Muscles Flashcards
What is the origin of the Masseter muscle?
Zygomatic Arch
The Masseter is a key muscle involved in mastication.
List the insertions of the Masseter muscle.
- Mandibular angle
- Mandibular ramus
These insertions allow the Masseter to effectively elevate the mandible.
What action does the Masseter muscle perform?
Elevates mandible
The Masseter is primarily responsible for closing the jaw.
What is the origin of the Temporalis muscle?
Temporal fossa of the temporal bone
The Temporalis muscle is another important muscle of mastication.
What are the actions of the Temporalis muscle?
- Elevates mandible
- Retracts mandible
These actions contribute to the complex movements of chewing.
What is the origin of the Sternocleidomastoid muscle?
- Manubrium of sternum
- Medial clavicle
The Sternocleidomastoid is crucial for head movement.
What is the insertion of the Sternocleidomastoid muscle?
Mastoid process of the temporal bone
This insertion allows for significant rotational movement of the head.
What actions does the Sternocleidomastoid muscle perform?
- Flexes head
- Rotates head laterally
The muscle plays an essential role in neck mobility.
What is the origin of the Scalenes muscles?
Transverse processes of the cervical vertebrae
The Scalenes consist of anterior, middle, and posterior muscles.
What is the insertion of the Scalenes muscles?
Anterior surface of ribs 1-2
The Scalenes assist in elevating the first two ribs.
List the actions of the Scalenes muscles.
- Flexes neck
- Rotates neck
- Elevates ribs 1-2
The Scalenes are important for respiration and neck stability.
What is the origin of the Pectoralis minor muscle?
Ribs 3-5
The Pectoralis minor is involved in movements of the scapula.
What is the insertion of the Pectoralis minor muscle?
Coracoid process of the scapula
This insertion is critical for the muscle’s action on the scapula.
What actions does the Pectoralis minor muscle perform?
- Depresses scapula
- Downwardly rotates scapula
These actions are important for shoulder movement and stability.
What is the origin of the External intercostals?
Inferior border of ribs
The External intercostals are vital for breathing.
What is the insertion of the External intercostals?
Superior border of ribs
This positioning allows them to elevate the rib cage.
What action do the External intercostals perform?
Elevates rib cage
This action is essential during inhalation.
