Exploring Skeletal Muscle Organization and Filament Structure

This video tutorial explores the structure of muscles, starting from the organ level and breaking it down to the molecular level. It covers the components of muscle cells, including organelles like the sarcolemma and transverse tubules, and explains the role of myofibrils and myofilaments in muscle contraction. The tutorial also introduces the concept of sarcomeres and how actin and myosin filaments interact to facilitate muscle movement.

What is the primary function of myofilaments in muscles?

• To protect muscles

• To store energy

• To transport nutrients

• To contract muscles

What connects bones to muscles?

• Tendons

• Cartilage

• Ligaments

• Fascicles

What is a fascicle?

• A type of tendon

• A muscle organ

• A type of bone

• A bundle of muscle fibers

What is the special name for the cell membrane of a muscle cell?

• Endoplasmic reticulum

• Myofibril

• Transverse tubule

• Sarcolemma

What is the role of transverse tubules in muscle cells?

• To transport oxygen

• To produce energy

• To conduct action potentials

• To store calcium

What does the sarcoplasmic reticulum store?

• Nutrients

• Calcium

• Oxygen

• Proteins

What are myofibrils made up of?

• Myofilaments

• Muscle fibers

• Tendons

• Fascicles

Which proteins are involved in muscle contraction?

• Hemoglobin and Myoglobin

• Keratin and Fibrin

• Collagen and Elastin

• Actin and Myosin

What happens to the sarcomere length when a muscle contracts?

• It fluctuates

• It increases

• It decreases

• It remains the same

What is the term for the distance between two Z lines in a muscle?

• Sarcolemma

• Myofibril

• Fascicle

• Sarcomere