Structures & Functions The Cell Structures & Functions

What is “Cell Theory”? Schleiden, Schwann and Virchow developed the cell theory in the mid 1800s. All living things are composed of cells. Cells are the basic units of structure and function in living things. All cells come from other living cells.

What is so special about cells? Cells are the smallest units capable of performing life functions. What is so special about cells?

Where do cells come from? All cells come from pre-existing cells through cell division (mitosis and meiosis).

Basic Types of Cells Eukaryotic Prokaryotic

Cells Dividing: Bacteria from a Taxi Cab Prokaryotic Unicellular organisms Bacteria Few internal structures surrounded by membranes Cells Dividing: Bacteria from a Taxi Cab

Eukaryotic Contain organelles surrounded by membranes Most living organisms Plants Animals

“Typical” Animal Cell

Human nerve cells in the medulla oblongata

“Typical” Plant Cell

Cornstalk Cells

Cell Membrane Outer boundary of the cell made of a double lipid layer containing proteins Protects, supports and moves materials in and out of the cell Selectively permeable membrane

Large, oval structure that contains chromosomes “Control Center” of the cell that directs all of cell’s activities Found in the center of the cell “nuc” means center

Chromatin/Chromosomes Contain DNA (genetic material) and proteins “Blueprints” of life (instructions for all of an organism’s characteristics) Found in nucleus

Nucleolus & Nuclear Membrane Nucleolus (Nucleoli) Makes ribosomes Found inside the nucleus Nuclear Membrane Surrounds nucleus Lets things in/out of nucleus (pores) Selectively permeable cell

Cytoplasm Gel-like material that fills the cell Holds the organelles

Endoplasmic Reticulum (E.R.) Network of tubes and membranes that transports materials through the cytoplasm “Transportation System” of the cell Two types: smooth and rough (has ribosomes) Attaches from cell membrane to nuclear membrane

Rough E.R. Smooth E.R.

Ribosomes Small circular granules Make proteins Found in cytoplasm or attached to E.R.

Mitochondria Bean shaped structure that makes energy for cell “Powerhouse” of the cell Found in cytoplasm

Mitochondria Mitochondrion

Vacuoles “Storage Tanks” of the cell Found in cytoplasm Bubble- shaped structures that store food, water & waste Vacuoles “Storage Tanks” of the cell

Vacuole

Golgi Bodies or Golgi Apparatus Stacks of saclike structures that package and move proteins to other parts of the cell “Post Office” of the cell Found in cytoplasm

GOLGI APPARATUS

Lysosome Usually in Animal Cells Contains digestive enzymes that destroy bacteria, old cell parts… Found in cytoplasm

Chloroplast Only in plant cells Contains chlorophyll (green pigment) Perform photosynthesis

Cell Cartoon Practice http://www.indiana.edu/~istdept/R521/student_workbook.pdf

Cell Wall Only in plant cells Rigid covering on the outside of the cell membrane that supports & protects the cell Made of cellulose

Can you name these plant cell parts? B. C.

Can you name these animal cell parts? Cell Membrane Rough E.R. Ribosomes Cytoskeleton or Microfilaments Mitochondria #1 #2 #4 #3