6. What makes something living,…

7. Does it have to…
consume oxygen??

8. Does it have to…
be able to move??

9. Does it have to…
be able to think??

10. Does it have to…
grow??

11. Does it have to…
consume food??

12. Does it have to…
have a heart??

13. Does it have to…
reproduce??

14. Does it have to…
be able to die??

15. Characteristics of Life (Hint: There are six total!)
Hmmm…?????
Use these questions and work with your neighbor to compile a list of the
Characteristics of Life
(Hint: There are six total!)

16. 1. Contain Cells
All living things are composed of cells that contain hereditary information (DNA)
In multicellular organisms, cells are specialized for the job that they perform
Cells are the smallest unit of life…so each cell contains the characteristics of life
Nerve Cell
Skin Cell

17. 2. Organization All living things are highly organized.
Click here for
how it works!
All living things are highly organized.
Cell structures carry out particular functions. **Structure equals function!**
Multicellular Organisms: cells are grouped by their function
Cells Tissues Organs Organ systems

18. 3. Energy Use All living things use energy in order to:
Maintain their organization
Grow
Reproduce
Metabolism: chemical process of breaking down materials for energy

19. 4. Maintain Internal Conditions
All living things, even single cells, work to maintain a steady internal environment
Homeostasis: process of maintaining these conditions
Water level in cells
Temperature
Click to see how!

20. 5. Growth and Development
All living things grow as a result of cell division and cell enlargement.
Unicellular (single-celled organisms): Simply an increase in size
Multicellular (many-celled organisms): Develop from one cell into many through cell division (differentiation and different functions)

21. 6. Reproduction
Reproduction (transmitting hereditary information to offspring) is not essential to the survival of an individual organism-it is essential for the continuation of the species.
Two types:
Sexual: cells from two different parents unite to form a new cell
Asexual: new cell formed from
a single cell

22. Scientific Method Observe Ask a Question
Collect Data (background information)
Form a Hypothesis
Experiment
Draw Conclusion
Communicate

23. Variables
Independent Variable- manipulated, the variable that is changed
Dependent Variable- responding, the variable that changes in response to the independent variable

27. Microscope and Measurement
Compound Light Microscope
Magnification:
Increase of the image’s apparent size
Resolution:
The power to show details clearly

28. Parts of Microscope Eyepiece/Ocular Lens Revolving Nosepiece
Objective lenses
Arm
Stage/Stage Clips
Diaphragm/Condenser
Course Adjustment
Lamp
Fine Adjustment
Base

29. High=40X; Low=10X; Scanning=4X
Changes objective lenses
Directs light into microscope
Focuses the light
Amount of light entering the microscope
Look through; lens inside is 10X
Brings objective into slow focus
Carry and support (2 items)
Supports the slide; positions the slide
Brings object into rapid focus

30. So How Do We Use It?? Click on the scientist to see
Now let’s do the lab!

32. Working Space on a Light Microscope
Depth of Field: Area between lens and stage
Field of View: Area seen through the microscope
Calculated by the equation:
Total Mag A X Diameter A = Diameter B
Total Mag B

33. Practice Problems Calculate… Total magnification at: -High Power
-Low Power
-Scanning

34. Ocular x Objective
High = 10x40 = 400
Low = 10x10 = 100
Scanning = 10x4 = 40

35. Practice Problems Calculate…..
If a cell measures 20 um at 100X, what is the length of the cell at 200X?

36. 100 X 20 um = 200
10 um

37. Practice Problems Calculate…
If the field diameter at scanning power measures 5 um, what is the field diameter at low and high power?

38. Low X 5 um = 2 um 100
High X 5 um = 1 um
200

39. Electron Microscope
A beam of electrons produces an enlarged image of the specimen.
Types:
TEM: Transmission Electron Microscope
SEM: Scanning Electron Microscope

40. TEM Can view the internal structure of an organism
Magnifies up to 200,000 times

41. Images under TEM
Lung
Spinach Chloroplast

42. Rat Nerve
Mouse Kidney

43. Sperm and Egg

44. Under an SEM
Pollen
Lung

45. SEM
View the surface of an object
Magnifies up to 100,000 times

46. Under an SEM
Leaf Vein
Staple through paper

47. Under an SEM
Toilet paper
Hypodermic needle

48. Mascara brush with flakes of skin and bacteria
Under an SEM
Mascara brush with flakes of skin and bacteria

49. Under an SEM
Sperm and Egg

50. Comparisons TEM SEM Disadvantages of an electron miscroscope:
Very expensive
Cannot be used to view to a living specimen
Can be large in size