Microscopic Muscle Anatomy Flashcards
What do skeletal muscles do?
connect to bones in your body and facilitate movement
List the order of the muscle from big to small
muscle, fascile, myocyte, myofibril, sarcomere
What is a tendon?
connects skeletal muscle to skeleton
What is epimysium?
connective tissue that surrounds the whole muscle
What is a fasicle?
smaller units in whole muscle that holds muscle cells
What is perimysium?
connective tissue that surrounds the fascicle
What is endomysium?
connective tissue that surrounds each myocyte
What is a myocyte?
a muscle cell = a muscle fiber
What is a myofibril?
a long string/line inside of a muscle cell, that has sarcomeres from end to end
What is a sarcomere?
a contractile unit of a myofibril
Does the body create more myocytes?
No
What does the body do to grow?
It adds more myofibrils and sarcomeres
What is hypertrophy? What happens to myofibrils?
enlargement of tissue when cells get bigger; myofibrils get more dense
What is hyperplasia? What happens to myofibrils?
enlargement of tissue when the number of cells increase; more myofirbrils get added
What are tendons mostly made of?
collagen
What can tendons do across rough bone projections?
Slide
What is a common tendon? What does it connect?
Achilles tendon; connects calf muscles (gastroc and soleus) to heel (calcaneous)
What are the two regions of a sarcomere?
Thin and thick filament
What does thin filament connect to, and what does it have?
Z-line and actin
What does thick filament connect to, and what does it have?
m-line, and myosin
What does myosin do? What does it use?
Myosin grabs onto actin and pulls it; it uses one ATP molecule per step
What runs along the thin filament?
tropomyosin and troponin
What blocks the active site on thin filament?
tropomyosin
What binds to what on the thin filament? What does this do and allow?
Calcium binds to troponin, which moves tropomyosin, and allows the myosin to bind to the active site, and move actin
