02Cells11Sp-1 - Biology 6B 02 Tour of the Cell Chapter 6: A...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Chapter 6: A Tour of the Cell Intro to Cells The importance of size A tour of the cell: organelles Cells have: What is a cell? Plasma membrane Cytoplasm DNA Enzymes Eukaryotic cells: 10-100 μ m Prokaryotic cells: 1-10 μ m Cells are small Why aren’t cells bigger? Surface area to volume ratio. Smaller cells have hgher ratio of surface area to volume. Why aren’t cells bigger? Surface area to volume ratio. Big cells don’t have enough surface area to feed the volume. Biology 6B 02 Tour of the Cell Brian McCauley Spring 2011
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 Why aren’t cells bigger? Diffusion distance Volume controlled by nucleus. Why aren’t cells bigger? Surface area to volume ratio. Volume controlled by nucleus. Upper limits on cell size are set by diffusion. Molecules must diffuse through cell. Why aren’t cells smaller? They must be big enough to hold all their parts! Macromolecules can’t be shrunk. eubacteria archaea eukarya No nucleus Small Unicellular No endo- membranes Prokaryotes Escherichia coli Prokaryotes lack a true endomembrane system The plasma membrane is the only membrane. Photosynthetic prokaryote Biology 6B 02 Tour of the Cell Brian McCauley Spring 2011
Background image of page 2
3 Life’s Family Tree eubacteria archaea eukarya Why no multicellular prokaryotes? Eukaryotic cells
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/02/2011 for the course BIOL 6a taught by Professor Staff during the Fall '10 term at DeAnza College.

Page1 / 11

02Cells11Sp-1 - Biology 6B 02 Tour of the Cell Chapter 6: A...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online