Answer:
T-tubules (transverse tubules)
Explanation:
T-tubules, also known as transverse tubules, are narrow tubes that are continuous with the sarcolemma (i.e., the cell membrane of striated muscle cells). In skeletal/cardiac muscle cells, T-tubules form invaginations of the sarcolemma that contain many ion channels involved in excitation-contraction (e-c) coupling of muscle cells. Thus, transverse tubules function to conduct the action potential from the cell membrane (sarcolemma) to the interior of the muscle cell.
It's not that common actually quite rare because gray eyes are less than 1 percent of the earth population. Being that blue eyes and black hair is considered genetically impossible gray eyes are lighter, which makes it even more most likely impossible.
Fun fact: 10,000 years ago blue eyes didn't exist they are a mutation and everyone with blue eyes is technically related.
Eliminate wastes produced by homeostasis.
the answer is A
Prokaryotic means no nucleus. remember pro rhymes with no.