KEY CONCEPT Cells are the Basic unit of life.

1. KEY CONCEPT Cells are the Basic unit of life. Macrophages- play an important role in your immune system- take in a digest foreign materials (red= bacteria)

2. The cell theory grew out of the work of many scientists and improvements in the microscope. • Many scientists contributed to the cell theory. Concluded that ALL living things are made of cells Proposed that all cells come from other cells First to identify cells and named them Made better lenses for microscopes First to note that plants are made of cells

3. Robert Hooke • In 1665 he used the three-lens compound microscope to examine thin slices of cork • He observed that cork is made of tiny, hallow compartments • These compartments reminded Hooke of small rooms found in monasteries (where monks live), so he named them cells.

4. More was learned about cells as microscopes improved.

5. Cells Red blood cells cork

6. How does the size of a cell in a blue whale compare to the size of the cell in a tadpole?

7. How does the size of a cell in a blue whale compare to the size of the cell in a tadpole? A: Most cells in a whale are the same size as in a tadpole! So what makes a blue whale so much bigger? A whale has far more cells.

8. The Cell theory has three principles. 1. All organisms are made of cells.

9. 2. All existing cells are produced by other living cells.

10. 3. The cell is the most basic unit of life.

11. One of the 3 principles of cell theory is that ALL existing cells are produced by other existing cells. Apply this principle to a cut on your arm. (Explain what is happening throughout the healing process)

12. Answer One of the 3 principles of cell theory is that ALL existing cells are produced by other existing cells. Apply this principle to a cut on your arm. • You get a cut • You start to bleed • You form a scab • Messages are sent to skin cells to replicate • Skin cells replicate through mitosis • New skin cells are created • Scab falls off • You are healed!

13. cell membrane cytoplasm Bacterium (colored SEM; magnification 8800x) All cells share certain characteristics • Cells tend to be microscopic. • All cells are enclosed by a membrane. • All cells are filled with cytoplasm.

14. nucleus organelles cell membrane • There are two cell types: eukaryotic cells and prokaryotic cells. • Eukaryotic cells have a nucleus. • The nucleus holds the DNA • Have membrane-bound organelles • May be multi-cellular or single-celled organisms Draw and label picture on top of p. 24

15. Organelles: structures that are specialized to perform distinct processes within a cell. The nucleus is usually the largest and most visible organelle.

16. Things that have Eukaryotic Cells: PLANTS ANIMALS FUNGI

17. Bacterium (colored SEM; magnification 8800x) Cytoplasm: is a jellylike substance that contains dissolved molecular building blocks- such as proteins, nucleic acids, minerals, and ions

18. cytoplasm • Prokaryotic cells do not have a nucleus. • do not have membrane-bound organelles • DNA is in the cytoplasm • All are microscopic, single-celled organisms cell membrane Draw and label picture on top of p. 24

19. Things that have prokaryotic cells Archaea Bacteria

20. Viruses • Virus- An infective agent that typically consists of a DNA or RNA strand in a protein coat. • multiply onlywithin the living cells of a host • Antibiotics will not work on them • Vaccines prevent them Protein Coat EX: Herpes virus Influenza Chickenpox Ebola virus