Welcome to Class! DO NOW (No talking) Today’s Agenda Make sure you have followed classroom procedures Use a dry erase board and marker: Write down as many parts of the microscope as you can remember. List at 5 procedures for using the microscope. DO NOW Review microscope Biochemistry Vocabulary Biochemistry Introduction (molecules and pH) Create a pH scale Homework: (1) Be sure to wear closed toed shoes all week. Labs this week involve lots of chemicals and special tools. (2) Organize your notebooks.

Biochemistry Introduction Basics and Bonding

Lesson Frame We will learn the basics of molecules and bonding and about the pH scale. I will pre-assess my vocabulary knowledge, create vocabulary flashcards, and a pH scale.

Biochemistry Vocabulary What is the Wall of Vocabulary Masters Tournament? How should I make my vocabulary flashcards?

Atoms vs. Molecules Atom = smallest unit of matter - made of protons, neutrons and electrons Example – Oxygen (O) Molecule = more than one atom bonded together Example – Oxygen gas (O2) Compound = more than one type of atom bonded together Example – Water (H2O)

Composition of Life

Types of Bonds Atoms within molecules are held together by one of two major types of bonds: Covalent – a pair of electrons is shared between 2 atoms, each atom donated one electron to the pair Ionic – electrons are given to nonmetals by metals creating ions, held together by opposite electric charges

Covalent Bond – Shared e- Ionic Bond – given/taken of e-

Solutions A solution is a mixture in which one or more substance are uniformly distributed in another substance Solute = the substance dissolved in the solution I.e.: “Solid” Ex: Sugar Solvent = the substance in which the solute is dissolved I.e.: “Liquid” that does the dissolving Water or Coffee

pH The pH scale ranges from 0 to 14 Measures the amount of H+ ions in the solution Solutions ranging from 0 – 7 = acids (acidic) 7 is a neutral pH Solutions ranging from 7 – 14 = bases (basic) PAUSE: Create a pH scale http://www.glencoe.com/sites/common_assets/science/virtual_labs/E22/E22.html?_sm_byp=iVVtHRMjV2PM0QWF

Create a pH scale Using your resources around the room, create a pH scale by placing the items where you think they belong on your scale. Do not glue until I check. Use pencil

pH Scale with examples

Acids and Bases A solution that has a high concentration of H + ions is said to be acidic, giving it a low pH Examples: Lemon juice, vinegar A solution that has a low concentration of H + ions is said to be basic, giving it a high pH Examples: Ammonia, Tums A neutral pH is one in which the ion concentrations are the same Example: Water Note: Low [H+] is the same as having a High [OH-]

Buffer The control of pH in the body is very important. Certain enzymes can only work in a narrow pH range. Buffers: chemical substances that neutralize acidic or basic solutions. (help maintain pH)

Exit Ticket Postcard If you could write a postcard to your parents or your bestfriend describing what you learned today in class, what would you say? Write a brief postcard describing what you learned today.

Water’s Structure The oxygen and hydrogen atoms are held together with covalent bonds Oxygen keeps electrons more, making it partially negative Hydrogens become partially positive Combined this makes water polar

Water’s Structure (cont.) Two water molecules will then attract each other and are held together with fairly weak bonds called hydrogen bonds

Water’s Important Properties (3) Water helps to regulate temperature Has a high specific heat = takes a lot of energy to raise the temperature of water Has a high heat of vaporization = water absorbs a great deal of heat when it evaporates Water is cohesive Water is attracted to itself due to the polarity of the molecule Gives water a high surface tension

Water’s Important Properties (3) Water is an excellent solvent for polar compounds “Like dissolves like” Most molecules in cells are polar Ex: Carbohydrates, Proteins and Nucleic Acids Most of the body’s and cell’s fluids are aqueous solutions where water is the solvent

Other Properties of Water Video: (4:31) The Chemistry of Water Video (Youtube – 4:32): https://www.youtube.com/watch?v=DAilC0sjvy0

Why Carbon is Important Organic - in chemistry, is used to describe a molecule that possesses both carbon and hydrogen Inorganic - a compound that does not contain both carbon and hydrogen Most biological molecules that make up cells are organic

Synthesis of Molecules Because most organic molecules are large and complex, smaller subunits will be used to synthesize longer molecules Individual subunits are called monomers Long chains of monomers are called polymers Water is often produced as a by-product when molecules are synthesized in the body

Dehydration Synthesis Subunits are almost always linked together by a chemical reaction called dehydration synthesis A H+ atom is removed from one subunit while a hydroxyl group OH- is removed from another The H + and OH- will combine to form water

Hydrolysis The reverse reaction, called hydrolysis Used to split a molecule into individual monomers In order for this to happen, water must be used