1. Cells
Chapter 7

2. What is a Cell? The basic unit of all forms of life
Smallest unit of life

3. How were cells discovered?
Van Leeuwenhoek: 1600’s, invented the microscope
Hooke: 1665, first to see cells and names them cells because they remind him of small rooms
Schleiden: 1838, all plants made of cells
Schwann: 1839, all animals made up of cells
Virchow: 1855, all cells come from preexisting cells

4. The Cell Theory All living things are composed of cells.
Cells are the basic units of structure and function in living things
New cells are produced from existing cells

5. Cell Structure Many shapes and sizes 5 – 50 micrometers in diameter
Smallest cells = bacteria
Large cells = giant amoeba (1000 micrometers)

6. Basic Cell Structures
Cell Membrane = thin, flexible barrier around the cell. Help support and protect the cell and determines what gets in and out of the cell
Cell Wall = strong layer outside of the cell membrane (plant cells). Used for support and protection.

7. Basic Cell Structures
Nucleus: controls the cell and holds the genetic material
Cytoplasm: material inside the cell membrane (gooey) that holds the nucleus and other cell structures

8. 2 Types of Cells
Prokaryotes: no nucleus, small simple, still considered living
- Ex. bacteria
2. Eukaryotes: have a nucleus and organelles (cell organs), can live on their own or make up multicellular organisms (plants, animals)

9. Cell Structures
Chapter 7-2

10. Animal Cell

11. The Nucleus Controls all of the cell processes
Holds the hereditary info (DNA)

12. Parts of the Nucleus: Chromatin: DNA attached to protein
Chromosomes: condensed chromatin, how DNA is passed on to offspring
Nucleolus: dense center of nucleus, makes ribosomes
Nuclear Envelope:
membrane around the nucleus

13. The Cytoskeleton protein filaments that support and move the cell
Microtubules: hollow tubes that move organelles
Cilia and Flagella: outside of the cell, move the cell
Microfilaments: thin fibers that support the cell

14. Ribosomes Make proteins
Turns RNA into protein using instructions from the nucleus
Free = floating in the cytoplasm
Attached = attached to the membranes of organelles

15. Endoplasmic Reticulum (ER)
Assembles components of the cell membrane, modifies proteins
Rough ER = has ribosomes attached, protein modifier
Smooth ER = no attached ribosomes, enzyme collector

16. Golgi Apparatus Stacks of membranes Packages and sends proteins
Attaches carbohydrates and lipids to proteins and then sends them to the rest of the cell to be used

17. Lysosomes Small organelle filled with enzymes
Uses its enzymes to break down lipids, carbohydrates, and proteins so they can be used

18. Mitochondria Releases energy from food
Uses energy from food to make high-energy compounds that the cell can use to power growth, development, and movement

19. Animal Cell

20. Plant Cell

21. Cell Wall Lies outside the cell membrane
Lets water, oxygen, carbon dioxide, and other substances pass
Provides support and protection for the cell
Made up of carbohydrates and proteins (cellulose)

22. Vacuoles Storage containers
Store water, salts, proteins, and carbohydrates
Stores liquid and creates pressure that holds the plant up with its flowers and leaves

23. Chloroplasts Contain the pigment chlorophyll (green)
Catches the energy from the sun to make energy-rich food molecules (photosynthesis)

24. Plant vs. Animal Cells

25. Cell Summary

26. Cells gotta work to live!
What jobs do cells have to do?
make proteins
proteins control every cell function
make energy
for daily life
for growth
make more cells
growth
repair
Renewal
Cells Use Different Organelles to Accomplish the Jobs

27. Proteins do all the work!
cells
DNA
Repeat after me…
Proteins do all the work!
organism

28. Cells functions Building proteins read DNA instructions build proteins
Nucleus
build proteins
Ribosomes
process proteins
Rough ER, Smooth ER
address & transport proteins
Golgi Body

29. Building Proteins Organelles involved nucleus ribosomes
endoplasmic reticulum (ER)
Golgi apparatus
vesicles
The Protein Assembly Line
Golgi apparatus
nucleus
ribosome ER
vesicles

30. Any Questions!!