Unit 6: Cell Biology

Unit 6: Cell Biology

Chapter 3.3: Cell Membranes

Chapter 3: CellsSection 3: Cell Membrane

Chapter 3: CellsSection 2: Cell Organelles

Agenda for TodayDo Now!

Quick Review on OrganellesProtein Production

QUIZ!Cell Membrane

Chapter 3: CellsSection 3: Cell Membranes

Good Posters and Presentations!

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Chapter 3: CellsSection 3: Cell Membrane

Do Now!Carolyn and Nouman are giving a presentation about cell organelles. To help the

students understand the function of organelles, they describe the cell by using the analogy that the cell is a factory.

Using the picture below, which part should Carolyn and Nouman describe as the generator (or powerplant) that powers the factory, and why?

Possible answers:• Organelle 1: this structure controls all activities of the cell. • Organelle 2: this structure packages and delivers proteins and lipids. • Organelle 3: this is where cellular respiration occurs. • Organelle 4: this is where photosynthesis occurs.


• Cytoskeleton • “cyto” = “cell”• Supports organelles and gives the

cell structure.• 3 different components:

microtubules, intermediate filaments, & microfilaments.

• Found in Animals and Plants• Found only in Eukaryotes



The Cytoskeleton


• Protein Production

• A number of organelles work together to make and deliver proteins.

• Nucleus -> Ribosome -> Rough ER -> Golgi Body -> Vesicle -> final destination.

• We will use an analogy to describe this process, so be patient.


• Nucleus • “nucleus” = “kernel” (just like “karyon”)

• Stores and protects genetic material (DNA)

• Surrounded by a double membrane with many pores, called the nuclear envelope.

• Nucleolus is the site of ribosome assembly.



• Ribosome• “ribo” comes from RNA (ribonucleic

acid). “soma” = “body”

• Has 2 major parts, a large and a

small subunit.

• In-between the subunits is RNA

• Links amino acids together to form

proteins.



3-D View of Ribosome


• Endoplasmic Reticulum

• “endo” = “inside”; “plasma” = “fluid”; “reticulum” = “net”

• 2 major sections: Rough and Smooth ER

• Rough ER is the site of protein synthesis

• Smooth ER is the site of lipid synthesis (fat, hormones, etc.)

• ER is an extension of the nuclear envelope



Endoplasmic Reticulum


• Golgi Apparatus

• Named after Camillo Golgi, the Italian scientist who first identified it.

• Shaped like a stack of long flattened sacks.

• Packages and ships out/in proteins and other macromolecules.

• Creates vesicles and lysosomes.



Golgi Apparatus (bloop bloop)

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2

3 4

5 5 5 5 5

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• Lysosome • “lyse” = “to break apart”; “soma” = “body”

• Digests worn-out organelles and other cell parts.

• Breaks down viruses, bacteria, and other foreign bodies.

• Full of digestive enzymes and acids.



Lysosome Production


• Mitochondria • “mito” = “thread”; “chondros” = “granule”

• Site of cellular respiration

• The “powerhouse of the cell”

• Breaks down pyruvate(glucose) and makes ATP (cell energy).



Endoplasmic Reticulum


• Chloroplast • “chloros” = “green; “plastis” = “one who forms”

• Site of photosynthesis.

• Converts light energy into chemical energy (glucose).



• Centriole • “kentros” = “center”; “ole” = “little”.

• Help organize microtubles.• Serves as an anchor for spindle

fibers (during mitosis).• Helps form cilia and flagella.• Always occur in pairs, called a

“centrosome”



• Vacuole • “Vacuus” = “empty” ; “-ole” = “small”

• Membrane bound• Stores water, food, and other

important molecules• Found in Animals and Plants


• Vacuole • Found both in Animals and Plants• Smaller in Animals, only used for

storage.• Larger in plants, also used to

maintain turgor pressure and plant structure



• Cell Membrane

• “membrane” = “skin”• Found in all cells (eu, pro, animal,

plant)• Double layer of phospholipids• Hydrophobic between layers,

hydrophilic on outside.• Fluid (everything is in motion)• Semi-permeable• Has many proteins embedded in it.



• Cell Wall • Found only in Plants (Eukaryotes)• Made of cellulose• Provides structure for the plant

body.• Cell wall in prokaryotes in not the

same thing. (made of different stuff)



Journey in to a Cell

http://www.youtube.com/watch?v=1IqsE8CVTms

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Unit 6: Cell Biology