Muscle Groups
Movement
Muscle Fibers
~Anything Goes~
100
This highlighted muscle group in the image below.
What is the trapezius?
100
During muscle contraction, these two proteins interact to shorten the muscle fiber.
What are actin and myosin?
100
This small molecule stores chemical energy produced by the mitochondria.
What is ATP?
100
This circular facial muscle is responsible for closing the eyelids.
What is the orbicularis oculi?
200
This muscle group covers the front of the femur and is responsible for knee extension.
What are the quadriceps?
200
This happens to a muscle during a concentric contraction.
What is the muscle shortens?
200
This diagram shows the structural unit of a muscle fiber.
What is a sarcomere?
200
This plasma membrane surrounds muscle fibers just beneath the endomysium.
What is the sarcolemma?
300
This muscle group turns and flexes the head and neck.
What are the sternocleidomastoid muscles?
300
This is the term for the muscle primarily responsible for initiating a movement.
What is the agonist?
300
Slow-twitch muscle fibers are resistant to this.
What is fatigue?
300
The rush of this ion into the muscle cell helps generate the action potential that starts muscle contraction.
What is sodium?
400
The highlighted muscle group in the image below.
What is the brachioradialis?
400
This facial muscle, known as the "smiling muscle," elevates the corners of the mouth.
What is the zygomaticus major?
400
This oxygen-binding protein is found in striated muscles.
What is myoglobin?
400
These types of muscles are found in the walls of the uterus.
What are smooth muscles?
500
These muscles, running along each side of the spine, maintain posture and assist in spinal extension.
What are the erector spinae muscles?
500
This is the space where neurons connect with muscle fibers to initiate movement.
What is the neuromuscular junction?
500
The conversion between fast-twitch muscle subtypes can occur in response to this kind of activity.
What is resistance or endurance training?
500
This is the only muscle in the human body attached at only one end.
What is the tongue?