Chapter 2 Biochemistry

Chapter 2Biochemistry The Chemistry of Life

pH • Measure of acidity (acid) or alkalinity (basic) • Scale • 0-14 • Acid– b/w 1-6.9 • Ex: stomach acid, urine, lemon juice • Base– b/w 7.1-14 • “alkaline” refers to a base • Ex: intestinal fluid, blood • Neutral - 7 • Look at pH scale pg.44

Dissociation • The process by which compounds break apart when they are “dissolved” in water

CHEMICAL SUBSTANCES THAT NEUTRALIZE SMALL AMOUNTS OF EITHER ACIDS OR BASES Buffers

Buffers Cont- • Needed to maintain a pH of 7 (neutral) • What characteristic of life would maintaining this balance be? _________________ • ***Basic or acidic solutions denature proteins (changes their shape) -- make it where they can’t work****

OCCURS WHEN AN ACID IS COMBINED TO THE SAME AMOUNT OF A BASE • RESULTS IN THE PRODUCTION OF SALT + WATER Neutralization ********************************************

Atoms and Their Interactions

Elements Substances that cannot be broken down into simpler substances Found on the periodic table

Elements • 25 are essential to living organisms • C, H, O, N • 90% of human mass • Remember “CHNOPS”

the smallest particles of an element that has the characterisitics of that element atom

Living organisms • Made of atoms– found inside cells • Protons • Electrons • Neutrons • Put 2 or more atoms together you get elements • 109 elements total • Ex: O2, O3 • 2 or more elements together you get a compound • Ex: H2O, C6H12O6 • ++++++++++++++++++++++++++++++++++++++++++++++++

QSR #4 • 1. Give the symbols for the following elements: • Carbon____ • Hydrogen____ • Sulfur____ • Nitrogen____ • Phosphorus____ • 2. What is the chemical formula for water?____ Carbon dioxide?______ oxygen?_______ Carbon monoxide?______ glucose?_______

All of the chemical reactions that occur within an organism are referred to as Metabolism

Chemical equations • Reactants • Products • Subscripts • Ex: Photosynthesis and respiration equations • Write in your notes and memorize!!!

solution Solvent – present in the greatest amount, and dissolves other substances Solute – dissolves in the solvent Ex: Kool-aid? Ex: atmosphere?

Solutions cont- • THE AMOUNT OF SOLUTE DISSOLVED IN A SOLVENT CONCENTRATION (The higher the solute the higher the concentration) Ex: urine, salt water, orange juice

The opposite of very concentrated – higher solvent concentration diluted

A SOLUTION IN WHICH NO MORE SOLUTES CAN DISSOLVE Saturated Solution +++++++++++++++++++++++++++++

Carbon Compounds • Organic Molecules– molecules that contain mostly Carbon (C) and Hydrogen (H) • 3 Structures of Carbon: • Straight chains • Branched chains • Rings

Branched Chain

Carbon Ring C C C C C C

QSR #4 • 1. Draw a simplified view of a carbon ring. • 2. All compounds are either organic or inorganic. Organic means they contain primarily ___ atoms. • 3. Carbon needs ___ electrons to be stable. • 4. Draw C4H10 as a straight chain and a branched chain and C4H8 as a ring.

Biochemistry • Review: Most common elements in living things are? • C, H, O, & N = 90% of your body mass

Compounds • Macromolecules • Large molecules • Proteins, lipids, carbohydrates, & nucleic acids • Made of subunits called monomers • Ex: Starch is a polymer of what monomer?

QSR #10 1. Vinegar has a pH of 3 which means its an ________ while detergent has a pH of 11 making it a strong __________. 2. Which is the stronger base…11 or 14? ____ 3. Unbalanced pH levels can be harmful to cells, thus _________ in your blood help to maintain a balanced pH. 4. Other than balancing pH levels, what’s one more example of homeostasis?

Biochemistry • Review: Most common elements in living things are? • C, H, O, & N = 90% of your body mass

Building Blocks of Cells 4 Main classes of organic compounds: ORGANIC = CONTAINS CARBON (C) • Carbohydrates • Lipids (fats) • Proteins • Nucleic Acids

Carbs • Made of C,H,O • Include: • Fruits • Veggies • starches

Carbohydrates (also called polysaccharides) 2 JOBS: • 1. provide the body with SHORT TERM energy • Like sugars and starches • 2. Provide structural support in cell walls • Ex: Cellulose – we can’t digest (don’t have enzymes for it)

Carbohydrates 3 types: • 1. Monosaccharides – simple sugars • Found in sugars that come from plants ex: fruit • 1 sugar • Ex: Glucose & fructose – natural sugars found in fruits • EASIEST TO BREAK DOWN FOR ENERGY – but it doesn’t last long at all • “sugar high”

2. Dissacharides – (2 monosaccharides) • 2 sugars – still easy to break down • Provides energy for a little longer • Ex: Sucrose/table sugar – candy, sweet tea • Ex: Lactose – milk sugar – milk, yogurt

3. Polysaccharides – “Complex carbs” • **these are your STARCHES • Many sugars (made of more than one sugar) • HARDEST TO BREAK DOWN – thus it provides energy the longest • Ex: Starch– long chain of sugars • food storage by plants (roots) • Ex: potatoes and rice

Glucose -- simple sugar Fructose – also a simple sugar

Glucose + Fructose = Sucrose

QSR #11 1. Monosaccharides are made of only ___ sugar and are found in _________ and veggies…not _________ sugar. 2. Carbs consist of 3 elements: ___, ____, ____ 3. The main function of carbs is to provide _________ for our cells, with ______________ providing us with the most energy. 4. Sucrose, or “_______ sugar”, is made of 2 monosaccharides (________ and fructose), thus sucrose and ________ are disaccharides.

Lipids • Do not dissolve in water • nonpolar • 2 types • Saturated – solid at room temp • Ex: meats and cheeses • Unsaturated – liquid at room temp • Ex: olive oil • Includes fats, phospholipids, waxes, and oils

Calories • Calories • 1g of fat = 9 calories • 1g of carbs = 4 calories

Types of lipids A. Phospholipids – provide support for cell membranes B. Cholesterol – also found in cell membranes

Lipids • Monomers are fatty acids: • Long chains of C-H bonds with a glycerol end • Fats/oils– • Plant fats: olive oil and peanut oil • Animal fats: butter and meat • Used for • Energy storage • Insulation • Protective covering

SATURATED SATURATED UNSATURATED

Proteins • Made of subunits called amino acids (which are used to build cells) • 20 different amino acids– your body can make 12, so where do the others come from? • Made of C,H,O,N and sometimes S • Ex: Hair and horns are made mostly of protein • What are some foods high in protein?

Proteins • Amino acids are held together by Peptide Bonds • Thus AA’s often form long chains called Polypeptides • Proteins are often large molecules consisting of hundreds of AA’s

Macromolecules and Monomers • Last slide

A protein that changes the rate of a chemical reaction Enzyme

Enzymes • Catalyst that Speed up the digestion of food and other chemical reactions • Act like a lock and key mechanism • Substrate: specific reactants that an enzyme acts on • Ex: Amylase is an enzyme (found in saliva) that recognizes the substrate Starch – thus initiating the break down of starch

Enzymes • Factors that change the shape of enzymes (i.e. proteins) – affecting their function to control chemical reactions in your body: • 1. High temperatures • 2. Unbalanced pH levels

Chapter 2 Biochemistry