Cell Sizes Growth Limitations EQ What factors controls

Cell Sizes & Growth Limitations

EQ: What factors controls or limit the Cell Size? 1. Diffusion limits size 2. DNA content limits size 3. Surface area to volume ratio limits size

EQ: What controls…Cell Size and Limitations 1) D_______ limits size 2) DNA content limits ____ 3) Surface a______ to v______ ratio limits size

How does Diffusion limit cell size? An oxygen molecule follows a path to the mitochondria (Oxygen)… plasma membrane cytoplasm mitochondria Smaller size allows the cell to be more efficient •

EQ: How does Diffusion limits size? (1) • An oxygen molecule follows a path to the mitochondria. • Oxygen (O 2) …. moves from outside the cell through the… pl_______ m_____ to the ( ) c_________m m_________ia • S______ size allows the cell to be more e_______.

EQ: How does DNA content limits size? • Cells usually contain only one nucleus • DNA • RNA • DNA is found in the nucleus makes RNA will travel through the cytoplasm to the ribosomes assists the ribosomes in making proteins is responsible for the whole above process • If the cell was very large, there would not be enough DNA to support the cell.

EQ: How does DNA content limits size? (2) *if the cell was a very _____size, there would not be enough _____ to support the cell.

EQ: How does DNA content limits size? • Cells usually contain only ______ nucleus -_______ is found in the nucleus - DNA makes ________ -RNA will travel through the c______ to the r_______ • RNA assists the ri______s in making p_______. • _____ is responsible for the whole above process

EQ: How does Surface area to volume ratio limits cell size • As a cell increases, it volume increases much faster than its surface area • If a cell doubled, the cell would require 8 X more nutrients and have 8 X more waste to get rid of ØFYI – If E. coli were left unreglated, it could engulf the Earth in one day because it doubles in volume every 30 minutes!!

EQ: How does surface area to volume ratio limits size? • As a cell i_____in size, the volume increases much faster than its S________ area

EQ: When do cells divide? • All organisms grow and change. • Cells are constantly growing, dividing, and dying • Some cells divide more than others – • Heart & nerve system cells rarely (if ever) divide • Skin cells, on the other hand, are constantly dividing • Growth is related to cell specificity and activity • If cell growth is uncontrolled – leads to cancer

EQ: When do cells divide? All organisms g______ and c____ • Cells are constantly growing, d____, and d_____ • • Some cells divide more than others – • G_____ is related to cell specificity and activity • If cell growth is uncontrolled – leads to c______