At the bottom is the common phospholipid ,phosphatidylcholine.lipids are a group of naturally occurring molecules the include fats ,waxes ,sterols ,fat-soluble vitamins.
<span>Answer: Bone marrow stem cells have been shown to generate cartilage, bone, and muscle when injected directly into the injured site
Stem cells could differentiate into the various type of cells, makes them able to regenerate part of the body that doesn't have regeneration abilities. The cell that involved the </span><span>tear of the rotator cuff would be cartilage, bone, and muscle. Stem cells could replace the damaged cells so that the muscle and joint might work better. </span>
Answer
Environmental pressures
Basically every animal adapts to pressures from their environment in different ways, causing them to have different shapes and sizes