1. CELLS  Two main types of cells are ______ and _______.
Prokaryotic; eukaryotic
Bacterial; animal
Nerves; muscles
Plant; animal

2. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
The boundary structure that physically defines a cell is the
Cell wall
Selective permeability
Plasma membrane
Protein coat
The correct answer is C.
Many students believe that all cells, including animal cells, have a cell wall.
Answer A is incorrect, because only plants and some bacteria have a cell wall.
Answer B is incorrect because this is not a structure, but a function.
Answer D is incorrect because no cells have a protein coat. Only viruses have these.
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3. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
Where is the secreted protein insulin synthesized?
In the Golgi apparatus
On the rough ER
On ribosomes in the cytoplasm
In the nucleus
The correct answer is A. Many students miss this important distinction because it is only mentioned at the beginning of the chapter, after which only plant and animal cells are discussed. It’s worth stressing that most of life on earth is prokaryotic.
Answer B is incorrect because there are eukaryotic cells besides animal cells (e.g., plant and fungi).
Answer C is incorrect because these are just two examples of eukaryotic cells in animals.
Answer D is incorrect because these are just two examples of eukaryotic cells.
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4. Cell Is the Basic Unit of Life
Cell theory: An organism can be one celled or multicellular
Multicellular organisms have billions of cells
Humans have over 200 types of cells
Hooke first described cells in 1665
Schleiden (1838) recognized plant cells
Schwann (1839) reported animal cells
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5. cells are too small to be viewed by the naked eye, one way to increase resolution is to increase magnification, such as by using a microscope

6. 6

7. Cell types two major types: Prokaryotic: bacteria and archae
lacks a nucleus
Without a system of internal membranes
Eukaryotic: algae, fungi, plants, animals
has a nucleus
has internal membrane-bound compartments

9. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
Prokaryotes
Little internal organization
Much smaller than eukaryotes
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10. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
Eukaryotes
DNA contained in nucleus
Membrane‑enclosed
organelles
Internal compartments
for special functions
Figure 5.2
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11. Different eukaryotic cells
Protist, fungi, plants= cell wall beyond the plasma membrane
Protist, plants= chloroplasts
Plants= central vacuole
Animals= centrioles

12. Cell Structure
Cellular structure is organized:

13. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
The Plasma Membrane
Defines the boundary of the cell
Consists of a bilayer of lipids with proteins for communication with external environment
Selective permeability
and act as markers= blood types
Fluid mosaic model
Mobility of components of the membrane
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14. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e3

15. Nucleus: The Administrative Office
command and control center of the cell
stores hereditary information: DNA
Surrounded by a double-membrane nuclear envelope
Nuclear pores are gateways for molecules
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16. Nucleolus dark-staining region of the nucleus
contains the genes that code for the rRNA (ribosomal RNA) that makes up the ribosomes
the subunits leave the nucleus via the nuclear pores and the final ribosome is assembled in the cytoplasm

17. Mitochondrion: Power Plant
Double‑membrane organelle
Inner membrane folded into cristae
Harnesses energy from chemical breakdown
Cellular respiration
Produce ATP
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18. Chloroplast: Photosynthesis
Double‑membrane organelle
Contains grana, made of thylakoids
Converts CO2 and H2O into sugars using light
Chlorophyll enables photosynthesis
Figure 5.10
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19. The Endoplasmic Reticulum: The Factory Floor
Interconnected tubes and flattened sacs
Rough ER
Ribosomes
Makes membrane
and secreted proteins
Smooth ER
Makes membrane vesicles
Figure 5.4
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20. Golgi: Shipping Department
Stacked, flattened membrane sacs
Processes new proteins and lipids
Adds specific chemical groups
Targets them to their destinations
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21. Vesicles: Movement in the Cell
Membrane‑enclosed sacs
Transport vesicles
Moving substances from one location to another
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22. Lysosomes: Clean-up Crew
Small spherical organelles
Contain enzymes to break down macromolecules
Release simple sugars, amino acids, and fats to be recycled
To clear cell of damaged organelles
As a source of food
To destroy invading bacteria
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23. Peroxisomes: Detoxy centers
Derivate from membranes in the cell
The functions are:
detoxify harmful byproducts of metabolism
convert fats to carbohydrates in plants seeds for growth

24. The Central Vacuole: Storage
A specialized structure in plants and fungi
Breaks down substances
Stores chemicals
for later use
Fills with water to
provide rigidity
Figure 5.8
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25. Cytoskeleton: Gives the cell its shape Provides internal support
microtubule
intermediate
filament
microfilament
Gives the cell its shape
Provides internal support
Is responsible for movement 27

26. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
Movement
Used as tracks for vesicle movement or the whole cell
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27. © 2009 W.W. Norton & Company, Inc. DISCOVER BIOLOGY 4/e
Cilia and Flagella
Cilia beat in unison like oars
Flagella beat like whips
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28. Centrioles complex structures In animal cells and protists Functions:
anchor locomotory structures
assemble microtubules near the nuclear envelope for the cell division

29. Cell Wall found in function in: Plants Fungi protists Protection
maintaining cell shape
preventing excessive water loss/uptake

30. Extracellular matrix (ECM)
Outside the plasma membrane
in animal cells
mixture of proteins: Collagen and elastin for protective layer
ECM coordinates cells functioning as tissues

31. Evolution of Organelles
Eukaryotes most likely evolved from prokaryotes
Larger prokaryotes ingested smaller prokaryotes
Free-living mitochondria and chloroplasts were captured
Formed an endosymbiotic relationship with the host cell
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32. Extra credit…. Make flash cards with all the following terms
Cell
Chloroplast
Chromosome
Cilium
Ribosome
Rough ER
Smooth ER
Vacuole
Vesicle
Lysosome
Mitochondrion
Nuclear envelope
Nucleolus
Nucleus
Organelle
Plasma membrane
Prokaryote
peroxysome
Cytoplasm
Cytoskeleton
Eukaryote
Flagellum
Fluid mosaic model
Golgi apparatus
Extra cellular matrix

33. Review Question 1: Cell theory includes the principle that
cells are the smallest living things
all cells are surrounded by cell walls
all organisms are made up of many cells
Nothing smaller than an organelle is considered alive.
2: The plasma membrane is:
carbohydrate layer that to protect
double lipid layer with proteins inserted in it
thin sheet of structural proteins that lines the inside of some body cavities
composed of blood plasma that has solidified into a protective barrier.
3: Organisms that have cells with cytoplasm and no organelles are called ______________, and organisms whose cells have organelles and a nucleus are called ______________
cellulose, nuclear
flagellated, streptococcal
eukaryotes, prokaryotes
prokaryotes, eukaryotes

34. 4: Within the nucleus of a cell you can find ________
5: The endomembrane system within a cell includes
cytoskeleton and ribosomes.
prokaryotes and eukaryotes
endoplasmic reticulum and Golgi
mitochondria and the chloroplasts.
6: Which of the following statements is true?
All cells have a cell wall for protection and structure.
Eukaryotic cells in plants and fungi, and all prokaryotes, have a cell wall.
There is a second membrane composed of structural carbohydrates surrounding all cells.
Prokaryotes and all cells of eukaryotic animals have a cell wall.