All Human Anatomy and Physiology Resources
Example Question #1 : Identifying Muscles Of The Trunk, Core, And Head
Which facial muscle is responsible for raising the corners of the mouth into a smile?
The zygomaticus major is a facial expression muscle that can raise the corners of the mouth during a smile. The muscle originates from the zygomatic arch and inserts in the fibrous tissue of the modiolus.
The frontalis is located within the forehead and helps raise the eyebrows. The orbicularis oris circles the mouth and helps to pucker the lips. The masseter is used to raise the mandible during mastication.
Example Question #2 : Identifying Muscles Of The Trunk, Core, And Head
Damage to what muscle would result in the inability to raise your arm above your head?
The upper fibers of the trapezius muscle elevate the scapula and raise the upper limb above the head. The trapezius muscle is innervated by the accessory nerve. Damage to the accessory nerve results in drooping of the shoulder and inability to raise the arm above the head. The deltoid muscle is also used to abduct the arm at the shoulder.
The rhomboid major serves to connect the scapula and the vertebrae, pulling the shoulders posteriorly. The levator scapulae elevates the medial angle of the scapula. The latissimus dorsi helps to adduct and extend the arm at the shoulder.
Example Question #3 : Identifying Muscles Of The Trunk, Core, And Head
Which of the following structures is associated with the chin?
The geniohyoid muscle is associated with the chin, as it is a muscle that is the passageway from the chin to the hyoid bone. Contraction of the geniohyoid can move the hyoid bone to further widen the airway, aiding in respiration.
The nuchal ligament is located at the back of the neck and helps maintain the vertical position of the head. The sternocleidomastoid muscles are located in the lateral portions of the neck and helps to turn the head from side to side. The iliocostalis muscles run down the back, connecting the posterior portions of the ribs; this muscle is deep to most other muscles in the back. The popliteus muscle is located poterior to the knee and helps to move the tibia posteriorly, relative to the femur.
Example Question #4 : Identifying Muscles Of The Trunk, Core, And Head
Which of the following structures is not involved in respiratory expiration?
Abdominal wall muscles
Serratus posterior inferior muscles
There are many structures that aid in the process of inspiration and expiration. Inspiration involves enlarging the thoracic cavity for the lungs to expand, while expiration compresses the cavity to allow carbon dioxide to leave. Inspiration will always be active, while expiration can be either passive or active. One of the most important structures for inspiration is the diaphragm. The diaphragm will contract and move downwards into the abdominal cavity, allowing the lungs to expand and draw in air. Muscles of forced expiration are the anterior abdominals, the internal intercostals, and the serratus posterior inferior muscles. They help to relax the diaphragm, which increases the abdominal pressure and pushes the ribs inwards.
Example Question #5 : Identifying Muscles Of The Trunk, Core, And Head
Which of the following muscles causes downward movement of the ribs?
The ribs are elevated and depressed by the muscles of the thoracic wall and neck. The external intercostals originate at the lower border of the ribs. With the help of the internal intercostals, they raise the ribs when inspiring. The scalene muscles of the neck work to lift the first two ribs mainly. The sternocleidomastoid muscles are attached to the sternum, and also lift upwards.
The transversus thoracis originates on the posterior part of the sternum and xiphoid, inserting into the costal cartilages of ribs 2 to 6. They pull the ribs down when expiring air.
Example Question #6 : Identifying Muscles Of The Trunk, Core, And Head
Which muscles aid in inspiration?
Intercostal muscles are responsible for expanding and contracting the thoracic cavity during forced breathing. During relaxed breathing, the diaphragm is responsible for changing the volume of the thoracic cavity, driving pulmonary ventilation. Internal intercostals depress the ribs during forced exhalation and the external intercostals elevate the ribs during forced inhalation. The subscapularis is one of the rotator cuff muscles, and its function is medial rotation of the humerus.
Example Question #7 : Identifying Muscles Of The Trunk, Core, And Head
Which of the following muscles is not part of the transversospinal group?
The transversospinal group is made up of the multifidi, the semispinalis group, and the rotatores group. The overall action of these muscles is extension and rotation of the vertebral column. The quadratus lumborum muscle laterally flexes the vertebral column, and, when bilaterally contracted, depresses the rib cage.
Example Question #8 : Identifying Muscles Of The Trunk, Core, And Head
Which hip motion does the iliofemoral ligament restrict?
The iliofemoral ligament connects the ilium to the femur and is taut in end range hip extension (as in doing front splits) and external rotation.
Example Question #9 : Identifying Muscles Of The Trunk, Core, And Head
Which muscle would likely be in use if a person wrinkled the skin above the eyes?
The occiptofrontalis muscle is responsible for pulling the skin of the forehead up and down. It is part of a sheet of muscle the extends from just above the eyes to the back of the head. The orbicularis oris is responsible for puckering the lips such as kissing. The masseter is in the jaw and assists in chewing. The temporalis muscle is also involved in chewing, but is situated on either side of the skull under the area commonly referred to as the temple. The zygomatic oculi does not exist.
Example Question #10 : Identifying Muscles Of The Trunk, Core, And Head
What large and flat muscle is responsible for allowing a person to lower their lips and jaw downward, but also stretches and tightens the skin of the neck?
The platysma is a broad, flat muscle that lowers the jaw and stretches the lips down or to the sides. When the entire sheet is contracted it can increase the diameter of the neck. This is the muscle men flex when trying to shave under the chin and along the superior and anterior portion of the neck.
The masseter is in the jaw and is involved in the chewing motion. The mentalis muscle furrows the chin, while the risorius and orbicularis oris muscles pull the corners of the mouth out and in respectively.