Muscular System Flashcards
(34 cards)
Skeletal Muscle
Function
Attaches to bones and are largely responsible for voluntary (you can move them) body movements
Structure
Striated muscle: Made of striation
Smooth Muscle
Structure
Small, spindle-shaped, non-striated
Involuntary (not under conscious control) and have a single nucleus
Function
Cells are arranged in layers, the alternate contracting and and relaxing of these layers changes the size and the shape of the organ and aid in moving the contents of the organ
Can sustain contraction for long periods of time without fatigue
Cardiac Muscle
Location
Located solely in the walls of the heart
Structure
Branched and cross striated cells that join together at structures called intercalated discs
Function
The arrangement of cells enables spontaneous contractions of neighboring cells to produce the heartbeat
Extensibility
the ability to be stretched
Elasticity
the ability to return to normal length after a stretch
Irritability
the ability to respond to stimulus. Muscles are stimulated from the nerves that supply then and results in muscle contraction
Contractility
the ability to contract and shorten. Most muscles have a tendon attached to a bone at one end and the same at the other end. When a muscle contracts, it pulls on the bone at the attachment sites. The pulling force is called tension.
Concentric
shortening of muscle (movement) C= moving towards the clouds
Eccentric
lengthening of muscle (movement) E= moving towards the Earth
Isometric
no change in muscle length (No movement)
Muscles generate heat
Muscles generate heat when they are worked
Muscles require ATP to function.
When a muscle is stimulated, ATP is released to provide energy for contraction,
heat is generated in the process
Skeletal Muscles
Muscular strength
determined by how much weight a muscle can lift
Muscle Endurance
the ability to continue contracting a muscle, or group of muscles, against resistance, such as weights or body weight, over a period of time.
Muscle Fatigue
Muscle soreness
When the body is providing as much oxygen to the cells as required your cells have no problem keeping up with aerobic respiration (when oxygen is used to make energy)
When you are requiring more energy than the oxygen you are taking in your cells being to go through anaerobic respiration (does not require oxygen to create energy)
A by product of anaerobic respiration is lactate allows muscle to continue contracting even when energy is depleted
When lactate can no longer provide energy. You have met your lactate threshold, causing soreness to preventing injury
Muscles Growth
After you workout, your body repairs or replaces damaged muscle fibers through a cellular process where muscle fibers are fused together to form new muscle protein strands or myofibrils
Muscles of the head and neck
Frontalis
Location: Forehead
Function: Raise eyebrows
Orbicularis Oculi
Location: around eyes
Function: Close eyes
Nasalis
Location: Nose
Function: modify size of nostrils
Orbicularis Oris
Location: Encircles Mouth
Functions: closes lips, kissing motion
Zygomaticus
Location: Connects cheekbones to corner of mouth
Function: smiling
Platysma
Location: Front and side of mouth
Function: pulls corners of mouth down, opens mouth wide
Masseter
Location: Connects cheekbones to corners of mouth
Function: Closes jaw
