Answer;
-Pectinate muscles
Explanation;
-Pectinate muscles are shaped a little like hair, and their function is maxium atrial contraction with minimal muscle mass.The pectinate muscles (musculi pectinati) are parallel ridges in the walls of the atria of the heart. They are so-called because of their resemblance to the teeth of a comb as in pecten.
-The pectinate muscles are ridge like elevations of muscle. They are parallel to each other and resemble teeth of a comb. They are easily observed inside the right atrium.
Answer:
Just look up each of those words and their stages. This will surley find you your answer!!
Yes, the cell membrane regulates what enters the cell and leaves the cell. The cell membrane is a fluid mosaic consisting of a phospholipid bilayer and integral and peripheral proteins. The proteins of the membrane serve many purposes: transport, receptors, etc. The cell membrane is amphipathic, meaning is has hydrophilic and hydrophobic regions.
Electrical energy is energy derived from electric potential energy or kinetic energy. So D would be the best answer
To answer your question: the nucleus has a membrane.