Unit 3 Flashcards
1
Q
Role of Muscle Tissues (3)
A
- generate force
- generate movement (internally; move blood, waste, bones, etc.)
- generate heat (biochemical)
2
Q
Properties of Muscle Tissue (5)
A
- Excitability
- Contractility
- Extensibility
- Elasticity
- Adaptability
3
Q
Excitability
A
the ability to respond to stimulation (stimulus)
4
Q
Contractility
A
the ability to shorten actively and exert a pull or tension that can be harnessed by connective tissues (response)
5
Q
Extensibility
A
the ability to continue or contract over a range of resting lengths
6
Q
Elasticity
A
the ability of a muscle to rebound toward its original length after a contraction
7
Q
Adaptability
A
muscles will change in response to patterns in use (hypertrophy and atrophy - use it or lose it)
8
Q
Muscle Types (3)
A
- striated skeletal
- cardiac
- smooth (internal organs)
9
Q
Skeletal Muscle
A
- has striated appearance (indicate tight compact of myofilaments)
- multiple nuclei
- has fibers (=cells) 10-100um in diameter and lengths 100mm-1m
- myofilaments must be aligned in the muscles for contraction
10
Q
Muscle Organization (smallest to largest)
A
muscle fiber > muscle fascicle > skeletal muscle
11
Q
myo-
A
“muscle”
12
Q
Myofibrils (=microfilaments)
A
- contractile proteins
- regulatory proteins (mediate contraction)
- accessory proteins (maintain alignment)
13
Q
Contractile Proteins
A
- myosin
- actin
14
Q
Myosin
A
- composes “thick” filaments
- consists of 2 intertwined heavy chains
- has bulbous “head” at extremes (fitted with hinge for swiveling)
15
Q
Actin
A
- composes “thin” filaments
- consists of polymerized globular proteins
- includes paired, twisted actin polymers
16
Q
Sarcomeres
A
- have crossbridges
- give rise to striations
- connect between actin and myosin
17
Q
In the crossbridges…
A
- the A band does not change in distance
- when ATP binds, “actin slides over myosin”
- the I band and H zone shortens
18
Q
Titin…
A
- provides elasticity and stabilizes myosin
- largest known protein
19
Q
Nebulin…
A
- helps align actin
- makes sure actin slides in 1 plane
- makes sure actin is in correct position for myosin to bind (IMPORTANT)
- no nebulin can cause muscle paralysis
20
Q
Muscle Contraction (simplified - 4 steps)
A
Chemical signal > electrical signals > Ca2+ signals > Excitation > Contraction/relaxation cycle
21
Q
The Power Stroke
A
- Myosin heads bind actin filaments (bind to single monomer - specific)
- crossbridges push filaments inward
- myosin heads release actin filaments
- myosin heads bind NEW actin molecules
- must have control over power stroke
22
Q
Tropomyosin
A
- is an elongated protein
- blocks myosin-binding sites (partially)
- allows weak actin-myosin binding
(resting position is blocking interaction)
23
Q
Troponin
A
- controls position of tropomyosin
- binds calcium reversibly
24
Q
2 Regulatory Proteins for Protein Contraction
A
- Tropomyosin
- Troponin
25
Contraction Regulation
1. Increase cytosolic calcium
2. Binds
3. Tropomyosin shifts, exposing binding site on G-actin
4. Power Stroke
5. G-actin moves
26
Sarcomeres contain...
thick and thin filaments
27
Myofibrils are surrounded by...
sarcoplasmic reticulum that stores calcium
28
Muscle fibers are surrounded by...
endomysium
29
Muscle fascicles are surrounded by...
perimysium
30
Skeletal muscle is surrounded by...
epimysium
31
Properties of muscles and of the muscular system
- muscles have directionality (must pull in same plane and must be aligned; stretching)
-muscles work in antagonistic pairs for every plane of movement
32
Muscles must work in groups
- must engage large groups simultaneously
- use many muscles to actually function
33
Types of Skeletal Muscle Fibers (2)
1. Fast (White) Fibers
2. Slow (Red) Fibers
34
Fast (White) Fibers
- are larger in diameter - due to many densely packed myofibrils
- have low glycogen, low mitochondria
- fatigue easily
- can contract in 0.01 sec or less following stimulation
- minimal lag time - reflexes = white fibers
35
Slow (Red) Fibers
- 1/2 diameter of fast fibers
- more glycogen, more mitochondria, more myoglobin
- fatigue slowly
- contract 0.03-0.05 sec after stimulation (slower)
36
Force ____ as cross-sectional area ____.
increases, increases
37
Fascicle Orientations
- parallel
- bipennate
- multipennate
- circular
- convergent
38
Parallel
- give most range of motion
- least amount of force
- limited repetition
39
Bipennate
pennate - at an angle
- increases force
- less range of motion
40
Muscles - Supportive Structures
- tendons
- fascia
41
Tendons
- attach muscles to bones
- high tensile strength in same plane of contraction (soft tissue)
- lots of collagen
- composite nature gives it strength
42
Tendonitis
- inflammation of the tendon
- caused by:
overuse
impact
more common while growing
43
Fascia
- attach muscles to other muscles
- dermis to muscle connection
- not meant to endure strain
- is a network to hold things (muscles) in place
44
Dr. K's 5 Golden Rules of Skeletal Muscle Movement
1. All skeletal muscles cross at least one joint
2. The bulk of skeletal muscles lies proximal to the joint crossed
3. All skeletal muscles have at least 2 attachment points (origin and insertion)
4. Skeletal muscles PULL; they cannot/do not push
5. During contraction, the point of insertion moves toward the point of origin
EXCEPTIONS: lips and hands
45
Muscle Activity and Body Movement
- movement results when a muscle moves an attached bone
- 2 attachment points: origin and insertion
46
Origin
attachment to immoveable bone
47
Insertion
attachment to moveable bone
48
Types of Muscle Contraction
1. Concentric
2. Static or Isometric
3. Eccentric
49
Concentric Contraction
- length of muscle shortens
- muscle force is greater than the resistance
"the weight will move because the muscle can generate more force than the weight"
50
Static or Isometric Contraction
- no change in muscle length
- muscle force is equal to the resistance
"the weight will not move"
51
Eccentric Contraction
- muscle lengthens
- muscle force is less than resistance
"putting the weight down or the weight has more force than the muscle can generate"
52
Role of Muscle
- agonist (bicep pulling up/tricep pulling down)
- antagonist (tricep relaxes/bicep relaxes)
(see Dr. K's chart in notes)
53
Agonist
- prime mover
- provides the major force to complete the movement
54
Antagonist
- action opposes the agonist
55
Major Muscle Regions (7)
1. arms
2. shoulders
3. back
4. chest
5. abdominals
6. legs
7. calves
56
Arm Muscles (2)
1. biceps brachii
2. triceps brachii
57
Biceps Brachii
- 2 heads
- parallel fibers
- prime mover for flexion of the forearm
- acts to supinate the forearm
- the antagonist for triceps brachii
58
Triceps Brachii
- parallel fibers
- prime mover of elbow extension
- antagonist of biceps brachii
59
Shoulders (Deltoids)
- triangular
- multipennate muscles that form the rounded shape of the shoulders
- the prime movers of abduction
60
Trapezius
- the most superficial muscles of the posterior neck and upper trunk
- extend the head
- elevate, depress, adduct, and stabilize the scapula
61
Back Muscles
1. Trapezius
2. Latissimus Dorsi
62
Latissimus Dorsi
- paired large, flat muscles
- with convergent fascicle arrangement that cover the lower back and flank
- assists in depression of the arm
- adducts, extends, and internally rotates the shoulder
- attaches to thoracic, lumbar, and illium
63
Pectoralis Major (Chest)
- large fan shaped convergent muscles
- cover the upper part of the chest and anterior wall of the axilla
- adduct and flexes the arm
- 3 regions that work together
(lift arm from your side)
64
Abdominals
1. Rectus Abdominus
2. External Obliques
65
Rectus Abdominus
- the most superficial muscles of the abdomen
- responsible for trunk flexion, forced expiration
- can work different parts with different exercises
66
External Obliques
- muscles with parallel fascicle orientation that forms the superficial lateral abdominal wall
- flex the trunk, assist expiration by depressing the ribs
- supports intra-abdominal viscera
- attaches to pubis
- can be part of groin and back pain
67
Legs
Anterior Surface
- sartorius
- quadriceps
- gracilis
Posterior Surface
- hamstring
68
Sartorius
- largest muscle we have
- from illiac crest to tibia
- extends the hip and extends/laterally rotates the knee
- inserts on tibia
69
Quadriceps
4 parallel muscles
- rectus femoris
- vastus lateralis
- vastus medialis
- vastus intermedius
extends the leg at the knee joint
flexed the thigh at hip joint
(standing to sitting - squat)
70
Gracilis (groin)
- parallel muscle
- superficial and on the medial surface of the thigh
- flexes knee
- adducts the thigh
- medially rotate the tibia on the femur
71
Hamstring
- parallel fibers
- includes bicep femoris, semimembranosus, and semitendinosus
- originates at ischial tuberosity
- run down the thigh to insert on both sides of the proximal tibia
- flexes the knee joint and extend hip
72
Calves (gastrocnemius)
- bipennate
- gastrocnemius is 2-headed
- fleshes out the superficial dorsum of the tibia
involved in:
- plantar flexor of the foot at the talocrural joint
- flexes the leg at the knee
- provides the force behind propulsion for walking, running, and jumping
73
What does the Circulatory System do?
- move materials entering the body (oxygen, water, nutrients)
- move materials within the body (wastes, hormones, immune cells)
- move materials leaving the body (wastes, carbon dioxide, heat)
74
How might movement be accomplished?
PRESSURE GRADIENT DRIVES FLOW
- need to move it faster
- carries nutrients and oxygen
- diffusion is WAY too slow
- compressing a fluid raises the pressure
75
Cardiac Anatomy
parts move in sync--> RHYTHMIC COORDINATION
- cardiac muscle
- pericardium
- septum
- atria
- ventricles
- vena cavae
- pulmonary arteries
- pulmonary veins
- atrioventricular valves
- coronary vasculature
76
Cardiac Muscle
- fibers are smaller than in skeletal muscle
- dependence on diffusion within the cells
- fibers are striated
- fibers are joined by intercalated disks (allow smooth force transferral and minimize cramping)
- fibers connected by gap junctions
- mitochondria account for 1/3 cell volume
- high vasculature
77
Pericardium
- membranous sac contain surrounding the heart
- serosa membrane that helps against abrasion
- connects to diaphragm for anchoring
78
Septum
- divides the heart into left and right sides
- contains conductive elements like a neuron
79
Atria
- compartments that lie at the top of the heart
- thin walled and small
- collect blood returning to the heart
- pump blood to ventricles
- do not generate a lot of force ("weaker")
Right Atrium = systemic circulation
Left Atrium = Pulmonary Circulation (lungs)
80
Ventricles
- compartments that lie at the bottom of the heart
- thick walled and large
- pump blood out to the blood vessels
- larger pressure gradient (further)
Right Ventricle pumps blood to lungs - slightly smaller/weaker
Left Ventricle pumps blood to tissues
81
Vena Cavae
- collect peripheral blood
- dump into right atrium
- inferior and superior vena cavae
82
Arteries carry blood _____ the heart
away from
83
Veins carry blood ______ the heart
toward
84
Pulmonary arteries carry blood _____ the lungs.
going to
85
Pulmonary Veins carry blood ______ the lungs.
leaving
86
Coronary Vasculature
- carries blood for the heart
- runs in grooves along cardiac surface
- very small
- possible rupture
87
Retrograde
back flow of blood in the body (NOT GOOD)
88
Atrioventricular (AV) Valves
- found between atria and ventricles
- opened by atrial contraction
- closed by ventricular contraction
- helps prevent back flow
89
Types of AV valves
- tricuspid valve (right side - 3 flaps)
- bicuspid (mitral) valve (left side - 2 flaps)
90
Mitral Valve Regurgitation
when blood in left ventricle pushes back up into left atrium
91
Semilunar Valves
- found at the ventricle/artery junction (aortic/pulmonary)
- prevent back flow
- look like half moon
92
Types of Circulatory Systems (2)
1. Open
2. Closed
93
Open Circulatory System
- lacks distinction between blood and interstitial fluid (hemolymph)
- bathes organs directly
- found in insects, other arthropods, and most mollusks
- concentration gradient is OK
- exchange rates are great
- all liquid goes through the heart
94
Closed Circulatory System
- confines blood to vessels
- rare
- HIGH concentration gradient
- OK exchange rates
- highest level of circulation of blood possible
95
Human Vasculature (blood vessels)
- conducts blood throughout the body
- varies in composition, structure
- handles, is constrained by pressure, pressure gradients
96
Types of Blood Vessels (6)
1. Arteries
2. Arterioles
3. Metarterioles
4. Capillaries
5. Veinules
6. Veins
97
Arteries
- carry blood away from the heart
- have lots of smooth muscle, elastic and fibrous tissue
- subjected to high blood pressure
98
Arterioles
- branch off arteries
- lack elastic and fibrous tissue
- have continuous smooth muscle layer
99
Metarterioles
- have only regions of smooth muscle (parts lack smooth muscles)
- allow blood to be shunted to/from capillaries
100
Capillaries
- are site for blood/interstitial exchange
- have only epithelial layer
101
Veinules
- have convergent flow pattern
- possess some smooth muscle
102
Veins
- are convergence point fro veinules
- have smooth muscle, some elastic tissue
- muscle contraction allows for blood in veins to move back up to heart
- small muscle contractions will compress veins pushing blood up to heart
103
All closed Circulatory Systems have... (3)
- a circulatory fluid (blood or hemolymph)
- a set of tubes (blood vessels)
- a muscular pump (heart)
104
Blood
- is a type of connective tissue
- red and white blood cells are in a plasma
- is primary circulatory matrix (in vertebrates)
55% plasma 45% RBC ~1% WBCs and platelets
105
Plasma
- consists of ~92% water and dissolved solutes including ions, proteins, hormones, antibodies
- Sodium and Chloride are major electrolytes
- transports gases and nutrients
- serves as the matrix for cellular components
106
Erythrocytes (RBCs)
- flattened biconcave discs (doughnut)
- inc SA for gas diffusion
- lack nuclei and mitochondria
- live about 120 days then removed from circulation by phagocytic cells in liver, spleen and bone marrow
- main goal is transport
- bags of hemoglobin
107
Hemoglobin
- iron containing proteins
- oxyhemoglobin = with O2
- deoxyhemoglobin = without O2
108
White Blood Cells (WBCs)
- are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders
- are produced and derived from multipotent cells in the bone marrow known a hematopoietic stem cells
- contain nuclei and mitochondria
- can squeeze through capillary walls then move through tissues in amoeboid fashion
109
WBCs - Granular
- have granules in cytoplasm (contain enzymes)
- release granules to fight against pathogens
- are phagocytotic
- enzymatically digest
110
Neutrophils
- basic, general immune cell
- kill, digest pathogens
- have multi-lobes nuclei
- are most abundant WBC
- inc neutrophils when stressed
111
BIG DINOSAUR SITUATION
Difficulties
- large mass, long necks, compression on vessels, work harder
Overcome
- multiple hearts, need higher pressure to get to target and come back or MASSIVE heart
112
Eosinophils
- pro inflammatory
- have distinctive red granules, 2-lobed nucleus
- more O2, more nutrients, heat
113
Basophils
- drive "immune surveillance"
- release histamine in their granules
- 1st line of defense
114
WBCs - Agranular
- lack enzyme rich granules
Two types:
Monocytes
Lymphocytes
115
Monocytes (WBC)
- largest WBC
- phagocytize large particles
116
Lymphocytes (WBC)
- smallest WBC
- produce antibodies
117
Platelets (Thrombocytes)
- not actually cells
- fragments of a much larger bone marrow cell
- megakarocyte
- promote clotting
- clotting cascade - rupture triggers the start
118
Platelets - rupture scenario
- stick to collagen exposed by damage to vessel
- stick to each other and physically plug the leak
119
Roles of Respiratory System
- modify air (warm and moisten)
- deliver olfactory cues
- produce sounds
- regulate blood pH
120
Types of Respiration (3)
1. External
2. Internal
3. Cellular Respiration
121
External Respiration
exchange of gases by diffusion between alveoli/lung capillaries
122
Internal Respiration
exchange of gases between capillaries/body cells
123
Cellular Respiration
use of O2 and production of CO2 inside cells (mitochondria)
124
Respiration is predicated on...
VENTILATION
125
Ventilation
breathing
- physical movement of air in and out of the lungs
inhale = inspire
exhale = expire
126
What has to happen to achieve inhalation and exhalation?
- pressure gradient created by a pump (exhale under pressure and inhale by negative pressure)
- need for bulk flow of air mass into and out of the body
127
Positive Pressure
pressure in lungs is increased (positive) compared to that of the outside air resulting in out flow
128
Negative Pressure
pressure in the lungs is lowered (negative) below that of external air pressure favoring in flow
129
What happens in high altitude?
high altitude = lower external pressure
- difficult to change internal pressure to be lower than external
- decreasing pressure that much makes it difficult to create pressure gradient and difficult to breathe
130
Issues with this respiration
- water flows in easily but the hydrogens removed from water is difficult to get rid of
- dependent on external pressure
- if we cannot change volume of thorax = dead
- dependent on muscles
131
Resistance...
opposes flow
- we want flow of gases
132
Flow...
= change in pressure
= 1/resistance
= change in pressure / resistance
133
Resistance...
= L (length of tube) / r^4 (radius of tube)
- inc radius = dec resistance
134
Ideal Surface for Respiratory Exchange
- thin
- lots of surface area
- elevated/stable temp
- highly vascularized
135
Problems with ideal surface...
- space
- energy
- eat/breathe in same path
- force can cause rupture
- thin/flexibility decreases with age
- high mitosis = cancer
136
2 Regions of Respiratory Anantomy
1. Upper Respiratory Tract - nose, paranasal sinuses, pharynx
2. Lower Respiratory Tract - larynx and down
137
Nasal Cavity
- divided in half by nasal septum - bone and cartilage
- 3 pairs of nasal conchae
- more SA
- moisten, warm and filter air
- lined with mucous membrane
- pseudostratified ciliated columnar epithelium
- extensive network of blood vessels
138
How does nasal cavity work?
- blood vessels warm incoming air
- mucus traps particles and pathogens
- cilia sweep it back toward throat to be swallowed
- pathogens destroyed by stomach
139
Pharynx
- funnel-shaped passage posterior to oral and nasal passages
- common to food, air
- occurs in 3 parts
140
Nasopharynx
- posterior to nasal cavity, above soft palate
- contains pharyngeal tonsil and opening of auditory tube
- balance pressure
141
Oropharynx
- posterior to oral cavity (region)
- below soft palate
- common passage for food and air
142
Laryngopharynx
- inferior to oropharynx
- connects to larynx and esophagus
143
What does the pharynx (nasopharynx, oropharynx, laryngopharynx) primarily do?
Warm and moisten air
144
Larynx
- composed of cartilage, ligaments, muscle
- uniquely respiratory tissue
- houses vocal cords
- mucous membrane extends inward and forms 2 pairs of vocal folds
145
False Vocal Cords...
close during swallowing to prevent food entry
146
True Vocal Cords...
vibrate to produce sounds
147
Glottis
opening between left and right true vocal cords
148
Epiglottis
- hinges over glottis during swallowing, preventing food inhalation
- works in consort with glottis which also closes
149
Why must babies learn to swallow before leaving the hospital?
swallowing is not reflexive
150
Why do men have an Adam's Apple?
- it occurs from high levels of testosterone
- usually makes the voice deeper
151
Thoracic Cage
- is composed of ribs, spine, and muscles
- affords protection, structure, and resistance
- chamber of variable volume with diaphragm to create pressure for air flow
152
Pleural Sacs (membranes)
- are fluid filled, double walled
- encompass lung
- afford structure, protection, ease, ventilation
- fluid makes it very hard to separate between outer surface of the lung and the inner surface of the ribs
153
Inspiration
- depends on alveolar pressure
- occurs when thoracic volume increases
- must increase the volume and decrease the pressure of the thoracic cage to inspire
154
Diaphragm
- contracts moving downward to inspire
- causes 60-70% of volume change
155
External Intercostals/Scalene Muscles
- lift ribs up and away form spine
- move ribs outward laterally
156
Trachea
- is a semi-flexible tube supported by cartilaginous rings
- enters thorax and divides into 2 branches
157
Primary Bronchi
- 1st divisions of trachea
- radius cannot be changed
- semi-rigid tubes supported by cartilage
- branch into smaller bronchi
158
Bronchioles
- smallest branches of the bronchi
- are small and collapsible
- have smooth muscle walls
- last branch before alveoli
159
Why use a paper bag for hyperventilating?
Breathing into the bag forces an increased inhalation of CO2 which makes your body slow the breathing because it doesn't want to inhale CO2 at such a high rate
160
Diameter _____ as branching _____.
decreases, increases
161
Surface Area ______ as branching ________.
increases, increases
162
Cross-Sectional Area _____ as branching _________.
increases, increases
163
Why is it better to stand up with hand over head after running too many sprints?
it allows your thoracic cage a better ability to expand to better the breathing
164
Why is it so hard to breathe in the Himalayas?
The external pressure is too low and we cannot get the internal pressure to be low enough to create a big enough pressure difference for bulk flow breathing to occur.
165
Adaptations to overcome Himalayan altitude?
- increase alveoli
- decrease resistance
- bigger lungs
- increase flow
- more tubes
166
Alveoli
- sacs at the end of terminal bronchioles
- are sights for gas exchange
- compose the majority of pulmonary tissue
- consist of a single epithelial layer
- lack muscular layer
- are in close association with capillaries
167
2 Subtypes of Alveoli
Type I
Type II
168
Type I Alveoli
- most common
- very thin
- high SA
- allow for gas exchange
169
Type II Alveoli
- less common
- secrete surfactant
170
Why is surfactant important?
helps break the surface tension of the moisture on the alveoli to allow for better expansion and easier breathing
171
Why are alveoli/lungs very vascularized?
- to increase circulation
- lungs have high conc. of O2 and blood will have low conc. causing an efficient diffusion flow and the blood will circulate faster
172
What is muscle tissue?
excitable tissue capable of contraction
