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.
Liver, whole or fortified milk and milk products contain vitamin A. Leafy green vegetables such as spinach, broccoli and brussels sprouts as well as yellow and orange fruits and vegetables such as cantaloupe, carrots, sweet potatoes and squash contain beta-carotene, which converts to vitamin A in the body.he fat-soluble vitamins A, D, E and K are found in many foods, do not easily get lost in cooking and digest better when accompanied by fat. They are needed in only small amounts, and the excess is stored in the liver and fat tissues, so healthy persons need not consume them in food every day.