to the whole body
142
What is contraction of heart called?
Systole
143
What is relaxation of heart called?
Diastole
144
Try to name the order of blood thru the heart starting with deoxygenated blood from body
Deoxy blood enters from superior and inferior vena cava and coronary sinus--> into right atrium --> tricuspid valve--> right ventricle--> pulmonary valve--> pulmonary trunk--> to lungs. Then oxygenated blood goes through pulmonary veins--> left atrium--> bicuspid valve--> left ventricle--> aortic valve--> aorta
145
Which blood vessel type remains open when not filled with blood and carries blood away from heart under high pressure?
Arteries
146
Which blood vessel is smaller and leads from an artery into a capillary?
Arterioles
147
Which blood vessel is microscopic, only one cell thick, and allows for exchange of gases, nutrients, and wastes?
Capillaries
148
Which vessel leads from a capillary into a vein?
Venules
149
Which vessel carries blood under relatively low pressure toward the heart, has valves, and collapses when not filled with blood?
Veins
150
What is the circulatory pathway from ventricles back to atrium (involving the arteries, capillaries, and veins)?
Eg. Right ventricle--> pulmonary trunk--> right and left pulmonary arteries--> pulmonary capillaries in lungs (site of gas exchange)--> pulmonary veins--> left atrium of heart
151
What is the order of the coronary circulation from left ventricle to right atrium?
left ventricle-- aorta-- coronary arteries-- myocardial capillaries-- cardiac veins-- coronary sinus-- right atrium of heart
152
What is the largest artery in the body?
Aorta
