Arrange the following words from smallest to largest:

1. Arrange the following words from smallest to largest: Earth , New York, North America, Long Island, Northern Hemisphere, Floral park http://htwins.net/scale2/?bordercolor=white

2. ANSWER: FPM, LI, NY, North America, Northern Hemisphere, Earth Living things contain: tissues organs cells systems

4. • The smallest unit of an element that maintains the chemical property of the element. • An element is only one kind of atom or atoms ex.) ▫ Carbon (C) ▫ Hydrogen (H) ▫ Nitrogen (N) ▫ Oxygen (O)

5. • A group of atoms that are held together by chemical forces (bonds). • Water molecule

6. •Basic unit of structure and function in living things •Carry out life processes •Different types

7. A group of similar cells that work together to perform the same function

8. A group of similar tissues that work together to perform the same function

9. A group of different organs that work together to perform the same function

10. Review • Which sequence shows a increasing level of complexity? 1. organs -> organism -> cells -> tissue 2. organism -> cells -> organs -> tissues 3. cells-> tissues -> organs -> organism 4. tissue -> cell -> organism -> organ

11. Review cells cell X organ Tissue Organ X X= tissue X= Organ system or Organism

12. How do we know cells exist? Development of the Cell Theory

13. Robert Hooke •Observed slices of cork with a comp. microscope (1600’s)

14. • Saw hollow spaces  called them “CELLS” • What he saw was only walls of dead cells (cork = dried out plant cells)

15. Anton van Leeuwenhoek•1600’s •Used a simple microscope •First to look at living cells

17. •Observed 1 celled organisms (bacteria, protists…) •Rain pond water, the mouth, intestines

18. •Observed plant cells •All plants are made of cells Matthias Schleidan (1800’s)

19. Theodor Schwann (1800’s) •Observed animal cells •All animals are made of cells

20. Robert Virchow (1800’s) •All cells are made from pre-existing cells. •All cells come from other cells. •(Cells divide  more cells)

21. Cell Theory • 1. Cells are the basic unit of structure in all living things. • (Living things are made of cells)

22. Cellular Diversity Cellular Diversity

23. •2. Cells are the basic unit of function of all living things •(They carry out life processes)

24. All living things are made up of cells. • Cells allow living things to obtain and use energy! • An organism uses this energy to perform all the life functions it needs to survive. • What are the life functions?

25. Life Functions •Transport •Growth •Locomotion •Respiration •Excretion •Regulation •Reproduction •Synthesis •Metabolism •Nutrition

26. • 3. All cells come from pre- existing cells.

27. •1. Viruses are NOT cells, and are NOT made of cells. Exceptions to the Cell Theory

28. Virus do not reproduce by division because they are not cells.

29. • 2. Mitochondria & Chloroplasts • cell parts that have own DNA and reproduce on their own. • (Don’t need the nucleus to reproduce)

31. •3. The first cell could not have come from a pre- existing cell.

32. Summary: • State ways in which a single cell organism, such as an ameba, and a human body cell are alike. 1.) They contain similar structures (organelles) 2.) They are the basic unit that performs life function for the organism

33. DO NOW: What should the “?” be?

34. Organelles • Structures that are found in the cell that perform all cell activities • a.k.a cell parts