Chapter 7
The development of fibrosis in the elderly causes
Rapid fatigue and limited repair capabilities following injury.
The quadriceps are a group of anterior thigh muscles that include the __________ muscles
Rectus femoris, vastus medialis, vastus lateralis, and vastus intermedius
In an isometric contraction, the
Tension rises and the muscle shortens
In an isotonic contraction, the
Tension rises and the skeletal muscle's length changes
The muscle that inserts on the acrominon process and scapular spine is the
Trapezius
Of the following selections, the one that includes muscles that move the shoulder girdle is the
Trapezius, levator scapulae, pectoralis minor, and subclavius
The muscular floor of the pelvic cavity is formed by muscles that make up the
Urogenital and anal triangle
The muscle that originates along the entire length of the linea aspera of the femur is the
Vastus medialis
The typical result of repairing aging skeletal muscle tissue is
Formation of scar tissue
Athletes training to develop anaerobic endurance perform
Frequent, brief, intensive workouts
The origin of the frontalis muscle is the
Galea aponeurotica
There is no clear evidence that the benefits of regular exercise throughout life include
-Control of body weight -Increase in bone strength -Improving the quality of life
What are the three layers of connective tissue that are part of each muscle?
-Epimysium -Perimysium -Endomysium
What are the four groups of muscles that comprise the axial musculature?
-Head and neck -Vertebral column -Oblique and rectus muscles -Pelvic floor
The axial musculature consists of
-Muscles of the head and neck -Muscles of the spine and pelvic floor -Muscles of the trunk
What two major groups of muscles comprise the appendicular musculature?
-Pelvic girdle and upper limbs -Lower limbs
An example of an activity that requires anaerobic endurance is
A 5-yd dash
Mitochondrial activities are relatively efficient, but their rate of ATP generation is limited by the
Availability of oxygen
The primary energy reserve in muscle tissue is
Creatine phosphate (CP)
The names of the muscles of the tongue are readily identified because their descriptive names end in
Glossus
The muscle that inserts on the iliotibial tract and gluteal tuberosity of the femur is the
Gluteus maximus
A muscle producing peak tension during rapid cycles of contraction and relaxation is said to be ______________ tetany
Incomplete
The process of recruitment is the smooth but steady increase in muscle tension produced by
Increasing the number of active motor units
Two of the muscles comprising the rotator cuff are the
Infraspinatus and teres major
Resting tension in a skeletal muscle is called _______
Muscle tone
The thick filaments of a sarcomere consist of
Myosin
What is the primary functional difference between origin and an insertion?
Origin: attachment point doesn't move Insertion: attachment point does move
The amount of oxygen used in the recovery period to restore normal pre-exertion conditions is referred to as the
Oxygen debt
Bundles of muscle fibers called fascicles make up the connective tissue fibers of the
Perimysium
The layer of connective tissue that contains blood vessels and nerves is the
Perimysium
Fast fibers are the type of muscle fibers that
Produce powerful contractions but fatigue rapidly
Complete Tetanus
Produces maximum tension
Highly coordinated activities such as swimming, skiing, or typing are examples of the skeletal muscle function of
Producing movement
The muscles that arise on the humerus and the forearm and rotate the radius without producing flexion or extension of the elbow are the
Pronator teres and supinator
Tropomyosin
Protein cover of active sites
During anaerobic glycolysis,
Pyruvic acid is produced
The iliac crest is the origin of the
Quadratus lumborum
Voluntary control over swallowing, defecation, and urination are controlled by skeletal muscles that
guard entrances and exits
List the three muscles that are included in the hamstrings
-Biceps femoris -Semitendinosus -Gastrocnemius
What are the five functions performed by skeletal muscles?
-Produce movement of the skeleton -Maintain posture and body position -Support soft tissue -Guard entrances and exits -Maintains body temperature
List the four muscles that are included in the quadriceps
-Tensor fascia latae -Vastus intermedius -Vastus medialis -Vastus lateralis
Slow fibers are the type of muscle fibers that contain
-an extensive network of capillaries -the red pigment myoglobin -a relatively large number of mitochondria
A resting muscle generates most of its ATP by
Aerobic respiration
________ exercise requires oxygen and is of ________ duration than __________ exercise
1. Aerobic 2. Longer 3. Anaerobic
Acetylcholine
A neurotransmitter
When muscles are actively contracting, the process requires large amounts of energy in the form of
ATP
The neurotransmitter released from the synaptic vesicles that initiates an action potential in the sarcolemma is
Acetylcholine
Skeletal muscle fiber contraction begins when
Acetylcholine is released into the neuromuscular junction and binds to receptors on the sarcolemma.
The thin filaments of a sarcomere consist of
Actin
Summation
Addition of one twitch to another
Tendons are bundles of collagen fibers at the end of a skeletal muscle that
Attach muscle to bone
"Cross-Bridging"
Attach, pivot, detach, return
Aponeurosis
Broad sheet of collagen fibers
From the following selections choose the one that includes only muscles of facial expression
Buccinator, orbicularis oris, risorius, frontalis
Active sites on the actin become available for binding when
Calcium binds to troponin
The presence of intercalated discs is a characteristic unique to
Cardiac muscle cells
The system that accelerates oxygen delivery and carbon dioxide removal in muscles is the ___________ system
Cardiovascular
A muscle that inserts on the body of the mandible is probably involved in
Chewing
Hypertrophy
Enlargement
The dense layer of collagen fibers that surrounds an entire skeletal muscle is the
Epimysium
The three layers of connective tissues comprising each muscle are
Epimysium, perimysium, and endomysium
In the aging process, skeletal muscle fibers decrease in diameter, causing
Decreased muscular strength and endurance, and rapid fatigue
From the following selections, choose the one that includes the muscles that move the upper arm.
Deltoid, teres major, latissimis dorsi, pectoralis major
The system that releases hormones that adjust muscle metabolism and growth is the ___________ system
Endocrine
Cisternae
Expanded chambers of SR
Muscles that insert on the olecranon process of the ulna act to
Extend the forearm
When the gluteus maximus contracts it
Extends the thigh backward
In humans, slow fibers are not found in the muscles of the
Eyes and hands
Why do fast fibers fatigue more rapidly than slow fibers?
Fast fibers use anaerobic metabolism; better at generalizing short bursts of strength
What is the relationship among fatigue, anaerobic glycolysis, and oxygen debt?
Fatigue and the lack of oxygen cause anaerobic glycolysis.
When energy reserves in a muscle are exhausted or lactic acid levels increase,
Fatigue occurs
The superficial muscles of the spine are identified by subdivisions that include
Iliocostalis, longissimus, and spinalis
The system that defends skeletal muscles against infection and assist in tissue repairs after the injury is the ___________ system
Immune/Lymphatic
What are the differences between isometric contraction and isotonic contraction?
Isometric: muscle stays the same length even if the force of contraction increases. Isotonic: muscle is at a constant pulling w/ the same force, but shortens
The ability of skeletal muscles to produce continuous contractions results in the ability of the body to
Maintain posture and body position
During a specific action, the insertion is the
More movable end of a muscle
The system that controls skeletal muscle contractions is the __________ system
Nervous
Latent Period
No tension produced
The smallest functional unit of the muscle fiber is the
Sarcomere
In response to action potentials arriving from the transverse tubules, calcium ions are released from the
Sarcoplasmic reticulum
The hamstrings are a group of posterior thigh muscles that include the __________ muscles
Semitendinosus, biceps femoris, and semimembranosus
A twitch is the type of contraction represented by a
Single stimulus-contraction-relaxation sequence
The system that provides for muscle attachment in the body is the _________ system
Skeletal
Sarcomere Contraction
Sliding filament theory
The type of muscle cells that contract either automatically or in response to environmental or hormonal stimulation are
Smooth muscle cells
The type of muscle tissue that lacks myofibrils, sarcomeres, and striations is
Smooth muscle tissue
The function of layers of skeletal muscles that comprise the abdominal wall and floor of the pelvic cavity is to
Support soft tissue
The endomysium is the layer of connective tissue that
Surrounds each skeletal muscle fiber and ties adjacent muscle fibers together.
The command to contract is distributed throughout a muscle fiber by the
T tubules
The final step involved in skeletal muscle contraction is
The muscle cell relaxes and return passively to its resting length
Thin filaments at either end of the sarcomere are attached to interconnecting filaments that make up the
Z Lines
The length of time a muscle can continue to contract while supported by mitochondrial activities is referred to as
aerobic endurance