A research of the US National Institute of Health (NIH), <span>The use of calcium and vitamin D in the management of osteoporosis explained that 99% of the calcium that the body consumes goes to the bones and teeth. A lack of calcium and vitamin D will lead to bone thinning or osteoporosis which is told as a silent disease that deteriorates the bone. This tells that people should have enough calcium to keep the bones healthy and avoid some serious bone related problems because of calcium deficiency.</span>
C: replicate a gene without using bacteria
An unspecialized cell that can divide and give rise to different specialized cells is called a stem cell (Figure above). Zygotes and embryonic cells are both types of stem cells. These stem cells, called embryonic stem cells, can divide indefinitely and can specialize into any cell type. They are totipotent.
