Muscle Anatomical Structures

These flashcards cover key concepts, definitions, and mechanisms related to muscle anatomical structures and physiology.

What are the three types of muscle tissue?

Skeletal muscle tissue, Cardiac muscle tissue, Smooth muscle tissue.

What is the main function of skeletal muscle tissue?

To attach to the skeletal system and allow movement.

List the six functions of skeletal muscle tissue.

1. Produce skeletal movement 2. Maintain posture and body position 3. Support soft tissues 4. Guard entrances and exits 5. Maintain body temperature 6. Store nutrient reserves.

What are the three layers of connective tissues in muscles?

Epimysium, Perimysium, Endomysium.

Define the Epimysium.

The exterior collagen layer connected to deep fascia, separates the muscle from surrounding tissues.

What are sarcomeres and where are they found?

Sarcomeres are structural units of striated muscle fibers found within myofibrils.

What is the role of the sarcoplasmic reticulum (SR) in muscle cells?

SR surrounds each myofibril and helps transmit action potentials to myofibrils.

What initiates muscle contraction in skeletal muscle fibers?

Calcium ions (Ca2+) bind to troponin, exposing the active site of F-actin.

What is the sliding filament theory?

The idea that thin filaments slide toward the M line alongside thick filaments during muscle contraction.

Differentiate between isotonic and isometric contraction.

Isotonic contraction changes muscle length producing motion, while isometric contraction develops tension without changing length.

What is muscle fatigue?

A condition where muscles can no longer perform a required activity and is caused by metabolic depletion and damage.

Identify the three major types of muscle fibers.

Fast fibers, Slow fibers, Intermediate fibers.

What happens during muscle hypertrophy?

Muscle growth from heavy training, increasing diameter of muscle fibers and number of myofibrils.

What are intercalated discs and their function in cardiac muscle?

Specialized contact points between cardiocytes that maintain structure and enhance electrical connections.

How do smooth muscle cells differ from skeletal muscle cells?

Smooth muscle cells are non-striated, spindle-shaped, and have a single nucleus.

What is the concept of automaticity in cardiac muscle tissue?

The ability of cardiac muscle to contract without neural stimulation, controlled by pacemaker cells.