Not to be confused with Retinal. Retinol, also known as Vitamin A1, is a vitamin found in food and used as a dietary supplement. As a supplement it is used to treat and prevent vitamin A deficiency, especially that which is resulting in xerophthalmia.
Desmosomes are anchoring junctions â mechanical couplings scattered like rivets along the sides of adjacent cells to prevent their separation. On the cytoplasmic face of each plasma membrane is a thickening called a plaque.
1. All-or-None Law-Gap junctions allow all cardiac muscle cells to be linked electrochemically, so that activation of a small group of cells spreads like a wave throughout the entire heart. This is essential for synchronistic contraction of the heart as opposed to skeletal muscle. 2. Automicity (Autorhythmicity) - some cardiac muscle cells are self-excitable allowing for rhythmic waves of contraction to adjacent cells throughout the heart.