OCEANO 1 Lecture Notes - Lecture 4: Threshold Voltage, Peripheral Nervous System, Perimysium
Document Summary
It is continuous with the connective tissue that covers the outermost layer of muscle: epimysium. Underneath the epimysium is another type of connective tissue: perimysium, which covers subunits of muscle tissue called fascicles. Within each of the fascicles there is another type of connective tissue: endomysium, which protects individual muscle cells: myofibres. A myofibre looks like a pipe with a couple of bumps in it. These can help replicate or produce more myofibres. The plasma membrane of the myofibres is called the sarcolemma. The myofibre has a bunch of smaller units within it, too: myofibrils, which is where the actual contractions take place. The striations of the myofibrils we can see under the microscope are called z- lines. The space between the z-lines is the sarcomere, most basic unit of contraction, here actin and myosin fibres interact. The a-band is in the middle of the sarcomere. The a-band consists of both actin and myosin.
