Muscle Physiology

During a tug-of-war game, Evelyn pulls the rope with all her strength, while another muscle works against her contracting working muscle. What is this opposing muscle called?

• Antagonist

• Posture

• Gliding

• Agonist

During a biology class, Mason is examining a diagram of muscle fibers. He notices a region labeled 'Light I Band.' What does this region consist of? 

• Myosin filaments only

• Actin filaments only

• Myosin and actin filaments

• none of the above

During a biology lab, Kai is examining muscle cells under a microscope. He wonders which structure functions in storing Ca². 

• Sarcoplasmic Reticulum

• T Tubules

• Mitochondria

• Fascicle

What two chemicals are necessary for muscle contraction to occur?

• Niacin and Potassium
• Calcium and ATP
• Sodium and Potassium
• Ach and Potassium

During a biology class, Michael is examining a muscle sample under a microscope. He notices that the myofibrils have repeating contractile units along their length. What is the name given to these contractile units?  

• Fascicles

• Perimysium

• Sarcomere

• Fascia 

A motor unit is made up of _______________.

• all the muscle fibers within a given muscle
• a motor neuron and the muscle fibers it innervates
• all the neurons going into an individual section of the body
• a fascicle and a nerve

The crossbridges involved in muscle contraction are located on the ________________.

• myosin filaments
• actin filaments
• tropomyosin 
• troponin

The neurotransmitter always used at the neuromuscular junction is: 

• It depends upon the type of muscle being innervated
• noradrenaline
• acetylcholine
• dopamine

Avery is studying muscle structure in biology class. The teacher asks, "Avery, can you tell me from where to where a sarcomere runs in a myofibril?"

• one Z line to the next Z line

• one H zone to the next H zone

• one A band to the next A band

• one end of a skeletal muscle to the opposite end

During a biology class, Isla is examining a diagram of muscle fibers. She is asked to identify the name of the thick myofilaments present in the muscle. What should Isla answer?

• Actin

• Myosin

• Myoglobin

• Titan