Podcast
Questions and Answers
Which muscles are specifically involved with rib elevation during respiration?
Which muscles are specifically involved with rib elevation during respiration?
Which muscle is NOT innervated by the glossopharyngeal nerve?
Which muscle is NOT innervated by the glossopharyngeal nerve?
What is the primary function of the epaxial muscles mentioned in the content?
What is the primary function of the epaxial muscles mentioned in the content?
Which muscle group is formed by the muscles that lie dorsal to the vertebral column?
Which muscle group is formed by the muscles that lie dorsal to the vertebral column?
Signup and view all the answers
Which of the following muscles is innervated by the trigeminal nerve?
Which of the following muscles is innervated by the trigeminal nerve?
Signup and view all the answers
Which nerve innervates all the muscles formed from the first branchial arch?
Which nerve innervates all the muscles formed from the first branchial arch?
Signup and view all the answers
Which of the following muscles is innervated by the facial nerve?
Which of the following muscles is innervated by the facial nerve?
Signup and view all the answers
What is the only muscle associated with the third branchial arch?
What is the only muscle associated with the third branchial arch?
Signup and view all the answers
Which muscle is involved in mastication and innervated by the trigeminal nerve?
Which muscle is involved in mastication and innervated by the trigeminal nerve?
Signup and view all the answers
Which nerve innervates the muscles from the fourth and sixth branchial arches?
Which nerve innervates the muscles from the fourth and sixth branchial arches?
Signup and view all the answers
What type of muscle development does the digastric muscle exhibit?
What type of muscle development does the digastric muscle exhibit?
Signup and view all the answers
Which of these muscles is NOT derived from the branchial arches?
Which of these muscles is NOT derived from the branchial arches?
Signup and view all the answers
Which structure does NOT belong to the first branchial arch?
Which structure does NOT belong to the first branchial arch?
Signup and view all the answers
What role does the quadriceps femoris play when extending the knee joint?
What role does the quadriceps femoris play when extending the knee joint?
Signup and view all the answers
Which muscle acts as the antagonist during the extension of the forearm?
Which muscle acts as the antagonist during the extension of the forearm?
Signup and view all the answers
What is the primary function of a fixator muscle?
What is the primary function of a fixator muscle?
Signup and view all the answers
Which component comprises a motor unit?
Which component comprises a motor unit?
Signup and view all the answers
What happens to skeletal muscle fibers due to loss of motor innervation?
What happens to skeletal muscle fibers due to loss of motor innervation?
Signup and view all the answers
Which action is associated with the biceps brachii?
Which action is associated with the biceps brachii?
Signup and view all the answers
What is meant by muscle tone?
What is meant by muscle tone?
Signup and view all the answers
Which of the following best describes a synergist muscle?
Which of the following best describes a synergist muscle?
Signup and view all the answers
Which of the following accurately describes the function of the dorsal roots?
Which of the following accurately describes the function of the dorsal roots?
Signup and view all the answers
What is the primary consequence of disuse atrophy in muscles?
What is the primary consequence of disuse atrophy in muscles?
Signup and view all the answers
Which of the following statements about the structure of a mixed nerve is correct?
Which of the following statements about the structure of a mixed nerve is correct?
Signup and view all the answers
How are skeletal muscles named based on their function?
How are skeletal muscles named based on their function?
Signup and view all the answers
What characterizes the ventral roots of spinal nerves?
What characterizes the ventral roots of spinal nerves?
Signup and view all the answers
What does the mnemonic 'SAD DAVE' help to remember?
What does the mnemonic 'SAD DAVE' help to remember?
Signup and view all the answers
Which of the following terms refers to a muscle that increases the size of an opening?
Which of the following terms refers to a muscle that increases the size of an opening?
Signup and view all the answers
Which of the following describes the dorsal root ganglion?
Which of the following describes the dorsal root ganglion?
Signup and view all the answers
What does the term 'transverse' refer to in muscle naming?
What does the term 'transverse' refer to in muscle naming?
Signup and view all the answers
Which of the following muscle names indicates its depth?
Which of the following muscle names indicates its depth?
Signup and view all the answers
What does the name 'Latissimus dorsi' refer to?
What does the name 'Latissimus dorsi' refer to?
Signup and view all the answers
Which term is associated with muscles that have two origins?
Which term is associated with muscles that have two origins?
Signup and view all the answers
What aspect of muscle naming does the prefix 'Brachii' refer to?
What aspect of muscle naming does the prefix 'Brachii' refer to?
Signup and view all the answers
Which of the following correctly describes the muscles that are named based on size?
Which of the following correctly describes the muscles that are named based on size?
Signup and view all the answers
What does the term 'Superficialis' indicate regarding a muscle's position?
What does the term 'Superficialis' indicate regarding a muscle's position?
Signup and view all the answers
Which muscle name reflects its shape?
Which muscle name reflects its shape?
Signup and view all the answers
Study Notes
Branchiomeric Musculature
- First branchial arch muscles are innervated by the trigeminal nerve, including muscles of mastication, anterior belly of digastric, mylohyoid, tensor tympani, and tensor veli palatini.
- Second branchial arch muscles are innervated by the facial nerve, which includes muscles of facial expression, posterior belly of digastric, stylohyoid, and stapedius muscle.
- The only muscle from the third branchial arch is the stylopharyngeus, innervated by the glossopharyngeal nerve.
- Muscles from the fourth and sixth branchial arches are innervated by the vagus nerve, encompassing muscles of the palate (except tensor veli palatini), pharynx (except stylopharyngeus), and larynx.
Embryonic Development of Muscles
- Muscles originate from somite myotomes, specifically epaxial muscles, which are dorsal to the vertebral column.
- The epaxial group consists of transversospinalis, longissimus, and iliocostalis muscles, alongside levatores costarum involved in rib elevation during respiration.
Roles of Muscles in Movements
- Prime mover (agonist) is the main muscle responsible for a specific movement (e.g., triceps in forearm extension).
- Antagonist opposes the action of the prime mover (e.g., biceps brachii during extension).
- Synergists assist prime movers in their actions, while fixators stabilize the origin of prime movers through isometric contractions.
- Muscle tone refers to the partial contraction state of muscles at rest.
Motor Unit
- A motor unit consists of a motor neuron and all muscle fibers it innervates.
- Importance of nerve supply: Loss of motor innervation leads to rapid muscle fiber degeneration and atrophy, observable within hours of denervation.
Disuse Atrophy
- Disuse atrophy is a physiological response to not using muscles enough, leading to decreased size and strength.
- The principle mnemonic for spinal cord anatomy states: Sensory = Afferent = Dorsal; Efferent = Ventral.
Innervation of Skeletal Muscle
- Each skeletal muscle is supplied by one or more mixed nerves (60% motor, 40% sensory), including sympathetic fibers.
Bases of Nomenclature of Muscles
- Muscle names are often based on action, direction of fibers, attachments, depth, position, number of heads, size, and shape.
- Examples of action-based naming include deltoid (triangular), quadratus (square), and rhomboid (diamond).
- Fiber direction can be described as rectus (straight), obliques (angled), and transverse (horizontal).
- Notable examples of attachment: sternocleidomastoid (SCM) and coracobrachialis.
- Intrinsic muscles are shaped and named according to their form.
- Size distinctions may have terms like major, minor, and specific identifiers for size in muscle names, such as gluteus maximus, medius, and minimus.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on the generalities of muscle tissues, specifically focusing on branchiomeric musculature. This quiz covers the essential concepts and innervation of muscles arising from the first branchial arch, as discussed in the lecture prepared by Tubat, Campos, De Jose, and Valiente.
