Cell Structure 7.2

3 Main Parts of Cell (1) Membrane - Functions: * controls what enters/exits cell * protects cell * supports cell

- parts: * Lipid - made of 2 layers of phospholipids = lipid bilayer - each lipid  polar head (hydrophilic) & 2 nonpolar tails (hydrophobic)

- Polar heads oriented to be near water

* Proteins embedded within lipid bilayer - markers – identify - channels – passageways - receptors – receive & transmit info * Carbohydrates attached to proteins (to ID)

Fluid Mosaic Model

- Fluid mosaic – made of many parts which can move laterally within bilayer - Selectively permeable = some things can pass through, others cannot

(2) Nucleus - Functions: * contain DNA (= control center)

- Parts: * nuclear envelope (2 membranes) * nuclear pores (holes) * chromosomes (condensed) / chromatin (loose) * nucleolus – makes ribosomes

(3) Cytoplasm - Functions: * holds organelles - space b/t membrane & nucleus

Eukaryotic Cell Types PLANT ANIMAL

Eukaryotic Cell Types PLANT - cell wall ANIMAL - no cell wall

Eukaryotic Cell Types PLANT - cell wall - plastids (chloroplasts) ANIMAL - no cell wall - no plastids

Eukaryotic Cell Types PLANT - cell wall - plastids (chloroplasts) - one, large central vacuole ANIMAL - no cell wall - no plastids - many, small vacuoles

Eukaryotic Cell Types PLANT - cell wall - plastids (chloroplasts) - one, large central vacuole - no centrioles ANIMAL - no cell wall - no plastids - many, small vacuoles - centrioles