Structure
What are the 3 types of muscles
Smooth, cardiac, skeletal
The light band contains only thin filaments which are comprised of what
Actin
Ability to recoil and resume resting length after stretching
Elasticity
General term for when muscles become weak and break down due to lack of use
Atrophy
List two of the four main functions of the muscular system
movement of the body
- maintaining posture
- generates body heat
role in other body systems
Individual muscle cells are separated by what
Fascia
The inner material of a muscle cell that functions similar to cytoplasm
Sarcoplasm
The neurotransmitter of skeletal muscles
acetylcholine
causes cholinesterase to not break down the acetylcholine in the synapse.
Tetanus
When exercising, if you go into an oxygen debt, what will be produced/accumulate in muscles
Lactic acid
Muscles are composed of many fibers that are arranged in bundles called what
Fascicles
What is the contractile unit of muscle cells
Sarcomere
What kind of ion rushes into muscle cells to generate action potential
Sodium
Why does rigor mortis occur
Lack of available ATP to unbind myosin heads
What are the reactants of cellular respiration (4)
Oxygen, glucose, pyruvic acid, fatty acids
List 4 main structural components of cardiac muscle
Striations
Usually has a single nucleus
Branching cells
Joined to another muscle cell at an intercalated disc
Involuntary
Found only in the heart
The folded portion within a neuromuscular junction where the muscle and neuron communicate
Motor end plate
In a relaxed muscle cell, the regulatory proteins forming part of the actin myofilaments
prevent myosin binding
Lowers the threshold level for an action potential, making it more likely the muscles will contract
Strychnine
What are the 3 cardiac biomarkers
Troponin
Myoglobin
Creatine Kinase
What type of connective tissue surrounds each individual muscle fiber
Endomysium
The bare zone on the muscle cell that lacks actin filaments is called what
H zone
What happens to calcium ions when action potential ends
They are reabsorbed into the SR storage areas, the regulatory proteins resume their original shape and position
Progressive neurodegenerative disease in which motor neurons stop sending messages to the muscles, causing atrophy
ALS
Autoimmune disease in which Acetylcholine receptors are damaged
Myasthenia Gravis