Chapter 10 Flashcards
Three types of muscle tissue.
Skeletal.
Cardiac.
Smooth.
5 functions of skeletal muscles.
Produce skeletal movement. Maintain body position. Support soft tissues. Guard body openings. Maintain body temperature.
Three layers of connective tissue on muscles.
Epimysium.
Perimysium.
Endomysium.
Most superficial of the three layers of connective tissue on muscles.
Epimysium.
Three characteristics of Epimysium.
Exterior collagen layer.
Connected to deep fascia.
Separates muscle from surrounding tissues.
What surrounds a muscle fascicle (fiber bundles)?
Perimysium.
What connective tissue is deep to the epimysium and superficial to the endomysium?
Perimysium.
Bundles individual muscle cells/fibers.
Endomysium.
What’s a muscle fascicle?
A bundle of muscle cells/fibers.
Contains blood vessel and nerve supply to fascicles.
Perimysium.
What does Endomysium surround?
Individual muscle cells/fibers.
Endomysium contains _______ and _________ contacting muscle cells/fibers.
Capillaries.
Nerve Fibers.
Which connective tissue contains satellite cells (stem cells) that repair damage?
Endomysium.
Where do epi, peri, and endo mysium come together?
Give example.
At ends of muscles to form connective tissue attachment to bone matrix.
i.e., tendon or aponeurosis.
What are skeletal muscles controlled by?
Nerves of the central nervous system.
The only kind of voluntary muscle?
Skeletal.
Muscle vascular system do what three things?
Supply large amounts of oxygen.
Supply nutrients.
Carry away wastes.
A muscle is made up of multiple ____________.
Muscle fascicles.
One muscle fascicle made of how many muscle fiber/cells?
8.
Each muscle fiber/cell is made of multiple _________.
Myofibrils.
Myofibrils consist of _________.
Sarcomeres.
Connective tissue come together to form _________
Tendons.
Contractile unit of muscle cell?
Sarcomere.
The cell membrane of a muscle cell.
The Sarcolemma.
Surrounds the sarcoplasm (cytoplasm of muscle fiber/cell)
Sarcolemma.
What begins contractions in the sarcolemma?
Change in the transmembrane potential.
Allows smooth contraction of muscles.
Transverse tubules.
Nerve meets ________ to trigger muscle cell sarcoplasm.
Sarcolemma.
Made up of bundles of protein filaments (myofilaments)
Myofibrils.
What are responsible for muscle contractions?
Myofilaments.
Two types of myofilaments, and what they’re made of.
Thin, Protein actin.
Thick, protein myosin.
A membrous structure surround each myofibril?
Sarcoplasmic Reticulum.
Function of Sarcoplasmic Reticulum?
Helps transmit action potential to myofibril.
The contractile units of muscle?
Sarcomeres
What make up myofirbrils?
Sarcomeres.
_________ form visible patterns within myofibrils.
Sarcomeres.
A striped or striated pattern within myofibrils?
Muscle Striations.
Two types of Muscle striations.
Thick filaments (A bands) .
Thin filaments (I bands).
Skeletal muscle, what surrounds and what does it contain?
Epimysium.
Muscle Fascicles.
Muscle Fascicle, what’s it surrounded by and what does it contain?
Perimysium.
Muscle fibers.
Muscle Fiber, What’s it surrounded by and what does it contain?
Endomysium.
Myofibrils.
Myofibril, what’s it surrounded by and what does it contain?
Sarcoplasmic reticulum.
Sarcomeres (Z line to Z line)
Action Potential (electric signal) travels along nerve axon and ends where?
Synaptic terminal.
Muscle _______ is active and requires energy.
Contraction.
Muscle _______ is passive and doesn’t require energy.
Relaxation.
Two ways we can contract our muscles?
Isotonic.
Isometric.
Skeletal muscle fibers shorten as ____ filaments slide between _____ filaments.
Thin.
Thick.
What triggers muscle contraction ?
Free Ca2+ in the sarcoplasm.
Sarcoplasm releases Ca2+ when what happens?
When a motor neuron stimulates the muscle fiber.
Concentric contraction (muscle shortens) happen if.... Is this isotonic or isometric?
muscle tension > resistance.
Isotonic.
Eccentric contraction (muscle lengthens) happens if.... Is this isotonic or isometric?
muscle tension< resistance.
Isotonic.
What happens in an isotonic contraction?
Skeletal muscle develops tension and changes length, resulting in motion.
What happens in an isometric contraction?
Skeletal muscle develops tension but doesn’t change length.
3 ways a muscle returns to resting length.
elastic forces.
opposing muscle contractions.
gravity.
What’s an elastic force, and what does it do?
The pull of elastic elements (tendons and ligaments).
Expands the sarcomeres to resting length.
What does it mean to oppose muscle contraction? What does it?
Reverse the direction of the original motion.
Pairs of muscles opposing each other.
Muscle contraction requires _____.
ATP.
Muscles store enough _____ to start contraction.
energy.
As muscles continue to contract, muscle fibers must manufacture more ______ as needed.
ATP.
What’s ATP?
Adenosine triphosphate, the active energy molecule.
What’s CP?
Creatine phosphate, the storage molecule for excess ATP energy in resting muscle.
2 ways a cell produces ATP.
Aerobic metabolism.
Anaerobic glycolysis,
What happens in aerobic metabolism?
Fatty acids > Glucose (1 molecule) > 34 ATP molecules.
What happens in anaerobic glycolysis?
Fatty acids > Glucose (1 molecule) > 2 ATP molecules.
The primary energy source of resting muscles?
Aerobic Metabolism.
The primary energy source for peak muscular activity?
Anaerobic Glycolysis.
At peak exertion, pyruvic acid builds up, is converted to ________.
lactic acid.
When muscles can no longer perform a required activity, they are _______.
fatigued.
4 results of muscle fatigue?
Depletion of metabolic reserves.
Damage to sarcolemma and sarcoplasmic reticulum.
Low pH (lactic acid).
Muscle exhaustion and pain.
The time required after exertion for muscles to return to normal.
The recovery period.
2 things that happen during recovery period?
Oxygen becomes available.
Mitochondrial activity resumes.
The removal and recycling of lactic acid by the liver?
The Cori Cycle.
Liver converts lactic acid to _______.
Pyruvic acid.
During the Cori cycle, ______ is released to recharge muscle glycogen reserves.
Glucose.
What happens during oxygen debt after exercise.
The body needs more oxygen than usual to normalize metabolic activities, resulting in heavy breathing.
Active muscles produce ____.
heat.
Up to 70% of __________ can be lost as heat, raising body temperature.
muscle energy.
Define muscle power.
The maximum amount of tension produced.
Define muscle endurance.
The amount of time an activity can be sustained.
What do muscle power and endurance depend on?
The types of muscle fibers.
Physical conditioning.
3 types of skeletal muscle fibers?
Fast fibers.
Slow fibers.
Intermediate fibers.
3 characteristics of fast fiber muscles…
Contract very quickly.
Have strong contractions.
Fatigue quickly.
Which muscle fibers have large diameter, large glycogen reserves, few mitochondria.
Fast fibers.
3 characteristics of slow fiber muscles.
Slow to contract.
Slow to fatigue.
High oxygen supply.
Which muscle fiber have small diameter, more mitochondria and contain myoglobin?
Slow fibers.
Muscle fibers that are mid sized, have low myoglobin, more capillaries.
Intermediate fibers.
White muscle is made mostly of which fibers?
Fast fibers (e.g. chicken breast)
Red muscle is made mostly of which fibers?
Slow fibers (e.g. chicken legs)
What muscle hypertrophy?
Muscle growth from heavy training.
3 effects of muscle hypertrophy.
Increases diameter of muscle fibers.
Increases number of myofibrils.
Increases mitochondria, glycogen reserves.
3 things muscle atrophy reduces.
muscle size.
tone.
power.
What fibers does anaerobic endurance use?
Fast fibers.
How is anaerobic endurance improved?
Frequent, brief, intensive workouts.
Hypertrophy.
Aerobic endurance is improved by?
repetitive training.
cardio training.
What happens with prolonged in activity to muscles?
Fibrous tissue may replace muscle fibers.
