D) Endocytosis is a transport mechanism that utilizes energy.
Endocytosis is an active transport, a biological process in which <span>molecules from outside the cell (proteins for example) are passed through the cell membrane and put into the cell. This process requires energy.
The other transport mechanisms, osmosis, diffusion and facilitated diffusion are processes that do not utilize energy. </span>
If mitotic cell division is the only way a particular species of single-celled organism can reproduce, it is most likely that the rate of evolution in this species is slower than in one that reproduces sexually. This is asexual reproduction, which causes mutations in a population to accumulate and combine more slowly than sexual reproduction in a cell line, as the mutations would have to arise multiple times in one line, rather than a few separate times and then be allowed to combine sexually for the descendants to have those traits.
Cells are limited in size by their surface area and volume.
A cell does not possess a mouth, lungs and digestive system. Every process has to happen directly or indirectly through the cell membrane. The relationship between the volume of cell contents and the surface area of the cell membrane becomes the limiting factor in how big a cell gets to be.
If it gets too big it may starve due to lack of incoming nutrients, or poison itself because it can not get rid of waste rapidly enough.
I know some of them.
For instance, blood cells, nerve cells, sperm cells, and egg cells.
Smoking, sitting too long, ......................... are examples of RISK FACTORS that offset the wellness benefits of fitness program.
Fitness program has many benefits that improve one's health status, but these benefits may be hindered from manifesting if one is indulging in some habits or eating some kind of foods that are not beneficial to one's health. Such unhealthy habits and foods are termed risk factors. And these risks factors may increase the probability of one having some types of diseases in the future. <span />
