Muscle Movements
To produce a movement, a muscle's _____ _____ (2 words) always moves towards its _____ (1 word).
What are a muscle's INSERTION POINT and ORIGIN?
When hearing something behind you, this muscle allows you to look over your shoulder.
What is the sternocleidomastoid?
This is another term for skeletal muscle cell.
What is a myofiber?
This ______ ____ (2 words) is only found in cardiac muscle and contracts in a wave-like pattern allowing the heart to ____ (1 word).
What is intercalated disc and pump?
This smooth muscle found in the eye adjusts the lens.
What is the ciliary body?
An arabesque is a common ballet step in which an unbent leg is raised posteriorly. It is also this type of movement.
What is extension?
Without this muscle, we could not hug loved ones.
What is the pectoralis major?
Name a skeletal muscle that fuses into a tendon-like sheet called an aponeurosis.
What is the latissimus dorsi?
This cell structure in cardiac muscle anchors the fibers together so they do not pull apart under the stress of contraction.
What is a desmosome?
This is why smooth muscle does not appear striated.
What is they do not contain myofibrils composed of highly organized sacromeres?
Most ankle sprains are caused by this type of ankle movement due to weaker lateral ligaments.
What is inversion?
Without this muscle, you probably would have trouble in yoga class.
What is the internal abdominal oblique muscle?
These 2 skeletal muscle shapes are the strongest whereas this shape is considered the weakest.
What are convergent and pennate muscles and circular muscles?
True or False: Like skeletal muscle, calcium ions that initiate contraction in cardiac muscles are released by the sarcoplasmic reticulum. If false, name where they come from.
What is false as most calcium ions are from outside the cell?
Name three features that are unique to smooth muscle.
What are they are unstriated, spindle-shaped, and do not contain T tubules?
This type of movement allows you to bend your neck or body to the right or left side.
What is lateral flexion?
Organs in the abdominopelvic cavity depend on this muscle to protect them
What is the external abdominal oblique muscle?
This phenomenon occurs when all myofibers respond to an action potential.
What is high fidelity?
True or False: Gap junctions allow for electric coupling which is quick transmission of action potentials. If true, describe how it is done.
What is true? Gap junctions form channels between adjacent cardiac muscle fibers allowing the depolarizing current to travel from one cell to the next quickly leading to coordinated heart contractions.
Instead of sacromeres, smooth muscle myofilaments are anchored by ______ ______ (2 words) which are attached to the sacrolemma.
What are dense bodies?
When learning to perform a one-footed turn called a pirouette in ballet, beginners are often told to "close the door" with the laterally held arm to the curved arm held in front of the ribcage. Name the 2 arm movements that come to mind.
What are abduction and adduction?
Name 3 muscles involved in knee extension.
What is the rectus femoris, vastus lateralis, vastus medialis, and/or vastus intermedius?
Describe the 3 adaptations at the skeletal muscle synapse, or the neuromuscular junction (NMJ), that contribute to high fidelity.
What are:
1. higher amount of NT
2. greater number of receptors
3. glial insulation of the synapse?
Autorhythmicity is a feature of specialized cardiac cells called _______ _____ (2 words). They are able to depolarize and fire action potentials on their own.
What are pacemaker cells?
Calcium ions necessary for smooth muscle contractions are supplied by the _______ _______ (2 words) in the fibers as well as removed from extracellular fluid by membrane indentations called ______ (1 word).
What is the sacroplasmic reticulum and calveoli?