Cell Organelles Unit 2: Cells Ch. 7-2 Use this presentation in conjunction with the Cell Organelle note-taking worksheet. Run through the entire presentation before using it in class so that you know what’s coming next! It helps to print the outline and notes to have with you while presenting so that there are no surprises. –JessB.org

Two cell types Prokaryotes (Prokaryotic Cells) Let’s Review! Two cell types Prokaryotes (Prokaryotic Cells) Eukaryotes (Eukaryotic Cells)

Prokaryotes - Bacteria No Nucleus No Membrane bound organelles.

Eukaryotes Have a nucleus Have membrane bound organelles Nucleus

Two Types of Eukaryotic Cells Animal Cell Plant Cell Both cells function similarly

Cell Organelles Organelle = “little organs” Specialized structures that perform specific jobs in the cell Found only in eukaryotic cells Many are “membrane-bound” (a membrane surrounds the organelle) All the stuff in between the organelles is cytosol Everything in a cell except the nucleus is cytoplasm You may or may not wish to distinguish between cytosol and cytoplasm. The correct use of each term is shown here. Most high school textbooks, however, use the word “cytoplasm” to mean “cytosol.”

Cell Membrane Surrounds the cell and decides what comes in and out Semi-permeable: allows nutrients in and waste products out Made of a phospholipid bilayer Also called Plasma Membrane Emphasize word parts here: phospho= phosphate head; lipid= fatty acid tail bi= 2

Factory Part: Found in: Gates or Doors Plant cells Animal cells Prokaryotic cells

Nucleus Control center of the cell Stores DNA (chromosomes) Surrounded by the nuclear membrane Pores let material in and out Also contains the Nucleolus, which makes ribosomes Cells with more than one nucleus include muscle cells and liver cells, largely because of the massive volume of cytoplasm and number of organelles that need controlling.

Factory Part: Manager’s Office Found in: Plant cells Animal cells

That looks familiar…what is a polypeptide? Ribosome Smallest organelle NOT surrounded by a membrane Makes proteins according to DNA instructions. Two Types: Free ribosomes: float free in cytosol Bound ribosomes: attached to rough ER A polypeptide is a chain of amino acids. In this diagram, you can see the ribosome is making a polypeptide, also known as a protein. That looks familiar…what is a polypeptide?

Factory Part: Found in: Machines Plant cells Animal cells Prokaryotic cells

Endoplasmic Reticulum Transport system for materials in cell Two Types: Rough ER: covered with ribosomes; site of protein synthesis Smooth ER: NO ribosomes; it makes hormones & lipids It’s not necessary that the students can read the labels here; just point out the black dots are ribosomes.

Factory Part: Conveyor Belts Found in: Plant cells Animal cells

Golgi Apparatus Delivery system of the cell Collects, modifies, and packages molecules in the cell Distributes and transports molecules in vesicles AKA Golgi Complex. It is not necessary that the students read the labels, this diagram gives them a general idea of the Golgi’s shape.

Factory Part: Found in: Post office or Mail Room Plant cells Animal cells

Lysosomes Clean-up crew of the cell Contain digestive enzymes that break down macromolecules for the cell to use Removes waste particles Students should recognize the shapes of the Golgi and ER even if they cannot read the captions.

Factory Part: Janitors Found in: Plant cells Animal cells

Mitochondria “Powerhouse” of the cell Site of cellular respiration Converts energy stored in food into energy the cell needs – ATP Explain that this diagram shows the mitochondria cut open to reveal the internal membranes. Sugar + Oxygen Carbon dioxide + Water + ATP ATP = Adenosine triphosphate

Factory Part: Found in: Power Plant / Electrical Room Plant cells Animal cells

Chloroplast Site of photosynthesis Changes sunlight energy into chemical energy (glucose) Contains green pigment, chlorophyll Found only in plant cells and algae Chloroplasts absorb light, which is the catalyst for photosynthesis. Sunlight + Carbon Dioxide + Water Sugar + Oxygen

Factory Part: Solar Powered Energy Panels Found in: Plant cells

Cell Wall Rigid, protective barrier (maintains cell shape) Found in plant and bacterial cells Located outside of the cell membrane Made of cellulose (Carbohydrate fiber) This is an actual microscopic image. Explain that the colors are added digitally to enhance the different parts.

Factory Part: Found in: Factory Gates Plant cells Some Prokaryote cells

Vacuoles Storage tank Holds water, food, enzymes, wastes, etc Large central vacuole usually in plant cells Supports cell shape in plants Many smaller vacuoles in animal cells The image is 2D, so it must have been a light microscope or TEM. If the cell is very tiny, then a TEM was used. Otherwise, a strong light microscope could have captured this image.

Factory Part: Found in: Storage room Plant cells Animal cells (smaller)

Quick Review Which organelle is the control center of the cell? Nucleus Which organelle holds the cell together? Cell membrane Which organelles are not found in animal cells? Cell wall, central vacuole, chloroplasts Which organelle helps plant cells make food? Chloroplasts What does E.R. stand for? Endoplasmic reticulum You may choose to delete the answers from the PowerPoint or change the animation so that they come in after all 5 questions are asked in case you want to quiz students individually at the end.

Cell City Analogy Cell Organelles City Analogies Cell Membrane City border Cell Wall City Wall Cytoplasm Lawns Endoplasmic Reticulum Highway or road system Ribosomes Lumber or brick yard Golgi Bodies Post Office or UPS Chloroplasts Solar Energy Plants Nuclear Membrane City Hall Fence with security guard Mitochondria Energy Plants Nucleus City Hall DNA Original Blueprints or the city RNA Copies of Blueprints Nucleolus Copy Machine Lysosomes Waste Disposal/ Recyclers Vacuole Warehouses, water towers or garbage dumps Protoplasm Air or atmosphere Chromosomes Rolled up blueprints Proteins Lumber or bricks