Answer:
B) Na+
Explanation: Na+ molecule is polar, oxygen and carbon dioxide are nonpolar molecules. The cell membrane is a <em>phospholipid bilayer</em> made up of lipid molecules with polar and nonpolar ends. Since it is a bilayer, two phospholipid layers are arranged, one on the other in such a way that one faces the back of the other. The non polar ends are away from outside and inside of the cell, while the polar ends faces towards all the molecules inside and outside the cell.
Since polar-polar molecules repel each other, Na+ can't pass through the cell membrane easily. So it uses the proteins attached the cell membrane inside and outside to transport such molecules by using energy in terms of ATP.
Answer:
The answers would be likely be to a.) improve the environment and b.) cut costs.
1. Multicellular
2. Multicellular, tissues, bilateral symmetry, body cavity, coelom, segmentation, jointed appendages, exoskeleton
3. Annelids
4.Jointed appendages, exoskeleton
5. Evolutionary phylogeny is unknown, but it is known to have some of these adaptive traits (multicellular, tissues, bilateral sym, body cavities, coelom)
6.sponges, jellyfish, roundworms, snails
Answer:
ion even know what this means
Explanation:
