Explanation:
Simple Diffusion across the Cell (Plasma) Membrane The structure of the lipid bilayer allows only small, non-polar substances such as oxygen and carbon dioxide to pass through the cell membrane, down their concentration gradient, by simple diffusion.
Living things require specific organic molecules in order to survive. The picture above represents some specific examples of foods that are mainly composed of one of these necessary organic molecules. The organic molecules found in these types of food are
B) proteins.
There are four principles at work in evolution—variation, inheritance, selection and time. The theory of evolution by natural selection, first formulated in Darwin's book "On the Origin of Species" in 1859, is the process by which organisms change over time as a result of changes in heritable physical or behavioral traits.
