Muscular System Flashcards
What is the order of the skeletal muscle structure from simple to complex
Muscle fiber(cell), Endomysium, Muscle Fascicle, Perimysium, Epimysium, Muscle Body`
Why do skeletal muscle cells have so many nuclei?
Essential for protein production
What are muscle cells made of?
Myofibrils
Lengthwise segments of myofibrils are
Sarcomeres
What is the perimysium?
Connective tissue layer around fascicle
What is the endomysium?
Deepest layer of connective tissue that surrounds individual fibrils
What is the epimysium?
Connective tissue that encases the entire muscle body
What are myofilaments?
Two different types of protein strands
What are the two myofilaments?
Actin and Myosin
Physical characteristics of Actin
Skinny
Physical characteristics of Myosin
Thick with golf club-like studded
What is Ca 2+ (Calcium ion) role in muscle contraction
Binds to Actin proteins to encourage Myosin head attachment to Actin strands
What are the two proteins entwined with the Actin?
Troponin and tropomyosin
Purpose of troponin and tropomyosin
Act as insulation of Actin to prevent Myosin heads from touching
What do myofibrils store?
Glycogen
What is the plasma membrane surrounding each muscle fiber called?
Sarcolemma
What happens to Muscle cell membrane when stimulus is applied
Becomes more permeable to sodium which diffuses inwards and makes inside positive
Describe Depolarization
Stimulus applied to membrane makes it permeable to sodium which allows it to diffuse inwards and make inside postive
Describe Repolarization:
Sodium channels close, Potassium channels open and K+ diffuses out of the cell. (Active Transport)
What happens when an impulse reaches the end of motor neuron?
Vesicles release acetylcholine into Synaptic cleft
What is the role of acetylcholine?
To stimulate receptors in the sarcolemma which will send the impulse to the T-tubules and into the sarcoplasmic reticulum
3 energy storage compounds located inside the muscle
- Myoglobin
- Glycogen
- Fatty acids
3 organs that generate creatine phosphate
- Liver
- Kidneys
- Pancreas