• Used a “microscope” / magnifying glass to look at cork
• From England
• Discovered what a cell was by looking at a piece of cork

• Dutch inventor who created the microscope that we recognize today
• First person to discover a single celled protozoa
  • Protozoa is like pond scum
• He also looked at blood cells

• All organisms are made of one or more cells
• The cell is the basic unit of all living things
• All cells come from existing cells

• Prokaryotes are molecules surrounded by a membrane and cell wall. Prokaryotic cells lack characteristic Eukaryotic sub cellular membrane enclosed “organelles”, but may contain membrane systems inside a cell wall.

• SAME As bacteria since they lack a nucleus and don’t have membrane bound organelles.
• DIFFERENT in that they have ribosomes that are more like a Eukaryotic cell.

Eukaryotic Cell (2nd Major Kind of Cell)
Cells that have a membrane around their nucleus.

Example – Plant and Animal Cells Eukaryotic

Cells usually are 10 times larger than Prokaryote cells.

The basic Eukaryotic cell contains the following:

1. Plasma membrane around their nucleus
2. Cytoplasm (the semi fluid substance inside the membrane.
3. Has a cytoskeleton – the microfilaments and microtubules that suspend organelles, this gives it shape, and allow for the cells motion.
4. Has membrane enclosed subsellular organelles.

The things or structures (PARTS) inside of a cell that perform the functions necessary for the cell to survive.

• Example: Think about your heart, lungs and liver… They are all organs or organelles inside of your body. The cell has parts like this inside of its cell.

Is the protective layer that covers the cell’s surface.

it acts like the fence around a yard. It is like the skin on your body. It keeps some things out and lets some thing in.

Location:	Found in all cells
Description	Plant - inside cell wall Animal - outer layer; cholesterol Double layer of phospholipids with proteins Selectively permeable
Function	Support Protection Controls movement of materials in/out of cell Barrier between cell and its environment Maintains homeostasis

• Found only in PLANT cells
• Gives support to the cell
• Is a second layer or “fence” like the cell membrane.

Location:	Plant, Fungi, & Bacteria, but not animal cells
Description	Outer layer Rigid & strong Made of cellulose
Function	Support (grow tall) Protection allows H2O, O2, CO2 to diffuse in & out of cell

• An organelle inside of the cell that directs the activity in the cell.
• It holds the DNA (Deoxyribonucleic acid)
• This is the blue print material (directions) for the cell.
• It tells how to reproduce and perform all of the cells jobs.

Location:	All cells except prokaryotes
Description	Large, oval May contain 1 or more nucleoli Holds DNA
Function	Controls cell activities Contains the hereditary material of the cell

nucleolus

• A folded membrane that moves material in the cell
• ER (Endoplasmic Reticulum) is part of the internal delivery system and uses tubes for passageways.
• ER is additionally responsible for moving proteins and other carbohydrates to the Golgi Body.

Location:	All cells except prokaryotes
Description	Network of tubes or membranes Smooth w/o ribosomes Rough with embedded ribosomes Connects to nuclear envelope & cell membra
Function	Carries materials through cell Aids in making proteins

Golgi Body (Apparatus)

• consisting of flat, disk-shaped sacs, tubules, and vesicles
• Stacks of sacs that package and move proteins around in the cell.

Location:	All cells except prokaryotes
Description	Stacks of flattened sacs
Function	Modify proteins made by the cells Package & export proteins

• The organelle that releases energy in the cell. (The powerhouse of the cell)
• Only found in ANIMAL cells.
• Mitochondria produce ATP using energy stored in food molecules.

Location:	All cells except prokaryotes
Description	Peanut shaped  Double membrane Outer membrane smooth Inner membrane folded into cristae
Function	Breaks down sugar (glucose) molecules to release energy Site of aerobic cellular respiration

• Organelle that produces chlorophyll. ( The chemical of photosynthesis) to power the plant cell.
• Chlorophyll traps the energy of sunlight, which is then used by the plant cell to make sugar for energy.
• Only found in PLANT cells.

Location:	Plants and algae
Description	Green, oval  containing chlorophyll (green pigment) Double membrane with inner membrane modified into sacs called thylakoids Stacks of thylakoids called grana & interconnected Gel like innermost substance called stroma
Function	Uses energy from sun to make food (glucose) for the plant Process called photosynthesis Release oxygen

Ribosome:

Organelle that makes protein for the cell.

Location:	All cells
Description	Small bodies free or attached to ER Made of rRNA & protein
Function	Synthesizes proteins

Vesicle / Vacuole

Small sack that moves material in and out of the cell.

Location:	Plant cells have a single, large vacuole Animal cells have small vacuoles
Description	Fluid-filled sacs Largest organelle in plant cells
Function	Store food, water, metabolic & toxic wastes Store large amounts of food or sugars in plants

• Organelle that eats worn out cell parts.
• It contains digestive enzymes.
• Lysosomes are round membrane surrounded structures that can be found anywhere in the cytoplasm.
• Sometimes they are called suicide bags because they encase the worn out part that is to be digested.

Location:	Animal as well as plant cells
Description	Small and round with a single membrane
Function	Breaks down larger food molecules into smaller molecules Digests old cell parts

• The gel-like material inside of the cell membrane.
• Keeps organelles in place

Location:	All cells
Description	Clear, thick, jellylike material (cytosol) Organelles found inside cell membrane Contains the cytoskeleton fibers
Function	Supports and protects cell organelles

Cytoskeleton:

Centrioles

Cilia

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