1. Cell Structure & Function

2. Cell Theory All living things are made of cells
Cells are the basic unit of life
All cells come from pre-existing cells

3. What do all cells have in common?
Genetic information (DNA)
Cytoplasm – fluid-filled region between center and cell membrane

4. What do all cells have in common?
3. Cell membrane (plasma membrane) – surrounds cell
Function: regulates what enters and leaves cell
4. Ribosomes – make proteins using instructions from DNA

6. How big is a cell?
Animation – Cell Size

7. Surface Area to Volume Ratio
Why are cells so small?
Ratio of surface area to volume
Much greater for small cells
Space is important for cells to receive nutrients, oxygen, and to remove waste
Volume increases faster than surface area as cells grow
Greater volume= more metabolic reactions BUT more difficult to transport wastes and nutrients
The smaller the cell, the more efficient it is to transport materials across it

9. Organisms can be: Unicellular Consist of only 1 cell Multicellular
Consist of multiple cells

10. 2 Basic Cell Types
PROKARYOTIC
EUKARYOTIC

11. Prokaryotic Smaller/unicellular Simple No organelles No nucleus
Ex: Bacteria

12. Eukaryotic Larger-multi or unicellular More complex Many organelles
Structures that have a specific function; “mini- organs”
Nucleus – encloses DNA
Control center of the cell

13. Eukaryotic Ex: Plants, animals, fungi, protists
Unicellular eukaryotes = Protists

14. Unicellular Eukaryote
Protists
Why are protists eukaryotes if they are only made up of ONE cell?
Amoeba
Paramecium
Dinoflagellates

15. Prokaryote vs. Eukaryote -What is different between the two types of cells?

16. Prokaryotes Simple internal structure Nucleoid Region (no nucleus)
Flagellum → whip- like tail used for movement

17. Prokaryotes Most primitive organisms
Pili – short projects that help bacteria attach to surfaces
Most primitive organisms

18. Bacteria E. Coli Strepococcus mutans
S. Mutans causes tooth decay. E. coli causes vomiting, diarrhea, abdominal pain.
E. Coli
Strepococcus mutans

19. Bacteria Mycobacterium tuberculosis Staphylococcus aureus
Staph infections (MRSA as well).
Mycobacterium tuberculosis
Staphylococcus aureus

20. Cell Organelles and Functions
Eukaryotic Cells Internal Structure

21. Eukaryotes
Can be split into plant and animal cells

22. Animal Cell

23. Animal Cell

24. Plant cell

26. Nucleus
Function: Control center of the cell
Eukaryotic cells ONLY!!!

27. Nucleus 3 parts: 1.Contains DNA
A. Chromosome – DNA coiled around proteins called histones
Humans contain 46 chromosomes in nucleus of all cells
Exceptions: Red blood cells (no nucleus), sex cells
B. Chromatin – uncoiled DNA; DNA usually found in this form

28. Nucleus
2. Nuclear envelope (nuclear membrane) – membrane w/ pores to allow materials in and out of the nucleus
3. Nucleolus – inside the nucleus; makes ribosomes

30. Cytoplasm Organelles can be found in the cytoplasm
Cytoplasm- portion of the cell outside of the nucleus

31. Endoplasmic Reticulum(ER)
Folded membranes attached to nucleus
Smooth ER →
Not lined with ribosomes
Synthesizes lipids
Detoxifies chemicals (i.e. liver)
Smooth ER also detoxifies drugs. Liver cells have A LOT of smooth ER.

32. Rough ER Ribosomes- made of RNA & protein
Lined with ribosomes
Function: Modifies proteins that are being transported
Ribosomes- made of RNA & protein
- Function: Assemble proteins based on instructions from DNA

33. C4U Difference between Rough and smooth ER
What are ribosomes? Where can they be found?

35. Golgi apparatus (golgi body)
Looks like a flattened stack of pancakes
Functions:
Receives vesicles (sacs) from the ER and finishes, sorts, and ships protein
“Packages protein”
One side = receiving; other side = shipping

37. Lysosomes Lysosome – Function: Contains powerful digestive enzymes
Digests food particles to release nutrients to cell
Fun Fact  enzyme in lysosome destroys skin between fingers/toes during embryo development

38. Lysosomes “Demolition/cleanup crew” Destroys damaged organelles
Ex: neutrophils (WBC) engulf bacteria
Produced by the Golgi
Tay Sachs disease caused by lysosomes that fail to function properly. Components of the cell membranes build up in nerve cells and usually cause death by the age of 4.

39. Peroxisomes Functions:
Breakdown fatty acids, H2O2 (catalase), synthesis of myelin (for nerve cells)
Produced by the ER
Disease: ALD – caused by peroxisome not functioning properly
ALD (adrenoleukodystrophy) caused by build up of fatty acids in nerve cells. Often leads to a vegetative state.

41. Inside the cell
Working as a TEAM

43. Vacuoles Function: Storage “containers” Animals = small and numerous
store various substances
Animals = small and numerous
Plants = one large central vacuole
Stores mostly water
Helps with the structure of a plant cell

44. Central Vacuole
Also functions as a large lysosome- contains enzymes which break down materials
Increases turgor pressure (internal cell pressure)

45. Turgor Pressure Cell shrinks due to water loss
Cell swells due to influx of water

46. Vacuoles
Contractile vacuole → gets rid of excess water; found in some protists
Prevents bursting of cell & dilution

47. Energy Organelles Chloroplast Plants only Some protists and algae
Function:
Site of photosynthesis
Use sun energy to make food energy

48. Energy Organelles All eukaryotes Function:
Mitochondria
All eukaryotes
Function:
Site of cellular respiration
Creates energy for cell (ATP) from food

49. Mitochondria Contain 2 membranes Outer membrane
Inner membrane- folded up inside the organelle

50. Plant cells ONLY! Cell Wall Chloroplasts – used for photosynthesis
Function: Rigid layer to protect and support cell
Keeps cell from bursting
Made of cellulose (carbohydrate)
Chloroplasts – used for photosynthesis
Large central vacuole

52. Plant Cell

53. Cytoskeleton
- network of protein filaments (fibers) that help the cell maintain its shape
Function: Helps with support/internal structure and movement
Like wood and nails of house

54. Cytoskeleton

55. Cytoskeleton
Made up of microfilaments and microtubules

56. Microfilaments Made of solid globular protein called actin
Used for movement and supports shape
Ex: Muscle contractions

57. Intermediate Filaments
Made of fibrous proteins
They reinforce cell shape and anchor organelles
Ex: Holds nucleus in place

58. Microtubules Hollow tubes of protein called tubulin
They often disassemble and reassemble
Helps with movement)
Ex: lysosome may slide along to reach food
Ex: movement of chromosomes when cells divide

59. Movement Both made of microtubules wrapped in membrane
Cilia → short and numerous; beat together
Ex: Cells of human windpipe sweep pollen & mucous containing debris from lungs
Flagella → few; long and whip-like
Ex: sperm cells

61. Centrioles Type of microtubule
Function: Organize DNA during cell division
ONLY IN ANIMAL CELLS

62. PLANT
ANIMAL
BOTH

63. Use these terms to fill in your Venn Diagram
Cell membrane
Golgi body
Mitochondria
Rough & smooth ER
Nucleus
Cytoskeleton
Ribosomes
Central vacuole
Chloroplast
Centrioles
Lysosome
Cell Wall
Small vacuoles