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.
Question 3 is a scientific question because it can be experimented and answered by science.
Hope that helps!
What do mitochondria do? Where are they found?
They harvest chemical energy from food & carry out cellular respiration, the conversion glucose to ATP. They are found in cells of eukaryotes, except a few anaerobic protozoans. The ATP generating electron transport system is embedded in the inner membrane (cristae) and chemical reactions occur in compartments between membranes.
What are the functional categories of organelles?
Eukaryotic organelles comprise four functional categories: -manufacture (synthesis of macromolecules and transport within the cell), -breakdown (elimination and recycling of cellular materials - energy processing (conversion of energy from one form to another) -support, movement, and communication (maintenance of cell shape, anchorage, and movement of organelles, and relationships with extracellular environments) All four categories work together as an integrated team, producing the emergent properties at the cellular level.
So in smaller terms, I guess eukaryotic organelles do this.
