http://koning.ecsu.ctstateu.edu/cell/cell.html
4A: Students will compare and contrast prokaryotic and eukaryotic cells
Robert Hooke (1665) Used a compound microscope to look at thin slices of cork (oak tree bark dead plant cells) Saw empty spaces that looked like rectangular rooms, so he called them cells Matthias Schleidan (1838) First to recognize that all plants (and plant parts) are made of cells
Theodor Schwann (1839) First to recognize all animals (and animal parts) are made of cells When he learned of Schleidan s findings, Schwann published the statement that ALL LIVING THINGS are made of cells Rudolf Virchow (1855) Proposed all living cells come from cells that already exist Until this, most people believed living things could come from non-living matter (spontaneous generation)
All living things are composed of cells. Cells are the basic units (smallest working units) of structure and function of all living things All cells come from preexisting cells through cell division (mitosis).
Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell
A cell is the smallest unit that is capable of performing life functions Lowest level of LIVING organization
Surface Area to Volume Ratio Surface Area = the area covered by the cell membrane Volume = the space taken up on the inside The higher the ratio, the more efficiently substances move through the cell (like bringing nutrients in and moving wastes out) Movement over long distances is slow and hard i.e. = smaller cells move materials faster and more efficiently
Prokaryotic Eukaryotic
Simplest type of cell No membrane-bound organelles One-celled organisms (unicellular); bacteria Bacteria have a single circular chromosome floating in the center of the cell http://library.thinkquest.org/c004535/prokaryotic_cells.html
Surrounded by cell membrane and cell wall Contains ribosomes floating in the cytoplasm to make proteins http://library.thinkquest.org/c004535/prokaryotic_cells.html
Contain organelles surrounded by membranes Most living organisms (protists, fungi, plants, and animals) Some are unicellular, but most are multicellular Most complex type of cell Plant Animal http://library.thinkquest.org/c004535/eukaryotic_cells.html
http://waynesword.palomar.edu/images/plant3.gif
Organelles
Found in everything BUT animal cells! Made of cellulose (chains of glucose) biomolecule? Supports & protects cells
Outside of cell Cell membrane Proteins Composed of a double layer of phospholipids and proteins Also has some carbohydrates (for signaling) Inside of cell (cytoplasm) Protein channel Lipid bilayer Surrounds ALL cells Keeps the insides & outside of the cell separate http://library.thinkquest.org/12413/structures.html Controls movement in and out of the cell (semi-permeable)
Gel-like mixture where the organelles are found (it is in ALL cells) Cushions and protects cell organelles
Surrounds nucleus of eukaryotic cells Openings (pores) allow material to enter and leave nucleus
Directs cell activities in eukaryotic cells ( control center ) Contains genetic material (DNA)
Contain instructions for traits & characteristics Found In nucleus of eukaryotic cells. Freely floating in the cytoplasm of prokaryotic cells Made of DNA (biomolecule?)
Powerhouse of the cell Found in ALL eukaryotic cells Produces energy (ATP) for the cell through cellular respiration by breaking down lipids & carbohydrates http://library.thinkquest.org/12413/structures.html More active cells (ex: muscle cells) have more mitochondria
Power plant of the cell Burns glucose to release energy (ATP) Stores energy as ATP 27
Mitochondria takes the energy from food and stores it in ATP (in the bond between the 2 nd and 3 rd phosphate) The last phosphate group on ATP is broken off to release energy This creates ADP 28
Rough = covered in ribosomes Transports proteins to the Golgi Body.
Has no surface ribosomes and is attached to the end of the rough ER Makes steroids and ions, regulates calcium (muscle cells), & destroys toxins (liver) Sends steroids, ions, and other materials to the Golgi Body to be USED in the cell
Makes protein Each cell contains thousands. Found in all cell types Found on rough ER & also floating throughout the cytoplasm. http://library.thinkquest.org/12413/structures.html
Found in eukaryotic cells Modifies, sorts, & packages molecules from ER for storage OR transport out of the cell http://library.thinkquest.org/12413/structures.html Makes vesicles (packages) to distribute materials to other parts of the cell
Digests unwanted materials and transports them to the cell membrane for removal. Contains digestive enzymes to break down old cell parts Cell breaks down if lysosome explodes ( suicide sac )
Sac containing water that helps maintain the shape of the cell. Stores water, food/nutrients and wastes http://library.thinkquest.org/12413/structures.html
Plant cells have a LARGE central vacuole Needed to regulate pressure Allows the plant to remain rigid (stiff) Without enough water, the plant will wilt (droop) Vacuole http://library.thinkquest.org/12413/structures.html
Found ONLY in plant cells Produces a green pigment called chlorophyll Chloroplasts inside the cells Site of photosynthesis, which uses the energy from sunlight to produce food (sugar) for the cell along with oxygen
Cilia: tiny hair-like structures that line certain cells and provide locomotion Flagella: a long appendage that whips around to provide locomotion
Homeostasis Cell Membrane Cytoplasm Nucleus Lysosome Vacuole Energy Conversion Mitochondria Chloroplast Transport Cell Membrane Endoplasmic Reticulum Golgi Body Formation of new molecules Ribosomes Endoplasmic Reticulum Golgi Body
Animal Cells No cell wall Usually round shape Nucleus towards center Many smaller vacuoles No chloroplasts Plant cells Cell wall Usually rectangular Nucleus near cell wall Large central vacuole Chloroplasts
ALL cells (prokaryote AND eukaryote) have DR.CC cell membrane, cytoplasm, ribosomes, & DNA Prokaryotes are simpler, unicellular, and have NO membrane-bound organelles Bacteria are prokaryotes Eukaryotes are usually multi-cellular (not always), more complex, and have membrane-bound organelles Animals, Plants, Fungi, and Protists are all eukaryotes
Is this a plant cell or animal cell? How can you tell? 41
Contains organelles; a large vacuole, a cell wall and chloroplasts! Cell Wall Vacuole Chloroplast 42
Is this a Prokaryotic or Eukaryotic cell? How can you tell? 43
Contains organelles; a central nucleus, and no cell wall or chloroplasts! 44