Exploring the World of Cells and Organisms

1. Cells

2. Cells • Definition: A membrane covered structure that contains all of the materials necessary for life. • Examples: Bone cell, blood cell, skin cell

3. Tissues • Definition: A group of cells that work together to perform a specific job in the body • Examples: Blood, fat, muscle

4. Organ • Definition: a group of tissues that work together. • Examples: Heart, lungs, skin • Skin is the largest organ!

5. Organ System • Definition: a group of organs that work together • Examples: digestive system, respiratory system, excretory system

6. Think about it…. Cells are related to tissues in the same way that organs are related to organ systems.

7. Organism • Definition: Anything that can live on its own • Examples: Lions, Tigers, and Bears, oh my!

8. Two Types of Cells: Prokaryotic Cell: Does NOT have a nucleus or any other membrane covered organelles, example bacteria. Eukaryotic Cell: Describes a cell that DOES have nucleus. Multi-cellular organisms have eukaryotic cells.

9. Unicellular Organism – single celled organism Multicellular Organism – more then one celled organism How do the cells of unicellular organisms differ from the cells of multicellular organisms? The cells of unicellular organisms can survive on their own, but the cells of multi-cellular organisms must remain a part of an organisms body to survive.

11. THE DISCOVERY OF CELLS

12. 1. Robert Hooke saw the first cork cell using a compound microscope.

13. 2. What are the three parts of the Cell Theory? • All organisms are composed of one or more cells • The cell is the basic unit of life in all living things • All cells come from existing cells

14. 3. All cells have • Cell membrane • DNA • Cytoplasm 4. Advantages to being multicellular • Grow larger • Have cells that are specialized for different tasks

15. 5. What are organelles? Structures within a cell that enables the cell to live, grow, and reproduce. 6. What is the cytoplasm? Fluid within a cell

16. 7. What is the function of the cell membrane? Acts as a barrier between the inside of the cell and its environment. 8. What is DNA? Hereditary material

17. 9. Why do all cells need DNA? DNA controls all of the activities of a cell and contains the information needed to make new cells. 10. What organelle is DNA enclosed inside of? The nucleus

18. 11. How are eukaryotic cells and prokaryotic cells different? Eukaryotic -has a nucleus -membrane-bound organelles -all other cells! Prokaryotic -NO nucleus -NO membrane-bound organelles -Bacteria is an example

19. Cell Parts and Their Function Cell Wall Function: Provides strength and support • Found ONLY in Plant Cells

20. Cell Membrane • Controls what enters and leaves a cell • Found in both plant and animal cells Nucleus • Controls cell activities • Found in both plant and animal cells Nuclear Membrane • Controls what enters and leaves a nucleus • Found in both plant and animal cells

21. Chromosomes • Carry the information used to run the cell; pass on traits to new cells • Found in both plant and animal cells

22. Nucleolus • Makes ribosomes • Found in both plant and animal cells

23. Endoplasmic Reticulum • Makes lipids & transports proteins and other materials through the cell • Found in both plant and animal cells Ribosome • Makes protein • Found in both plant and animal cells

24. Mitochondria • Supply the cell with energy (ATP is made here.) Cellular respiration occurs here. • Found in both plant and animal cells

25. Vacuoles • Stores food, water, and waste • Found in both plant and animal cells

26. Lysosomes • Contain enzymes that digest food • Animal Cells ONLY

27. Chloroplasts • Contain the chlorophyll needed to carry on photosynthesis (produce food) • Plant Cells ONLY

28. Cytoplasm • Liquid portion of the cell containing all the organelles • Found in both plant and animal cells

29. Golgi Complex • Processes and transports materials out of the cell • Found in both plant and animal cells

30. ANIMAL Nucleolus Chromosomes Nucleus Mitochondria Ribosomes Vacuole Nuclear membrane Endoplasmic Reticulum Golgi complex Cell Membrane Cytoplasm Lysosome**

31. PLANT Nucleolus Mitochondria Nuclear Membrane Nucleus Endoplasmic Reticulum Cytoplasm Cell membrane Chromosomes Cell Wall ** Golgi Complex Ribosomes Chloroplast ** Vacuole

32. Movement of Particles Into and Out of the Cell

33. Diffusion • DIFFUSION is the movement of particles from an area of high concentration (crowded) to an area of low concentration (less crowded) • Occurs with and between cells • Do NOT need energy (ATP)

34. In the body:

35. Osmosis • Diffusion of water through the semi-permeable cell membrane. • Semi-permeable-only certain substances can pass through • NO energyrequired • Can also occur in plant cells

36. Small Particle Movement • PASSIVE TRANSPORT - movement across the cell membrane withoutthe use of energy • movement is from an area of high to lowconcentration • Does NOTrequire energy

37. PASSIVE TRANSPORT

38. ACTIVE TRANSPORT - usually movement of particles from an area of low to high concentration *requires energy!

39. Large Particle Movement • Endocytosis-bringing particles within the cell • Exocytosis- releasing particles (exit)