Chapter 2 The Chemistry of Life

Section 1: The Nature of Matter

Objectives What three subatomic particles make up atoms? How are all the isotopes of an element similar? What are the two types of chemical bonds?

The Big Idea Life Depends on chemistry Chemical reactions keep you alive

Atom Basic unit of matter

Democrites

Subatomic particles Protons - Neutrons - Electrons - Positively charged (+) Not charged (neutral) Negatively charged (-) Bind together to form the nucleus Electrons Protons Neutrons Nucleus

Element A pure substance that consists of just one type of atom

6 C Carbon Atomic number An elements atomic number = number of protons

Isotope Atoms of the same element that differ in the number of neutrons they contain

Nonradioactive carbon-12Nonradioactive carbon-13Radioactive carbon-14 6 electrons 6 protons 6 neutrons 6 electrons 6 protons 8 neutrons 6 electrons 6 protons 7 neutrons

6 C Carbon Mass number The Sum of protons and neutrons in the nucleus of an atom is its mass number

The weighted average of the masses of an elements isotope is called its atomic mass

Radioactive isotopes Can be dangerous Can be used practically –Radioactive dating –Treat cancer –Kill bacteria

Compounds A substance formed by the chemical combination of two or more elements in definite proportions Ex) H 2 O, NaCl

Table Salt

Ionic Bonds Formed when one or more electrons are transferred from one atom to another

Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na + ) Chloride ion (Cl - ) Transfer of electron Protons +11 Electrons -11 Charge 0 Protons +17 Electrons -17 Charge 0 Protons +11 Electrons -10 Charge +1 Protons +17 Electrons -18 Charge -1

If an atom loses an electron it becomes positive If an atom gains an electron it becomes negative

Ions Positively and negatively charged atoms

Covalent Bonds Forms when electrons are shared between atoms

Molecule The structure that results when atoms are joined together by a covalent bond Smallest unit of most compounds

Van der Waals Forces A slight attraction that develops between the oppositely charged regions of nearby molecules due to unequal sharing of electrons

Section 2: Properties of Water

Objectives Why are water molecules polar? What are acidic solutions? What are basic solutions?

The Big Idea Much of our planet is covered in water Water is necessary for life to exist If life exists on other planets, there most likely is water present Water has many properties that make life possible

Polarity (-) (+) The oxygen atom has a stronger attraction for electrons

Hydrogen Bonds Because of waters partial charges, they can attract each other and create hydrogen bonds Not as strong as covalent or ionic bonds Waters ability to create multiple hydrogen bonds gives it many special properties

Cohesion Attraction between molecules of the same substance

Adhesion Attraction molecules of different substances

Mixture Material composed of two or more elements or compounds that are physically mixed but not chemically combined Ex.) salt & pepper, earths atmosphere

Solutions Mixture of two or more substances in which the molecules are evenly distributed Ex.) salt water Settles out over time

Solutions Cl - Water Cl - Na + Water Na +

Solute Substance that is dissolved Ex.) salt

Solvent The substance that does the dissolving Ex.) Water

Suspensions Mixture of water and non- dissolved materials Ex.) sugar solution, blood Separate into pieces so small, they never settle out

The pH scale Indicated the concentration of hydrogen ions in a solution

Neutral Acid Base

Acids Any compound that forms H + (hydrogen) ions in solution

Base A compound that produces OH - (hydroxide) ions in solution

Buffers Weak acids or bases that can react with strong acids or bases to prevent sharp, sudden pH changes

Section 3: Carbon Compounds

Objective What are the functions of each group of organic compounds?

Most of the compounds that make up living things contain carbon. In fact, carbon makes up the basic structure, or “backbone,” of these compounds. Each atom of carbon has four electrons in its outer energy level, which makes it possible for each carbon atom to form four bonds with other atoms. As a result, carbon atoms can form long chains. A huge number of different carbon compounds exist. Each compound has a different structure. For example, carbon chains can be straight or branching. Also, other kinds of atoms can be attached to the carbon chain. Section 2-3 Interest Grabber Life’s backbone

MethaneAcetyleneButadieneBenzene Isooctane

Macromolecules “giant molecules” Formed by a process called polymerization

Monomers Smaller units

Polymers Linked up monomers

Carbohydrates Compounds made up of carbon, hydrogen, and oxygen atoms usually in a ratio of 1:2:1 Main source of energy The monomers of starch are sugars

Single sugar molecules are called monosaccharides The large macromolecules formed from monosaccharides are known as polysaccharides

Starch Glucose

Lipids Made mostly from carbon and hydrogen atoms Used to store energy

Lipid Glycerol Fatty Acids

Proteins Macromolecules that contain nitrogen as well as carbon, hydrogen, and oxygen Proteins are polymers of molecules called amino acids

Amino Acids General structureAlanineSerine Carboxyl group

More than 20 different amino acids, can join to any other amino acid The instructions for arranging amino acids into many different proteins are stored in DNA Each protein has a specific role The shape of proteins can be very important

Proteins Amino Acids

Nucleic Acids Macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus Double Helix

Nucleotides Consists of 3 parts: 5-carbon sugar, phosphate group and nitrogen base Nitrogen Base 5-Carbon Sugar Phosphate group

2 kinds of nucleic acids RNA (ribonucleic acids) – contains sugar ribose DNA (deoxyribonucleic acid) – contains sugar deoxyribose

Section 4: Chemical Reactions and Enzymes

Objectives What happens to chemical bonds during chemical reactions? How do energy changes affect whether a chemical reaction will occur? Why are enzymes important to living things?

The Big Idea Living things are made up of chemical compounds Everything that happens to an organism is based on chemical reactions

Chemical Reactions A process that changes or transforms one set of chemicals into another

Reactants Elements or compounds that enter into a reaction

Products Elements or compounds produced by a chemical reaction

Example Reaction: Getting rid of carbon dioxide In the blood In the lungs CO 2 + H 2 0  H 2 CO 3 (carbonic acid) H 2 CO 3  CO 2 + H 2 O Released as you breathe

Energy in reactions Energy-Absorbing Reaction Energy-Releasing Reaction Products Activation energy Activation energy Reactants

Activation Energy The energy that is needed to get a reaction started

Enzymes Some chemical reactions are too slow or have activation energies that are too high to make them practical for living tissue These chemical reactions are made possible by catalysts

Catalyst Substance that speeds up the rate of chemical reactions Work by lowering a reactions activation energy

Enzyme Biological catalysts Speed up reactions in cells Very specific Named for the reaction it catylzes Enzyme names always end in - ase Enzymes can be reused as long as they are not denatured

Reaction pathway without enzyme Activation energy without enzyme Activation energy with enzyme Reaction pathway with enzyme Reactants Products

Substrates The reactants of enzyme catalyzed reactions The active site of the enzyme and the substrate have complementary shapes Fit like a lock and key

Enzyme Action Enzyme – substrate complex

Glucose Substrates ATP Substrates bind to enzyme Substrates are converted into products Enzyme-substrate complex Enzyme (hexokinase) ADP Products Glucose-6- phosphate Products are released Active site

Regulation of Enzyme Activity Enzymes are affected by any variable that affects chemical reactions 1.pH 2.Temperature 3.Concentration of enzyme

M I N I L E S S O N: ( mins) CHEMICAL BASIS OF LIFE CODE:GIVES WATCH Glucose Iinsulin Vaccine EstrogenEnzymes Starch Water Amino acids AntibodiesAntigens Testosterone Catalyst Hormone TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system? AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet

Chemical Substances Glucose - simple sugar M I N I L E S S O N: ( mins) - building blocks of starch GIVES WATCH AGENDA State Standard 1,2 &4 CCSS: Grades 9-10 RST 4, 7 DO NOW: ( 5 mins) Match vocabulary words to their correct description MINI LESSON: ( mins) Brainstorm the word chemicals Discuss the difference between organic and inorganic compounds identify various examples of organic compounds Identify and discuss various life processes ACTIVITY: ( mins) Slideshow SUMMARY ( 10 mins ) HOMEWORK ( 5 mins ) TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system?

Chemical Substances Insulin - hormone that regulates sugar in the blood M I N I L E S S O N: ( mins) - produced by the pancreas AGENDA State Standard 1,2 &4 CCSS: Grades 9-10 RST 4, 7 DO NOW: ( 5 mins) Match vocabulary words to their correct description MINI LESSON: ( mins) Brainstorm the word chemicals Discuss the difference between organic and inorganic compounds identify various examples of organic compounds Identify and discuss various life processes ACTIVITY: ( mins) Slideshow SUMMARY ( 10 mins ) HOMEWORK ( 5 mins ) TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system?

Chemical Substances Vaccine - consists of dead pathogens ( bacteria or viruses) -s-stimulates the body to produce antibodies M I N I L E S S O N: ( mins) AGENDA State Standard 1,2 &4 CCSS: Grades 9-10 RST 4, 7 DO NOW: ( 5 mins) Match vocabulary words to their correct description MINI LESSON: ( mins) Brainstorm the word chemicals Discuss the difference between organic and inorganic compounds identify various examples of organic compounds Identify and discuss various life processes ACTIVITY: ( mins) Slideshow SUMMARY ( 10 mins ) HOMEWORK ( 5 mins ) TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system?

Chemical Substance Estrogen - female reproductive hormone M I N I L E S S O N: ( mins) AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet - produced by the ovaries - helps in the production of eggs TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system?

Chemical Substance STARCH - made up of glucose molecules M I N I L E S S O N: ( mins) AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet - produced by plants TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system?

Chemical Substance Antibodie s - produced by white blood cells M I N I L E S S O N: ( mins) rotect the body against pathogens White blood cells antibodies Pathogens TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system? AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet

Chemical Substance Amino acids- building blocks of protein M I N I L E S S O N: ( mins) Testosterone- male hormones - produced by the testes - helps in the production of sperm TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system? AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet

Chemical Substance M I N I L E S S O N: ( mins) Catalyst - chemical that speeds up chemical reaction. - one example is an enzyme Hormone- chemical messengers that are responsible for cell communication -E-Examples:Insulin,Estrogen,testosterone TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system? AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet

Chemical Substance Enzymes - a special type of protein that breaks down, cuts and speed up chemical reaction. M I N I L E S S O N: ( mins) - most enzymes end with - ase TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system?

DO NOW QUIZ: (5-10 mins) 1.State what is in a vaccine that makes it effective. 2. Explain how a vaccine prevents future infections? Vaccine is made up of dead or weakened virus or bacteria Vaccine will make the body produce antibodies 3. Identify the genetic event that can change a flu virus strain into a different strain. MUTATION TOPIC: Use of Acronyms: GIVES WATCH AIM: How can we explain the importance of chemical substances in the living system? AGENDA DO NOW: Answer sample regents question. MINI LESSON: Identify what each word from the code give swatch represent. Discuss each example of chemical substance ACTIVITY: Slideshow REFLECTION HOMEWORK Homework Sheet