10. Muscles

True or False: if false, choose the answer that best corrects the statement.

During a muscle contraction, the origin moves towards the insertion.

The flexor carpi ulnaris is a muscle that adducts and flexes the hand at the wrist. The muscle attaches to both the humerus and the base of the 5th metacarpal. Based on the movement that this muscle performs, which attachment is the origin?

The diagram below shows some of the muscles used for chewing. Using your knowledge of the bones, identify the insertion of the masseter.

Which eye muscle passes through the trochlea and turns the eye inferiorly and laterally?

a. Lateral rectus muscle

b. Inferior rectus muscle

c. Inferior oblique muscle

d. Superior oblique muscle

Mark the following statements as true or false. If the statement is false, correct it to make a true statement.

b. The latissimus dorsi muscle is a major abductor of the arm

​​Which of the following muscles flexes the thigh, but also laterally flexes the vertebral column when its origin and insertion switch?

a. Sartorius muscle

b. Psoas major muscle

c. Iliacus muscle

d. Rectus abdominis muscle

Match the muscle with its main action: ​    

____Vastus medius muscle     

____Gracilis muscle     

____Gluteus medius muscle     

____Gastrocnemius muscle     

____Biceps femoris muscle     

____Tibialis anterior muscle​

a. Adducts thigh

b. Extends thigh and flexes leg

c. Plantarflexes foot

d. Abducts thigh

e. Dorsiflexes foot

f. Extends leg

Explain how the diaphragm muscle is able to increase the size of the thoracic cavity even though it doesn't insert into a bone.

Why do you think that the muscles of the erector spinae and transversospinal muscle groups remain in a state of continual contraction when we are upright?

The rectus femoris muscle originates from the anterior superior iliac spine and inserts into the tibial tuberosity. Predict its main actions with only this information.

Elise is a competitive gymnast who strained muscles in her left lower limb doing a tumbling pass. She has pain with extension of her leg and inversion of her foot. Which muscles did she potentially strain?

Chris is training for his black belt in karate and is working on developing a stronger punch. Which muscles do you recommend that he strengthen to improve his punch? Explain.

Ms. Hendrix suffered a severe hip fracture that required hip replacement surgery. After an extended recovery period, she is undergoing physical therapy to regain strength and mobility.

b. Which muscles were likely affected by the hip replacement surgery, and to which parts of the bone do they attach?

Ms. Hendrix suffered a severe hip fracture that required hip replacement surgery. After an extended recovery period, she is undergoing physical therapy to regain strength and mobility.

c. Which actions could Ms. Hendrix perform to strengthen these muscles?