1 Each muscle fibre ( muscle cell ) is covered by a plasma membrane sheath which is called the sarcolemma. 2  Tunnel-like extensions from the sarcolemma pass through the muscle fibre from one side of it to the other in transverse sections through the diameter of the fibre.keletal muscles consist of 100,000s of muscle cells (also known as muscle fibers) that perform the functions of the specific muscle of which they are a part.
Another leafy vegetable high in beta carotene in the form of vitamin A, kale has 478 milligrams of the nutrient and 20 calories per half cup serving. Kale recipes to try: â¢ Kale Chips. â¢ Roast Cod with Bacon, Potatoes, and Kale. â¢ Kale Salad with Glazed Onions and Cheddar.
Theyâre high in calcium, rich in iodine, loaded with antioxidants, and low in calories. If Vitamin A is a concern for your diet, just one cup of these greens provides over 100% of the daily recommended value. Serving Size (1 cup), 5589 IU of Vitamin A (112% DV), 25 calories.hese are foods that contain vitamin A or its precursor called beta-carotene. Animal foods contain vitamin A whereas no plant food provides vitamin A but instead they have beta-carotene which is converted to vitamin A in the liver.