Unit 2: Topic 3 - Cell Size Flashcards
How does the surface area-to-volume ratio of a cell affect the cell?
Cells with higher surface area to volume ratios are more effective at transporting through materials and energy since there is more surface area for transport and energy transfer to happen per unit of volume.
What is surface area to volume ratio of a sphere with a radius of 5 cm?
Surface area of a sphere = 4π(r^2) Volume of a sphere = (4/3)π(r^3) These formulas are given on the AP exam so you do not need to memorize them. The surface area to volume ratio is equal to surface area divided by volume. So for a sphere it would be equal to 4π(r^2)/(4/3)π(r^3) Then plug in r=5 to find the surface area to volume ratio of 3/5
What is the major reason as to why cells are more efficient at smaller sizes?
Cells tend to be small because a smaller radius means a higher surface area-to-volume ratio. A higher surface area-to-volume ratio means the cell will more efficiently transport energy and materials in and out of the cell. A cell with a larger radius would have a smaller surface area to volume ratio and be unable to efficiently transport energy and materials, which means that it would be less efficient at maintaining homeostasis.
Why does the inner membrane of the mitchondria have folds?
It is folded to increase the surface area of the membrane, which increases the area where reactions can happen to generate ATP
Why do cells tend to decrease in effeciency as they get larger?
As cells increase in size, the demand for resources and energy increases. Surface area increases but not as fast; volume is cubed, and surface area is squared. This means that larger cells have a smaller surface area-to-volume ratio, so they tend to need more resources but cannot get them as efficiently.
How do cells obtain nutrients and eliminate waste?
Cells obtain nutrients and eliminate wastes through various types of diffusion, membrane proteins, and organelles. For example, cells use organelles called lysosomes to break down waste and transport proteins for facilitated diffusion to control what diffuses into the cell.
