The Cell Theory SOL BIO 2a

The Cell Theory  The development and refinement of magnifying lenses and light microscopes made the observation and description of microscopic organisms and living cells possible.

The Cell Theory  Many scientists contributed to the cell theory

Microscope/Leeuwenhoek image: Animation from: ___________________________________ a Dutch microscope maker was the first to see LIVING ORGANISMS in pond water. Anton van Leeuwenhoek

Microscope image: Cork image: Hooke image: ______________________ used a microscope to examine a thin slice of cork and saw “little boxes” He called them “CELLS” because they looked like the small rooms that monks lived in called Cells Robert Hooke

Plant image: Schleiden image: German botanist __________________________ concluded that ALL PLANTS are made of cells Matthias Schleiden

Schwann image: Animals image: German zoologist _________________________ concluded that ALL ANIMALS ARE MADE OF CELLS Theodor Schwann

Virchow: Mitosis: German medical doctor _____________________ saw dividing cells in the microscope and reasoned that cells come from other cells Rudolph Virchow

CELL THEORY 1. All living things are ________________________. 2. Cells are the basic unit of ____________ & _____________ in an organism. (cell = basic unit of _____________) 3. Cells come from the reproduction of ____________ cells Cell image: MADE OF CELLS other life STRUCTURE FUNCTION

The Cell Theory  Continued advances in microscopy allowed observation of cell organelles and structure.

The Discovery of Cells before nucleus true nucleus

The Discovery of Cells Two basic types of cells Prokaryotes Prokaryotes - cells with no nucleus or membrane bound organelles Eukaryotes Eukaryotes – cells with a nucleus and membrane bound organelles

Eukaryotic Cell Contain 3 basic parts:  Cell Membrane  Nucleus  Cytoplasm with organelles

Two Main Types of Eukaryotic Cells Plant Cell Animal Cell

1. Cell (Plasma) Membrane Outside of cell Inside of cell (cytoplasm) Cell membrane Proteins Protein channel Lipid bilayer Carbohydrate chains  “doorway of the cell”  The membrane that surrounds the cell  Controls what enters or leaves the cell

Cell (Plasma) Membrane

Control center of the cell Acts as the brain of the cell and regulates and controls all activities of the cell 2. Nucleus

Nucleus

a. Nuclear Envelope (Membrane)  Double membrane that encloses the nucleus  Contains pores for materials to enter & leave nucleus Nuclear pores

Nuclear Membrane

b. DNA The genetic material

DNA

c. Nucleolus  Makes ribosomes that make proteins

Nucleolus

Jelly-like substance enclosed by cell membrane 3. Cytoplasm cytoplasm Contains organelles to carry out specific jobs Found in ALL cells

Organelles

a.Endoplasmic Reticulum - ER Two kinds of ER ---SMOOTH & ROUGH  Transportation system of the cell  Acts like a highway and transports materials throughout the cell.

Endoplasmic Reticulum

b. Ribosomes  “Protein factories” for cell  Join amino acids to make proteins  Process called protein synthesis 

b. Ribosomes Can be attached to Rough ER OR Be free (unattached) in the cytoplasm

Ribosomes (dots)

c. Mitochondrion (plural = mitochondria)  “Powerhouse” of the cell  Generate cellular energy (ATP)  More active cells like muscle cells have MORE mitochondria

Mitochondria

d.Golgi Bodies  Stacks of flattened sacs  The packaging and shipping center of the cell

Golgi Bodies Look like a stack of pancakes Modify, sort, & package molecules from ER for storage OR transport out of cell

Golgi Bodies

e. Vacuoles  Storage tanks of the cell  Used to store waste, food, and water  Plant cells have a large Central Vacuole

Vacuoles

f. Lysosomes  Cleanup crews for the cell  Contain digestive enzymes to break down food, bacteria, and worn out cell parts for cells

Lysosome Digestion Lysosomes digest the food & get rid of wastes

Lysosome

g. Centrioles  Found only in animal cells and active only during cell division  Made of bundle of microtubules

Centriole

Nonliving layer Found in plants, fungi, & bacteria Made of cellulose in plants Made of peptidoglycan in bacteria Made of chitin in Fungi Cell wall h. Cell Wall

 Supports and protects cell  Found outside of the cell membrane

i. Chloroplasts  Found only in producers (organisms containing chlorophyll)  Use energy from sunlight to make own food (glucose)  Energy from sun stored in the Chemical Bonds of Sugars

 The cytoskeleton is a network of protein filaments that helps the cell maintain its shape.  It is also involved in movement. j. cytoskeleton

Cytoskeleton

Differences between plant and animal cells 1. Chloroplasts (plant) 2. Cell Wall (plant) 3. Centrioles (animal) 4. Number and size of vacuoles

Structural Differences Among Cell Types Some

YOU ARE GOING TO DRAW THE FOLLOWING VEN DIAGRAM AND FILL IN THE ANSWERS USING THE WORD BANK PROVIDED

PROKARYOTIC BOTH EUKARYOTIC Nucleus DNA Bacteria Cytoplasm Ribosomes Complex Basic Oldest Small Organelles Large Cell Membrane