<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>
<h3><u>Answer;</u></h3>
A. Gas exchanges takes place by diffusion.
B. It is an open system.
<h3><u>Explanation</u>;</h3>
- Most molluscs and arthropods have an open type of circulatory system.
- Open circulatory systems pump blood into a hemocoel with the blood diffusing back to the circulatory system between cells.
- Blood is pumped by a heart into the body cavities, where tissues are surrounded by the blood.
<span>The best set of materials to prepare a wet mount slide of onion skin cells are as follows:
a glass slide, stain, forceps, dropper, a toothpick, and a beaker filled halfway with water.</span>
