Move substances from one side of the cell membrane to the other
Answer:Their carbon skeletons are held together by covalent bonds
Explanation:They form the cells of an organism and perform the chemical reactions that facilitate life
Answer:
Cells provide six main functions. They provide structure and support, facilitate growth through mitosis, allow passive and active transport, produce energy, create metabolic reactions and aid in reproduction.
Explanation:
I think the answer is A or D
Explanation:
Larger lenses are heavier, and tend to sag under their own weight, ruining the image quality as the lenses distort. The long mounting tubes are hard to make mechanically stiff, and so they tend to flex under the weight of the lens, making it hard to keep the optics in alignment.
