1. The Cell

2. How big is a cell?
Rearrange these items in order from LARGEST to SMALLEST:
Mitochondrion
E coli bacterium
grain of rice
red blood cell
Glucose
Sperm
carbon atom
water molecule
skin cell

3. Cell Size How big is a cell?

4. Biological Levels of Organization
• Atom
• Molecule
• Macromolecule
• Organelle
• Cell
• Tissue
• Organ
• Organ system
• Organism
• Population
• Community
• Ecosystem
• Biome
• Biosphere
Small
BIG!!

5. • Remove wastes (CO2, etc.) • Reproduce
Needs of a Cell
• Get food
• Get oxygen
• Remove wastes (CO2, etc.)
• Reproduce
– Limits to cell size...when too big, split in two
• Maintain homeostasis.

6. Two Basic Cell Types Prokaryote Lacks internal compartments.
No true nucleus.
Most are single-celled (unicellular) organisms.
Examples: bacteria

7. Two basic cell types
Eukaryote
Has several internal structures (organelles).
True nucleus.
Either unicellular or multi-cellular.
• unicellular example: yeast
• multi-cellular examples:
plants and animals

8. Organelles Small, membrane-bound structures in a cell Specialized
Like organs in the human body

9. Organelles Cell Membrane
Separates the interior of the cell from the exterior (outside) environment.
Selectively permeable: Allows certain materials to pass in and out of the cell.
Function: Protects the cell from its surroundings
Found in plants and animal cells

10. ORganelles Cell Wall Surrounds the plasma membrane
Found in plant, bacteria and fungi cells. NOT ANIMAL CELLS
Function: Provides rigid layer, does not allow over-expansion when water enters.
Have students chat in table groups to come up with a group role for these two.

11. ORganelles
Nucleus
Function: Regulates cell function-acts as a control center
Surrounded by a double-layered membrane (nuclear envelope) with large pores that allow materials to pass in and out of the nucleus.
Contains genetic material, chromatin – long tangles of DNA and chromosomes: coils of DNA.

12. ORGANELLES Chromosomes and Chromatin
Structures made of DNA (Nucleic Acid)
FUNCTION: holds the instructions for how to make the cell’s proteins

13. organelles
Nucleolus
Found in the nucleus and responsible for ribosome production
Ribosomes are the sites of protein production.

14. organelles
Cytoplasm
The jelly-like material that surrounds the organelles.
Function:
support

15. Organelles
Ribosome
FUNCTION: synthesize (makes) protein

16. organelles Endoplasmic reticulum
Folded membrane that acts as a network for transportation.
Smooth E.R. contains enzymes for lipid synthesis.
Rough E.R. is studded with ribosomes for protein synthesis.
Function: cell’s delivery system.

17. Organelles
Golgi apparatus (or Golgi body)
A series of flattened sacs where newly made lipids and proteins from the E.R. are repackaged and shipped to the plasma membrane.
Function: packaging & shipping

18. Organelles Vacuoles A sac of fluid surrounded by a membrane
Function: used to store food, fluid, or waste products.
Plants-1 large vacuole
Animals-few small or no vacuole

19. Organelles Lysosomes Contain a digestive enzyme.
Fuse with vacuoles to digest contents.
Function: breakdown food, waste, worn out organelles, viruses and bacteria.
Also known as “suicide sacs” because they can also destroy the whole cell.

20. Organelles Mitochondria Produce the energy for the cell.
Function: powerhouse of the cell.
Has a highly folded inner membrane called cristae

21. Organelles Chloroplasts Found in plant cells and some protists.
Transforms light energy into chemical energy which is stored in food molecules.
Function: photosynthesis
Contain chlorophyll – a green pigment that traps light energy and gives plants their green color.
Part of a group of plant organelles called Plastids

22. Microtubules – hollow filaments of protein.
Organelles
Cytoskeleton
A network of thin, fibrous materials called Microtubules and Microfilaments that act as a scaffold
Function: support the organelles
Microtubules – hollow filaments of protein.
Microfilaments – solid filaments of protein.

23. Organelles
Centrioles
Star-like structures made of microtubules.
play a role in the splitting of the cell into two cells.
Function: cell division
found in animal and fungi cells.

24. organelles
Cilia
Short, numerous, hair-like projections from the plasma membrane.
Move with a coordinated beating action.

25. Organelles
Flagella
Longer, less numerous projections from the plasma membrane.
Move with a whip-like action.

26. when cells don’t work properly
Cystic Fibrosis-(hereditary)
A defective gene makes a protein that doesn’t work to control the movement of salt and water in and out of your body's cells.
Causes thick, sticky mucus to build up in the lungs, digestive tract, and other areas of the body.
It is one of the most common chronic lung diseases in children and young adults.

27. when cells don’t work properly
Tay-Sachs Disease-(hereditary)
Tay-Sachs disease occurs when the body lacks a protein that helps break down a chemical found in nerve tissue. Without this protein, the chemical builds up in cells, especially nerve cells in the brain.

28. when cells don’t work properly
Sickle Cell Anemia-(hereditary)
red blood cells form an abnormal sickle or crescent shape.
Red blood cells carry oxygen to the body and are normally shaped like a disc. The fragile, sickle-shaped cells deliver less oxygen to the body's tissues.