350 likes | 489 Views
In This Lesson: Organic Molecules and Early Earth (Lesson 7 of 9). Today is Friday (!), September 27 th , 2013. Pre-Class: What kind of snake is this? Get a strip of paper from the turn-in box. Don’t write on it!
E N D
In This Lesson: Organic Molecules and Early Earth (Lesson 7 of 9) Today is Friday (!),September 27th, 2013 • Pre-Class: • What kind of snake is this? • Get a strip of paper from the turn-in box. Don’t write on it! • Please also get a SMALL paper towel for your partner/table if you do not already have one. http://scienceblogs.com/zooillogix/.jpg
Spitting Cobra http://www.kingsnai.co.za/attachments/Image/spitting_20cobra.jpg
Spitting Cobra (Naja genus) http://1.bp.blogspot.com/_7eeP4sigHj0/Ro-ZLtjJ5FI/AAAAAAAAA2A/rO5s1ObCQsc/s400/spit.png http://www.bio.davidson.edu/people/midorcas/animalphysiology/websites/2005/Koike/fangcomp.jpg
Today’s Agenda • Find out what snake venom is. • This will lead us into our next topic. • New note format recommendation. • BioScale addition • Challenge Questions • Arts and crafts? • Learn organic molecules in overview form. • How life began on Earth… • Where is this in my book? • Academic: P. 44 and following… • Honors: P. 34 and following…
Organizing Your Notes • For this lesson, there are some “big idea” bits of info, followed by details. • It might be a good idea to take a front/back blank page and label it “Organic Molecules.” • Front: Big Idea Notes • Back: Graphic Organizer
Snake Venom • What could such a powerful substance as snake venom (or lizard/bee venom or primate/bird poison) be composed of? http://www.newinfo2day.com/wp-content/uploads/2009/03/slow-loris.jpg http://www.japanprobe.com/2007/01/slow-loris.jpg
Protein • Snake venom is actually, as scientists commonly put it, a “cocktail” of proteins. • In other words, a whole bunch mixed together. • Brings new meaning to the phrase “pick your poison.”
Okay, so what’s protein? • Well? • Scientists classify protein as one of four kinds of organic molecules. • How big are we talking, here? • http://learn.genetics.utah.edu/content/begin/cells/scale/ • Scale of the Universe • BioScale!
But first… • Some challenge questions… • Grab yo’ whiteboards.
Organic Molecules • Remember when we said that the elements are the substances that make up EVERYTHING in the known universe? • Well, organic molecules (sometimes called macromolecules) are the types of molecules that make up EVERYTHING that’s alive. • In fact, they also make up some stuff that isn’t alive.
Organic MoleculesConcept Map • For now, leave a lot of room around this concept map as we will repeatedly return to it throughout the lessons. • On this page, you’ll start your concept map, and take down the key facts I’ll be giving on the back of your concept map sheet.
Key Notes (Slide 1 of 2) • Organic molecules mainly have elements from the first three rows of the Periodic Table. • Carbon is always included. • Remember what we said a few lessons ago – carbon’s ability to form long chains and big molecules helps it support life. • Can be classified into four main groups, each as important as the other.
Key Notes (Slide 2 of 2) • Each of these has a basic unit (called amonomer). • Each also has a complex unit that is made of groups of monomers (called a polymer). • You will have to know the names of the building blocks, the bigger units, roughly what they’re made of, and what they do.
But for now… • Let’s start by getting the concept of monomer/polymer down, shall we? • Think of polymers like chains, and monomers like individual links in those chains. Monomer Polymer http://blogs.dallasobserver.com/cityofate/Zinc-Chain.jpg
Monomers & PolymersArts & Crafts • Find the strip of paper you picked up at the beginning of class. On this, once we begin, write your name and the term “Monomer” on one side. • Divide the masking tape strip at your lab tables into small sections and use it to link your strips into chains, leaving one link OPEN. • Then, link to other groups’ chains!
Looking at somereal examples… • Let’s take a look at the four kinds of organic molecules and we’ll identify each one’s monomer and polymer.
Carbohydrates • Composed of carbon, hydrogen, and oxygen. • Monomer: Monosaccharide (simple sugar) • Polymer: Disaccharide (two simple sugars put together) or polysaccharide (many sugars put together) • Fun Fact: A disaccharide is an example of a two-monomer chain known as a dimer.
Examples of Carbohydrates • Monosaccharides: Glucose, fructose. • Disaccharides: Sucrose, maltose. • Polysaccharides: Starch, cellulose, chitin, glycogen. • Important in: Plant structure, animal energy, insect exoskeletons. Chitin exoskeleton http://www.backyardnature.net/pix/exoskel1.jpg
Lipids • Lipids are fats, phospholipids, steroids, hormones, pigments, and waxes (non-polar!). • Monomer: Well…about that… • For now let’s just remember this: • Fat is composed of 3 fatty acid chains and a glycerol molecule. This is called a triglyceride, but it is not a true monomer. • Polymer:No true polymer, but we’ll say fats, phospholipids, pigments, waxes (as above). • Important in: Cell membranes, energy, hormones.
A Little More About Lipids • Some examples include: • Saturated Fats (solid at room temp.) • Unsaturated Fats (liquid (oil) at room temp.) • Cholesterol • Testosterone, estrogen, progesterone, and other excesses in this room. Chef Boyardee Chicken Alfredo with Pasta http://blog.foodfacts.com/wp-content/uploads/2009/06/food-label-with-ingredients2.jpg
Proteins • Monomer: Amino acid. • Polymer: Polypeptide. • Important in: Enzymes, cell structures, viruses, making more proteins, lots of other stuff. • Examples: Phenylalanine, tryptophan (amino acids), catalase. http://www.dreamviews.com/community/showthread.php?t=52863
Nucleic Acids • Monomer: Nucleotide (A, T, G, C) • Polymer: Nucleic Acid • Important in: Reproduction, heredity, protein creation. • Examples: DNA, RNA. http://puesoccurrences.files.wordpress.com/2009/07/dna_500.jpg
Big Picture? • These organic molecules come together to accomplish complex tasks for the body/cell. • A good example is how the human body handles blood sugar after a meal: • Your stomach enzymes (protein) break down carbohydrates into simple sugars. • First, blood glucose (monosaccharide) levels rise. • The hormone insulin (lipid) is released by the pancreas to store the excess sugar in the liver as glycogen (polysaccharide). • The stored glycogen can then be used later when another hormone called glucagon (lipid) is released.
Wait one second… • So we’ve got all these organic molecules and they’re the basis for life, right? • Where’d they come from? • Guesses?
Old Earth • With a partner, take 1.14 minutes and try to think of how organic molecules may have formed on Earth. • Hint: “They just formed” doesn’t count. • We will discuss your thoughts when the 1.14 minutes are up. We need actual “first this, then this” sorts of stuff for the board.
Oparin-Haldane Model • The Early Earth: • Earth was a “primordial soup” made of organic molecules that were formed when volcanoes erupted or lightning struck. • At least, these were the thoughts of A.I. Oparin and J.B.S. Haldane back in the ‘20s.
The Miller-Urey Experiment • In 1953, Stanley Miller and Harold Urey decided to try and prove the Oparin-Haldane model. Harold Urey Stanley Miller http://www.amnh.org/education/resources/rfl/web/essaybooks/earth/images/urey_01.jpg
Cooking with Urey and Miller • Ingredients: Methane, nitrogen gas, ammonia, water and water vapor, hydrogen gas. • Directions: Preheat oven to “Lightning.” • Makes enough servings of organic molecules for life.
What They “Cooked” • Sure enough, Miller and Urey found amino acids (protein monomers), fatty acids (lipid monomers), and some hydrocarbons after their experiment. • But was it accurate?
The Lerman Model (1986) • We now know that Miller and Urey used some gases that may not actually have been present when organic molecules were forming. • Louis Lerman formed the Bubble Model in response. • Volcanic eruptions in the ocean formed molecules in bubbles, which rose to the surface, went into the atmosphere, and reacted to form more complex organic molecules. • How old is life on Earth as estimated? • 4.5 billion years. Give or take…
But then there’s theBig Question: • Are organic molecules alive? • Are you eating living things when you eat lipids, proteins, and carbohydrates? • What is the most basic and smallest living unit? • This to be answered in greater detail later in the year.
Closure • Exclusion Brainstorming! • With your partner, figure out which of the items on the list DOES NOT belong there/fit in. • Remember from Sesame Street? • Write it on your whiteboard.
Exclusion Brainstorming • Example 1: • Carbohydrates, water, lipids, nucleic acids • Answer: Water – not an organic molecule. • Example 2: • Glucose, chitin, starch, triglyceride • Answer: Triglyceride – not a carbohydrate. • Example 3: • Amino acid, fatty acid, protein, polypeptide • Answer: Fatty acid – not a protein.
Exclusion Brainstorming • Example 4: • Steroid, maltose, pigment, testosterone • Answer: Maltose – not a lipid. • Example 5: • Monosaccharide, nucleotide, amino acid, polypeptide • Answer: Polypeptide – not a monomer. • Example 6: • Triglyceride, fatty acid, oil, steroid • TRICK QUESTION – they’re all lipids.
Your First Assignment… • …is to put together everything we’ve covered so far. • You’re going to make a mini-poster (on a standard sheet of paper). • On it you will put information on a certain compound that we will see later in this semester. • Things to include: • Element Composition • Protons, Neutrons, Electrons of each element • Type of bond (if ionic, covalent, or hydrogen) • Electron configuration • Polarity (we’re getting there)