cell size + compartmentalisation Flashcards
What is the primary function of the plasma membrane in cells?
The plasma membrane facilitates the exchange of materials, including gases, food molecules, and waste products
What materials must cells absorb and eliminate?
Cells must absorb gases and food molecules dissolved in water and eliminate waste products
How does the surface area of a cell affect cell functions?
The size of the surface area limits the rate of exchange that can occur
What happens to a cell’s internal volume as it grows?
As a cell grows, its internal volume enlarges, requiring more service from the cell surface
Fill in the blank: The _______ limits the rate of exchange that can occur in a cell.
surface area
True or False: The internal regions of a cell do not need to be serviced by the cell surface.
False
What happens to the volume and surface area of a cell as it grows?
Volume increases more rapidly than surface area
Volume increases by the cube while surface area increases by the square.
How does the relative amount of surface area change as a cell grows?
It steadily decreases
This decrease affects the ability to pass materials to a unit volume of the cell.
As a cell grows, volume increases by the _______ while surface area increases by the _______.
cube; square
True or False: As a cell grows, the surface area increases more rapidly than the volume.
False
What happens to a cell as it grows larger?
Its surface area becomes too small to pass enough material to maintain life functions of the cell volume.
What must a cell do when its surface area to volume ratio becomes unfavorable?
The cell must divide into smaller cells or cease to function.
What is the key point regarding surface area to volume ratio as cells grow larger?
The surface area to volume ratio gets smaller as the cell gets larger.
How do large cells manage their internal environment?
They compartmentalise with organelles.
What is the benefit of cell compartmentalisation?
It maximises the ability to undertake different life processes under optimum conditions.
Which type of cells are typically larger: eukaryotic or prokaryotic?
Eukaryotic cells.
What do organelles provide for membrane-bound enzymes?
More space, increasing activity in cells.
How do organelles affect the exchange across the plasma membrane?
They reduce the amount of exchange that needs to occur.
What adaptation do intestinal epithelial cells have to increase surface area?
Microvilli, forming a ‘brush border’.
What is the shape of red blood cells and how does it benefit them?
Biconcave shape increases surface area to volume ratio for more efficient gas diffusion.
What is the size range of bacteria cells?
Around 0.1-0.5 µm long.
What is the typical size of human blood cells?
8 µm.
What is the typical size of plant cells?
100 µm.
What is the size of a paramecium?
About 250 µm.
