I'll leave this here:
https://legacy.etap.org/demo/biology_files/lesson6/instruction4tutor.html
Answer: The contracting cloud is then called a protostar. A protostar is the earliest stage of a star's life. A star is born when the gas and dust from a nebula become so hot that nuclear fusion starts.
Explanation:
Answer:
You have external defense systems, which include your skin, tears, mucus, saliva, stomach acid, cilia (small hairs) and helpful bacteria. The skin, nails and hair form the integumentary system, which stops dirt and pathogens from entering the body.
Uranium is not a fossil fuel.
<span>Prokaryotic cells and eukaryotic cells reproduce by mitotic cell division. Regardless of the type of cell, all cells must make a copy of their dna before they divide.</span>