Transverse tubules. - tubules formed by invaginations of the sarcolemma and flanked by the sarcoplasmic reticulum, they carry action potentials deep into the muscle fiber. T tubules and SR provide tightly linked signals for muscle contraction. T tubules at each A band/I band junction-continuous with the sarcolemma.
Standard Sizes of Sofas. Sofas vary in size, from 6 to 8 feet long and 32 to 40 inches deep for a standard size sofa, to 4 to 6 feet long and 28 to 30 inches deep for a loveseat.The actual depth of the seating area is reduced by the depth of the sofa's arms and back of the sofa.ofas vary in size, from 6 to 8 feet long and 32 to 40 inches deep for a standard size sofa, to 4 to 6 feet long and 28 to 30 inches deep for a loveseat.
The twin size or compact version is 45 to 51 inches long from arm to arm. The height and depth is usually 28 inches. While compact, this is sufficient for two people. The full size version naturally has more space. The small standard length is at least 52 inches. The medium standard is 64 inches. The 71 inch measurement is reserved for a loveseat sofa. The height varies, but 36 inches is commonplace.