To know prokaryotic and eukaryotic cell structures and their functions How does the cell work as a system responsible for maintaining life? Components of the Cell System Prokaryotes vs. Eukaryotes Cell Membrane Nucleus Cytoplasm Mitochondria Chloroplast Cell Wall
Components of the Cell System Structures and their Functions
Two Basic Types of Cells form a great diversity
Prokaryotes vs. Eukaryotes Nucleoid Region where DNA is stored within a prokaryotic cell
Prokaryotic Cells - a simple but effective compartment Eubacteria and Archaea Cell membrane, cytoplasm, ribosomes, and DNA
Eukaryotic Cells - A compartment full of compartments Animals, plants, fungi, and protists Contain a nucleus and many organelles
1. Cell Membrane Outside boundary of cell Double (“bi”) layer of phospholipid molecules Proteins embedded within; have different functions Protects cell and regulates what enters and exits
2. Cell Wall Plants, some fungi, some bacteria, some protists have this Outside of membrane Provides structure Made of carbohydrates (mainly cellulose, which we know as fiber)
3. Nucleus Holds DNA and controls the cells activities. Pores in the nuclear membrane control flow of materials in and out.
Transmission EM of Nucleus.
3.5 Nucleolus Region within the nucleus where ribosomes are formed Ribosomes?… so ALSO where proteins are also formed!
4. Cytoplasm Present in all cells Jelly-like mixture of water, proteins, salt and carbohydrates. Organelles are embedded in cytoplasm Can be used interchangeably with “hyaloplasm”
The Organelles Smaller, specialized compartments within a cell
5. Mitochondria Where energy stored in food is converted for use in the cell Number of mitochondria in a cell depends on the purpose of the cell Muscle cells Skin cells
6. Chloroplasts Chlorophyll - green pigment that allows for photosynthesis Flattened sacs within “Thylakoids”, where photosynthesis occurs
7. Ribosomes: Not compartments! No membrane; they are composed of two subunits Proteins that make proteins The most abundant of all cell parts
8. Endoplasmic Reticulum Like a highway where molecules move from one part of the cell to another Two types: rough and smooth
8a. Rough Endoplasmic Reticulum Studded with ribosomes! Processes proteins to export from the cell
8b. Smooth Endoplasmic Reticulum No ribosomes! Makes lipids (fats and steroids) Detoxification in liver cells
9. Golgi Bodies/Apparatus System of flattened sacs called cisternae Works with the RER to modify, package and release proteins Spawns vesicles to transport materials to the cell membrane
10. Vacuoles In plant cells: large and used for water + nutrient storage In animal cells: small and numerous and contain a variety of substances
11. Lysosomes Contain chemicals for digesting waste, toxins, or useless organelles Formed from Golgi Common in animal and fungus cells
How do we know all this?
Cell Theory The microscope opened a world of discovery of life never seen before. By 1839, scientists Matthias Schleiden, Theodor Schwann and Rudolf Virchow concluded the following as the…. Cell Theory 1. All living things are made of cells. 2. Cells are the basic unit of structure and function in living things. 3. All cells come from other cells.