Anatomy Chap 7
Muscles that insert on the olecranon process of the ulna probably act to?
Extend the forearm
When energy reserves in a muscle are exhausted or lactic acid levels increase?
Fatigue occurs
The origin of the frontails muscle is the?
Galea Aponeurotica
Interactions between actin and myosin filaments of the sarcomere are responsible for
Muscle contraction
The advantage of having many nuclei in a skeletal muscle fiber?
The ability to produce large amounts of enzymes and structural proteins needed for contraction.
What is the function of the transverse tubule?
To transmit muscle impulses to the cell's interior
The complex known as the triad consists of
Transverse tubule and terminal cisternae
The command to contract is distributed throughout a muscle fiber by the
Transverse tubules
At rest, active sites on the actin are blocked by
Tropomyosin molecules
When a calcium ion blinds to troponin?
Tropomyosin moves out of the groove between the actin molecules
At rest, the tropomyosin molecule is held in place by
Troponin molecules
The all-or-none response means that
When a muscle fiber contracts, it contracts completely
The area of the sarcomere containing the thick filaments is the
A band
A muscle cramp is most likely due to lack of
ATP
Creatine phosphate?
Acts as an energy reserve in muscle tissue
A resting muscle generates most of its ATP by?
Aerobic respiration
Which of the following is (are) a function of skeletal muscle?
All of the above
Each of the following terms is a descriptive word for a muscle's action EXCEPT one. Indentify the exception.
Buccinator
The area of the sarcomere that contains only thin filaments is the
C band
The sarcoplasmic reticulum stores
Calcium ions
In response to action potentials arriving from the transverse tubules, the sarcoplasmic reticulum releases
Calcium ions.
Which of the following is NOT characteristic of cardiac muscle?
Cardiac muscles are not striated
Muscles ending in the suffix -costal would be found in the?
Chest
Fast fibers?
Contract quickly
Compared to skeletal muscle, smooth muscle?
Contracts and relaxes more slowly
The delicate connective tissue that surrounds the skeletal muscle fibers and ties adjacent muscle fibers together is the?
Endomysium
Myofibrils are made of primarily of?
Epimyosin
During activities requiring aerobic endurance, ?
Glycogen and glycolysis are the primarily sources of reserve energy
Skeletal muscle fibers differ from "typical cells" in that these muscle fibers?
Have many nuclei
The more movable end of a muscle is the?
Insertion
Calcium ions are released from the sarcoplasmic reticulum during the __ phase of contraction.
Latent
A muscle that inserts on the greater tubercle of the humerus is most likely involved in?
Lateral rotation
Which of the following is NOT a muscle of mastication?
Mentails
At the neuromuscular junction, the muscle fiber membrane is folded to form a?
Motor end plate
Neurotransmitters that cause skeletal muscle contraction are normally stored in
Motor neuron endings
An example of partial but sustained contraction would be
Muscle tone
Multi-unit smooth muscle?
None of the above
The "kissing muscle" that purses the lips is the?
Orbicularis oris
The amount of oxygen needed to support the conversion of lactic acid to glycogen is called the
Oxygen debt
Which of the following inserts into fascia, rather than a bone?
Palmaris longus
Nerves and blood vessels that service the muscle fibers are located in the connective tissues of the?
Perimysium
The smooth but steady increase in muscle tension produced by increasing the number of active motor units is called?
Recruitment
Which of the following is NOT true when comparing red and white muscle fibers?
Red muscles have fewer mitochondria than white muscles
Activities that require anaerobic endurance?
Require maximal contraction of muscles for short periods of time
The functional unit of skeletal muscle is the
Sacromere
The striated appearance of skeletal muscle results from?
Sacromere arrangement
The cytoplasm of a skeletal muscle fiber is called the
Sacroplasm
Which of the following statements is INCORRECT?
Skeletal muscles are responsible for pumping action of the heart.
Non-striated, involuntary muscle is?
Smooth
Creatine phosphate serves to
Supply energy to synthesize ATP
The space between the neuron and the muscle is the?
Synaptic cleft
The ___ contains vesicles filled with acetylcholine
Synaptic knob
The enzyme acetlycholinesterase causes acetylcholine to
decompose