DID YOU KNOW? Laser-printing organs! http://www.youtube.com/ watch?v=oAs0k2lQa4M Let’s look back… evolution of cells! Spontaneous polymerization of atoms into molecules and biomolecules Beginning of Earth (atoms) 4.5billion First PROKARYOTES were very simple and oxygen was lacking from the atmosphere so they lived in water 4billion 3.8billion Membranes formed from lipids and nucleic acids formed DNA/RNA ENDOSYMBIOTIC THEORY: large prokaryotes engulfed smaller ones, which became organelles inside! EUKARYOTES are formed 3billion 2billion Prokaryotes became photosynthetic, producing oxygen for the atmosphere and using oxygen for efficient energy use 600million Unicellular eukaryotes clumped together to form colonies. Multicellular organisms are formed and highly complex with specialized parts 500million Fish and land-based plants (mosses) evolved 400million First humans are thought to have evolved from the Homo Genus 200,000 NOW Scientists are growing cells, mapping the human genome and making organs from laser printers! Insects and Trees Life is Cellular Who is on top of the food chain? Take a second to think about it while you watch this clip: http://youtu.be/4XBvDx2Lhfs Those tiny, little, one-celled organismS known as bacteria can affect us in many different ways……….. Now, Who do you think is on top of the food chain?! All living things are made of at least one cell. The word “CELL” comes from the Latin word “cella” meaning small room. It was coined by Robert Hooke, who compared cork cells he saw in a microscope to the small rooms monks lived in. What are CELLS? *CELLS are microscopic building blocks that make up all living things. Just like monomers build into polymers, cells build into living organisms *Everything that is alive has at least one cell! This guy has cells. Unicellular organisms! This cute puppy has cells, too! How many cells do humans have? *Depending on the source, that figure varies from 50 to 75 trillion cells!! *That’s 75,000,000,000,000…a whole lot of zeroes! Describe “cells” in your own words. Uni vs. Multi Fill out the T-chart as we go through unicellular vs. multicellular organisms! Some things are UNIcellular. UNICELLULAR means one-celled. UNI = one. (Like uno!) Bacteria are an example of a unicellular organism. Unicellular cells are only made up of 1 cell so that 1 cell has to do it all! Unicellular Humans are MULTIcellular. *MULTICELLULAR means many-celled! *Remember: MULTI = many. *Plants, fungi, and animals are MULTICELLULAR. *Multicellular cells have many specialized parts & that have specific roles that they are in charge of. *These parts and organs are called organelles. What is the difference between a unicellular organism and a multicellular organism? The Cell Theory : 1.All living things are made up of at least one cell! 2. Cells are the basic building blocks of life. 3. All cells come from preexisting cells Exploring the Cell Cells are microscopic… this means we cannot see it with the naked eye. Prokaryotes (bacteria are smaller than eukaryotes!) We can view cells through a compound light microscope! Isn’t there more than one kind of cell? YES! Plants, animals, fungi and protists have different cells than bacteria. There are 2 types of cells: Prokaryotic cells Eukaryotic cells What do prokaryotic cells and eukaryotic cells have in common? Cell membrane Cell wall Cytoplasm Ribosomes **They both have nucleic acids (DNA /RNA)** PRO vs. EU Fill out the T-chart as we go through prokaryotic vs eukaryotic organisms! PROKARYOTIC CELLS ONLY *PROKARYOTES are different from eukaryotes in three ways: 1. Prokaryotes have NO NUCLEUS 2. They have NO membrane-bound ORGANELLES 3. BACTERIA ARE PROKARYOTES. Prokaryotic cells DO NOT contain membrane bound organelles. Prokaryotes *Small and simple *Do NOT have a nucleus *Do not contain membrane bound organelles *Most abundant organisms on earth *Two major groups 1. Archaebacteria (oldest known and live in extreme environments) 2. Eubacteria (most common) *All prokaryotes are unicellular PROKARYOTIC CELLS Prokaryotes do, however, have ribosomes, a cell wall, a cell membrane, and genetic material (nucleic acids). Bacteria (microorganisms) Bacteria is a prokaryotic organism What are 3 characteristics that prokaryotic cells have? Why is bacteria (which is also known as a microorganism) considered a prokaryotic organism? What is 1 cool fact about bacteria that you did not know? PROKARYOTES Salmonella sp. : found in raw chicken and eggs. (recently found in PB) PROKARYOTES Staphylococcus aureus: causes staph infections Staph infections are usually passed when the infected area of one person’s skin touches the skin of another person. They must be kept covered at all times and are EXTREMELY contagious! E. coli on the surface of a pin E.coli is found in feces What are 3 illnesses caused by bacteria? So…where are some places that bacteria can be found? How about ALL OVER YOUR CELL PHONES…ewwww http://youtu.be/4lmwb BzClAc Eukaryotes *Contain a nucleus *Contain membrane bound organelles *Some are single-celled Organisms, most are multicellular *Generally larger than prokaryotes Ex: plants, animals, fungi, protists Eukaryotic cells HAVE membrane bound organelles. Eukaryotes Composed of 4 main parts: • cell membrane - outer boundary of the cell • cytoplasm - jelly-like fluid interior of the cell • nucleus - the "control center" of the cell, contains the cell's DNA (chromosomes) • organelles - "little organs" that carry out cell functions What are 3 characteristics about eukaryotic cells? EUKARYOTES ANIMALS EUKARYOTES EUKARYOTES EUKARYOTES