Ch. 10-11 anatomy
D) Myosin Head Pivoting Stored energy in the 1.__________ molecule is used to pivot the 2________ head toward the 3.__________. This action is called the 4.__________ _________ releasing ADP.
1. ATP 2. Myosin 3. m-line 4. Power stroke
Name the 3 layers of connectice tissue found in a muscle and describe the location of each.
1. Endomysium- surrounds muscle fiber 2. Perimysium- bundles of muscle fibers are surrounded 3. Epimysium- entire muscle is surrounded
What are the 3 layers of connective tissue comprising each muscle?
1. Epimysium 2. Perimysium 3. endomysium
What do skeletal muscles contains?
1. Muscle tissue 2. Connective tissue 3. blood vessels 4. Nerves
Name the muscle layers in order from the exterior to the interior and describe what is found in each layer.
1. Muscle- contains bundles of fascicle 2. Fascicle- bundles of fibers 3. Fiber- muscles of myofibril (muscle cell) 4. Myofibril- bundles of filaments 5. Filaments- thick or thin filaments
C) Cross-Bridge Formation Once active sites are exposed, the 1.________ heads bind to them forming 2.___________ 3_________
1. Myosin 2. Cross 3. Bridge
Name the 2 types of filaments and describe what type of molecules is found on each.
1. Thick- composed of myosin molecules each with tail and head 2. Thin- twisted strand of actin molecules
B) Active Site Exposure Calcium binds to 1.__________ which leads to the exposure of the active site on 2.________ 3.___________ of the 4._________ filaments .
1. Troponin 2. Actin 3. Molecule 4. Thin
What are the 5 primary functions of muscular system?
1.Produce movement of Skeleton 2.Maintain posture and body position 3.support of soft tissue 4.guard entrances and exits 5.maintain body temperature
What is sarcomere?
A repeating unit of thick and thin filaments
E) Cross-Bridge Detachment The link between the myosin head and the active site breaks due to the binding of _________. The active site is now exposed and able to form another ___________ __________
ATP; Cross-bridge
The neurotransmitter released from the synaptic vesicles that initiates an action potential in the sarcolemma is?
Acetylcholine
The thin filaments of a sarcomere consist of?
Actin
Tendons are bundles of collagen fibers at the end of skeletal muscle that?
Attach muscle to bone
What is a sarcomere?
Basic functional unit of muscle
A) Contraction Cycle Once ACh released from the axon terminal and binds to the receptors in the motor end plate an icon is released that exposes the active site on the thin filaments. What is the ion? ______________
Calcium
What is muscle fatigue?
Energy reserves in the muscle
The dense layer of collagen fibers that surrounds an entire skeletal muscle is the?
Epimysium
What are slow fibers?
Fibers reach peak tension 3x longer
What are fast fibers?
Fibers reach peak tension very quickly after stimulation
What oxygen debt?
Lose of oxygen due to the body's demand during exercise
The portion of the sarcolemma that contain receptors that bind ACh is called the _________ __________ _________.
Motor end plate
Describe the basic structure of a sarcomere?
Myofibrils of thick and thin filaments
The thick filaments of a sarcomere consists of?
Myosin
Skeletal muscles contract only under the ___________ __________ control.
Nervous system
The connection between the nervous system and the muscular system is called a ______________ _____________.
Neuromuscular junction
Where are the blood vessels and nerves found in the muscle?
Penetrate through epimysium and permysium
Bundles of muscle fibers called fascicles are surrounded by connective tissue fibers of the?
Perimysium
The layer of connective tissue that contains blood vessels and nerves is the?
Perimysium
F) Myosin Reactivation When a free myosin head splits ATP in ADP and P, ___________ is released and the myosin ________.
Phosphorus; Recox
The release of ACh from the axon terminal results in changes in the _________ that trigger the _____________ of the muscle fiber.
Sarcolemma; contraction
Where would you expect to find the greatest amount of calcium in a resting skeletal muscle fiber?
Sarcoplasmic reticium
In response to action potentials arriving from the transverse tubules, calcium ions are released from the?
Sarcoplasmic reticulum
The endomysium is the layer of connective tissue that?
Surrounds each skeletal muscle fiber and ties adjacent the muscle fibers together
What is the space called that is located between the axon terminal and the sarcolemma?
Synaptic cleft
What is the sliding filament theory?
The binding of myosin molecules that actin molecules forming cross-bridges that causes the sarcomere to shorten
Skeleton muscles are considered ____________ because we have control over their contractions.
Voluntary