The 3 Basic Parts of all Cells

1. Plasma Membrane

2. Cytoplasm

3. Nucleus or Nuclear Area

Classes of Cells

• Two basic types of cells:1. Prokaryotic cells

2. Eukaryotic cells

Eukaryotic cells Animal Cell

Fig 4.6

Eukaryotic Cell Structure

1. Nucleus:

2. Smooth Endoplasmic Reticulum:

3. Ribosomes:

Site of protein synthesis

Eukaryotic Cell Structure4. Rough Endoplasmic Reticulum:

-

5. Golgi Apparatus:

6. Vesicles: Membrane-bound “balloons” that transport and store substances in cells

Eukaryotic Cell Structure7. Lysosomes:

8. Cytoskeleton:

9. Mitochondria: – Harvest energy from organic molecules (e.g.

sugars and fats) to produce ATP– Has own DNA & divides on own

Plant Cell –Fig. 4.6b

Plant cells also have:1. Vacuole

2. Chloroplasts

3. Cell wallProtects, supports

**Plant cells do not have lysosomes

Transporting across membranes• Solvent – • Solute –

• Selectively permeable – water can move freely through the membrane, but the membrane regulates the passage of solutes

• Diffusion – movement of molecules from an area of high concentration to an area of low concentration

• Osmosis – movement of water across a selectively permeable membrane.

Given a membrane that is permeable to water and glucose:

Which way will water move?

Which way will glucose move?

• Water acts to dilute!!• Hypertonic –

• Hypotonic –

• Isotonic – equal solute concentrations on both sides of the membrane

Fig. 5.12: Diffusion

Isotonic Solutions

Fig. 5.13

Fig. 5.14