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.
Shop Sofas 1  â¸. Sectional: Sectional sofas have gained popularity in recent years because they can be set up in a wide variety of ways. 2  Sleeper: Sleeper sofas are popular because they are dual-purpose. 3  Loveseat: Usually part of a set, the loveseat sofa is one of the most popular types of living room furniture. Loveseats are fashionable because they offer added seating but don't take up as much room as a traditional sofa. Loveseats are designed for a maximum of two people.