Best Answer: Discrete, in this sense, means the opposite of continuous. An example of a continious variable would be the speed of a car. It can be anywhere ...
Most cells are small for two main reasons: a). The cellâs nucleus can only control a certain volume of active cytoplasm. b). Cells are limited in size by their surface area to volume ratio. A group of small cells has a. relatively larger surface area than a single large cell of the same volume. This is important. because the nutrients, oxygen, and other materials a cell requires must enter through it surface. As a. cell grows larger at some point its surface area becomes too small to allow these materials to enter. the cell quickly enough to meet the cell's need.
of cytoplasm contained within the cell membrane. from the membrane to the center of the cell by diffusion. there must be an adequate ratio between the cellâs surface area and its volume. simplest model of cell shape) gets larger, its volume increases at a different rate than its surface area. In this lab, we will investigate this relationship and how it affects diffusion time. The prime limitation to cell size is the limitation imposed by diffusion. Diffusion is a very slow process. If a cell were 20 cm (~8 inches), it would take days for nutrients to reach its center or for wastes to reach the cell membrane. The cell would quickly starve to death or poison itself with its own wastes. So whatâs the solution, if a cell approaches its maximum size? Itâs time to divide! If cells receive the proper signals, they will divide by mitosis before they become too big. PART 1 In this lab activity, you will use agar cubes as cell models.