D312 muscles: Questions with 100% correct
answers
What are the three types of muscle tissue?
- Skeletal: Voluntary, striated, moves bones
- Cardiac: Involuntary, striated, found in the heart
- Smooth: Involuntary, non-striated, found in internal organs
What are the different fascicular arrangements of muscles?
- Parallel: Fibers run parallel to the long axis
- Fusiform: Spindle-shaped with a wide middle and narrow ends
- Circular: Fibers arranged in a ring (e.g., sphincters)
- Pennate: Fibers arranged at an angle to the tendon
How are muscles named based on orientation?
- Oblique: Diagonal to midline
- Rectus: Parallel to midline
- Transverse: Perpendicular to midline
What do the following muscle names indicate about shape?
- Pectinate
- Platys
- Quadrate
- Deltoid
- Gracilis
- Piriformis
,- Rhomboid
- Serratus
- Pectinate: Comblike
- Platys: Flat
- Quadrate: Square-shaped
- Deltoid: Triangular
- Gracilis: Slender
- Piriformis: Pear-shaped
- Rhomboid: Diamond-shaped
- Serratus: Saw-toothed
How are muscles named based on action?
By the movement they produce, e.g., flexor (bends), extensor (straightens), adductor (brings
toward midline)
How are muscles named based on location?
By the body region where they are found (e.g., tibialis anterior is located on the front of the tibia)
How are muscles named based on origin and insertion?
By the bones they attach to (e.g., sternocleidomastoid originates at the sternum and clavicle,
inserts at the mastoid process)
What is a lever system?
A mechanical system where a force moves a load around a fulcrum
How do muscles act as levers?
, Muscles apply force to bones, which act as levers to move the body
What are agonist and antagonist muscles?
- Agonist: Prime mover, responsible for action - Antagonist: Opposes the agonist to control
movement
What are muscle compartments?
Groups of muscles enclosed by fascia that share similar functions
What are the components of cardiac muscle?
Intercalated discs, striations, single nucleus
What are the components of smooth muscle?
No striations, spindle-shaped cells, single nucleus
What forms skeletal muscle?
Muscle fibers, connective tissue, blood vessels, nerves
What is a sarcomere?
The functional unit of muscle contraction, composed of actin and myosin
What is the function of actin and myosin?
They interact to produce muscle contraction
What is the function of tropomyosin and troponin?
They regulate the binding of myosin to actin
What are the steps of muscle contraction?
answers
What are the three types of muscle tissue?
- Skeletal: Voluntary, striated, moves bones
- Cardiac: Involuntary, striated, found in the heart
- Smooth: Involuntary, non-striated, found in internal organs
What are the different fascicular arrangements of muscles?
- Parallel: Fibers run parallel to the long axis
- Fusiform: Spindle-shaped with a wide middle and narrow ends
- Circular: Fibers arranged in a ring (e.g., sphincters)
- Pennate: Fibers arranged at an angle to the tendon
How are muscles named based on orientation?
- Oblique: Diagonal to midline
- Rectus: Parallel to midline
- Transverse: Perpendicular to midline
What do the following muscle names indicate about shape?
- Pectinate
- Platys
- Quadrate
- Deltoid
- Gracilis
- Piriformis
,- Rhomboid
- Serratus
- Pectinate: Comblike
- Platys: Flat
- Quadrate: Square-shaped
- Deltoid: Triangular
- Gracilis: Slender
- Piriformis: Pear-shaped
- Rhomboid: Diamond-shaped
- Serratus: Saw-toothed
How are muscles named based on action?
By the movement they produce, e.g., flexor (bends), extensor (straightens), adductor (brings
toward midline)
How are muscles named based on location?
By the body region where they are found (e.g., tibialis anterior is located on the front of the tibia)
How are muscles named based on origin and insertion?
By the bones they attach to (e.g., sternocleidomastoid originates at the sternum and clavicle,
inserts at the mastoid process)
What is a lever system?
A mechanical system where a force moves a load around a fulcrum
How do muscles act as levers?
, Muscles apply force to bones, which act as levers to move the body
What are agonist and antagonist muscles?
- Agonist: Prime mover, responsible for action - Antagonist: Opposes the agonist to control
movement
What are muscle compartments?
Groups of muscles enclosed by fascia that share similar functions
What are the components of cardiac muscle?
Intercalated discs, striations, single nucleus
What are the components of smooth muscle?
No striations, spindle-shaped cells, single nucleus
What forms skeletal muscle?
Muscle fibers, connective tissue, blood vessels, nerves
What is a sarcomere?
The functional unit of muscle contraction, composed of actin and myosin
What is the function of actin and myosin?
They interact to produce muscle contraction
What is the function of tropomyosin and troponin?
They regulate the binding of myosin to actin
What are the steps of muscle contraction?
