10-1 Cell Growth

Limits To Growth The larger a cell becomes, the more demands the cell places on it DNA and the more trouble the cell has moving enough nutrients and waste across the cell membrane

DNA Overload The DNA of small cells is able to meet all the cell’s needs As a cell increases in size it DOES NOT make more DNA Example:  Lunch at LSW  If 500 more students went to 5 th lunch shift and no additional food were prepared what would happen?

Exchanging Materials Food, water, & oxygen enter the cell through the cell membrane Waste leaves the cell through the cell membrane The cell’s surface area (total area of cell membrane) determines the rate of exchange across the membrane The cell’s volume determines the rate of waste production and food/water use.

Ratio of Surface Area to Volume Volume increase more rapidly then surface area Causing the volume to surface area ratio to decrease Results in problems for the cell Example:  School halls- if the population of students at LSW doubled but we did not increase the size of the school what would the halls be like?

Cell Size Surface Area (length x width x 6) Volume (length x width x height) Ratio of Surface Area to Volume

Cell Division The process by which a cell divides into two daughter cells The DNA replicates before division Each new cells gets a complete copy of DNA Daughter cells are identical