Muscular System lab Review flash cards

30 question-and-answer flashcards covering muscle fiber anatomy, histology of different muscle types, major muscle groups, and key knee joint structures.

What connective tissue sheath surrounds a single skeletal muscle fiber?

Endomysium

What is the plasma membrane of a muscle fiber called?

Sarcolemma- Outer mbn of muscle fiber as protective barrier

Name the three parts of a neuromuscular junction.

Synaptic knob of motor neuron, synaptic cleft, and motor end plate

What is the cytoplasm of a muscle fiber termed?

Sarcoplasm

Which cylindrical organelles fill most of a muscle fiber and contain sarcomeres?

Myofibrils

What is the functional contractile unit of skeletal muscle?

Sarcomere

Which myofilaments form the A band of a sarcomere?

Primarily thick myofilaments (with overlapping thin filaments)

Within a sarcomere, which zone contains only thick filaments and no thin filaments?

H band/H zone

What structures mark the boundaries of a sarcomere?

Z lines

Which invaginations of the sarcolemma conduct action potentials into the muscle fiber’s interior?

T-tubules (transverse tubules)

Which membrane system stores and releases calcium ions in muscle fibers?

Sarcoplasmic reticulum

What connective tissue layer encloses an entire skeletal muscle?

Epimysium

Which connective tissue surrounds individual fascicles?

Perimysium - surrounds round bundles of muscle fibers in skeletal muscles

How would you describe the shape of skeletal muscle fibers in cross-section?

Cylindrical

What microscopic feature gives skeletal and cardiac muscle their banded appearance?

Striations

In cross section, what do the dark dots inside a skeletal muscle fiber represent?

Myofibrils

Which muscle tissue is composed of spindle-shaped cells with a single central nucleus and no striations?

Smooth muscle

Which organ is commonly used in lab to view the two layers of smooth muscle?

Small intestine

Name the specialized junctions that connect cardiac muscle cells end-to-end.

Intercalated discs

List the four muscles of the rotator cuff.

Supraspinatus, infraspinatus, subscapularis, and teres minor

List the four muscles that form the quadriceps femoris group.

Rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius

Name the three muscles that compose the hamstring group.

Biceps femoris, semimembranosus, and semitendinosus

Which cartilage structure cushions the lateral side of the knee joint?

Lateral meniscus

Which ligament of the knee prevents posterior displacement of the tibia?

Posterior cruciate ligament (PCL)

Which ligament of the knee prevents anterior displacement of the tibia?

Anterior cruciate ligament (ACL)

What is another name for the fibular collateral ligament of the knee?

Lateral collateral ligament (LCL)

What is another name for the tibial collateral ligament of the knee?

Medial collateral ligament (MCL)

Which ligament connects the anterior horns of the medial and lateral menisci?

Transverse ligament of the knee

In anatomical terminology, what region does the term “arm” specifically refer to?

The proximal part of the upper limb between shoulder and elbow

In anatomical terminology, what region does the term “leg” specifically refer to?

The distal part of the lower limb between knee and ankle