Cardiac muscle (heart muscle). This type of muscle is found solely in the walls of the heart. It has similarities with skeletal muscles in that it is striated and with smooth muscles in that its contractions are not under conscious control. However this type of muscle is highly specialised.t has similarities with skeletal muscles in that it is striated and with smooth muscles in that its contractions are not under conscious control. However this type of muscle is highly specialised.
There are few natural sources of vitamin D. For that reason, most of the vitamin D in your diet comes from fortified foods, such as dairy products and alternatives, breakfast cereals, juices and margarine.
Vitamin D is a fat-soluble vitamin that is naturally present in very few foods, added to others, and available as a dietary supplement. It is also produced endogenously when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis.mall amounts of vitamin D are found in beef liver, cheese, and egg yolks. Vitamin D in these foods is primarily in the form of vitamin D 3 and its metabolite 25(OH)D 3 [ 12 ]. Some mushrooms provide vitamin D 2 in variable amounts [ 13, 14 ].