Muscle Fibers

Which one of the following is a key characteristic of Fast Twitch muscle fibers?

• They are red in color, meaning they contain a lot of mitochondria

• They contract rapidly with great force but fatigue fast

• They are recruited for long duration activities

• They contain high numbers of Mitochondria

Which one of the following is a key characteristic of slow twitch muscle fibers?

• They contain large amounts of Mitochondria

• They are fast to fatigue

• They can be both white and red in appearance

• They contain low numbers of Mitochondria

What two chemicals are necessary for muscle contraction to occur?

• Niacin and Potassium

• Calcium and ATP

• Actin and Myosin

• Phosphorus and Potassium

When there is no nerve impulse, what is the name of the protein that covers the binding sites on actin?

• Myosin

• Troponin

• Titan

• Tropomyosin

A bundle of muscle fibers is called __________.

• Sarcomere

• Fascicle

• Tendon

• Muscle body

Tags

NGSS.HS-LS1-4

List the structures of a muscle from largest to smallest.

• myofibril, muscle fiber, fascicle

• fascicle, muscle fiber, myofibril

• fascicle, sarcomere, muscle fiber

• myofibril, fascicle, sarcomere

When the troponin molecule's binding site is empty the muscle is?

• full contraction

• complete tetanus

• at rest

• summation

Which of the following describes the sarcomere? 

• The basic unit of muscle’s cross-striated myofibril

• A protein band which defines the boundary between one sarcomere 

• Various muscle proteins 

• Contains the protein, actin

Arrange the structures of a muscle from largest to smallest.

• Myofibril, muscle fiber, fascicle

• Fascicle, muscle fiber, myofibril

• Fascicle, sarcomere, muscle fiber

• Myofibril, fascicle, sarcomere

Tags

NGSS.HS-LS1-2

What holds oxygen in muscles cells?

• Myofibrils

• Myoglobin

• Fascicles

• Periosteum