Do Now

• What is an atom?

• Why do we have a periodic table?

• What information can we find in a periodic table?

Chapter 6

Biochemistry

Objectives

• To define an atom.

• To determine the make-up of an atom.

• To list different elements that can be found on Earth.

• To explain what type of information can be gathered from the periodic table.

Brain-Based Learning

Proton

ElectronNeutron

Name __________________

Atoms

• Building blocks of matter

• Contain 3 parts– Protons: positively charged, contain mass– Neutrons: no charge, contain mass– Electrons: negatively charged, insignificant

mass

+

-

Atoms make up Elements

• a pure substance that can’t be broken down into other substances by physical or chemical means.

• Made up of only 1 type of atom

• Contain a unique name and symbol.

Periodic Table of Elements

• Periods: horizontal rows

• Groups: vertical columns– elements in the same

group have similar chemical and physical properties.

**Organized based on the # of protons in the nucleus of an atom.**

Periodic Table Information

• Atomic number- tells us the # of protons (and electrons)

• Symbol- unique for each element.

• Atomic Mass- # of protons and neutrons

C6

12.02

Practice Problems

N7

9.01

4

Ne20

C12.02

Complete the missing information and include the number of protons,

neutrons, and electrons.

Neutron Partners…

• List the number of protons, neutrons, and electrons for the following…– Mg– Ca– Fe– Cl

Drawing an atom…

• Things to remember!– Proton # = Electron #– Protons and Neutrons are in the nucleus and

add up to the atomic mass.– Electrons are arranged in energy levels

• 1st energy level holds 2 electrons• 2nd energy level holds 8• 3rd energy level holds 8• Etc.

Lets Draw Oxygen!

• What is the atomic number of oxygen?

Do Now

• Answer the following based on the picture to the right…– Name of Element– # of Protons– # of Neutrons– # of Electrons

K19

39.10

Objectives

• Draw an atom.

• Define isotopes.

• Identify different types of common compounds.

• Compare and contrast the two types of bonds.

Get with your Electron Partner!

1. Draw atoms for the following elements.• Neon• Boron• Lithium

What is wrong with this picture? Carbon

-atomic symbol “C”

-atomic # 6

-atomic mass 12.02

Isotopes

• Isotopes contain the same # of protons as the element, but a different number of neutrons. – Ex: Carbon-14

• Contains 6 protons (still carbon)• Also contains 8 neutrons, instead of 6

**What else will be different other than the number of protons and neutrons?**

Radioactive Isotopes

• What is an isotope again?

• Changing the # of neutrons changes the stability of the atom, causes decay in the nucleus or causes it to break apart.– Ex: Carbon-14 is used in carbon-dating. We

can tell how old something is by how much carbon is left.

What happens if there are different number of ______ than a normal

atom?

• Protons and Neutrons?

• More protons than electrons?

• More electrons than protons?

“Happy” Atoms

• Atoms need to have the right number of electrons around them (happy)

• Ions- charged atom or groups of atoms

• Ions can lose or gain electrons to be neutral

Na- Cl+

How many electrons does each of the following want to be “happy”.

• Oxygen

• Carbon

• Hydrogen

• Nitrogen

Neutron Partners!

• List the number of protons, electrons, and neutrons in each ion – O-– Na+– N3-

• Are any of these atoms happy?

Do Now

• Identify the element and then state if it is a normal atom, an isotope, or an ion.

Objectives

• Identify compounds.

• Determine what information can be gotten from a chemical formula.

• Compare and contrast ionic bonding vs. covalent bonding.

• Explain what “Vanderwalls interactions” are.

Compounds

• A pure substance formed when 2 or more elements combine.– Always formed using a specific ratio

• Ex: 2 molecules of Hydrogen + 1 molecule of Oxygen will give us water (H2O)

– Chemically and physically different from the elements that make them up.

– Must be broken down CHEMICALLY, not physically

Chemical Formulas

• The number before the formula states how many molecules

• Ex. 4 H2O = 4 water molecules

• The subscript number states how many of that type of atom

• Ex. H2O = 2 hydrogen atoms

Let’s try some examples (neutron partners)

For the following examples list the total number of atoms for each element and how many of each molecule.

1. C6H12O6

2. 3CH4

3. 5CO2

4. 3O3

5. 4HCl

How do compounds stay together?

• Bonds!– 2 most common types

1. Covalent- atoms share electrons

2. Ionic- atoms gain or lose electrons to bond

Covalent Bonding

Molecule: compound held together by covalent

bonds.• Carbon (C) – form 4 bonds (another 4 e)• Hydrogen (H) – form one bond (1 e)• Nitrogen (N) – form 3 bonds (3 e)• Oxygen (O) – form 2 bonds (2 e)

• H2O

H HO

Ionic Bonding

Ionic Bond• Some atoms tend to donate or accept

electrons more easily than other atoms.– Ex. Metals (D) and Non Metals (A)

Review!

• How many protons, neutrons, and electrons are in O2-?

• An acid releases ____ ions in solution and a base releases ____ ions in solution.

• Using the formula 3C6H12O6, how many atoms of oxygen are present?

Quiz on the info up till now!

Do Now

• What are the 2 main types of bonds?

• What happens with electrons in each type of bond?

• What is a compound?

Objectives

• Define “Van Der Waals” Interactions.

• Explain what a chemical reaction is.

• Identify reactants and products in a reaction.

• Balance an equation.

Van Der Waals Interactions

When molecules come close together, the attractive forces between slightly positive and negative regions pull on the molecules and hold them together.

The strength of the attraction depends on the size of the molecule, its shape, and its ability to attract electrons.

6.2 Chemical Reactions

• A chemical reaction -atoms or groups of atoms are reorganized into different substances.

• Chemical Reactions:– Production of heat or light,– Formation of a gas, liquid, or solid

Do Now

• What happens during a chemical reaction?

• What are the components of a chemical reaction.

• Write an example of a chemical reaction we have worked with in one of our labs.

Objectives

• To identify reactants and products in a chemical reaction.

• To be able to balance a chemical equation.

• To compare and contrast exothermic vs. endothermic reactions.

Parts of a Reaction

Reaction- Molecules breaking or coming together

Reactants- What goes in the reaction

Products- What comes out of the reaction

Ex: Na+ + Cl- = NaCl

Think – Pair - Share

Glucose and oxygen react to form carbon dioxide and water.

Identify: Products Reactants Is this a chemical equation? Why?

+ ATP

(energy)

Balancing Equations

• The law of conservation of mass states matter cannot be created or destroyed

• The number and types of atoms must be the SAME on both sides of the equations

Ex. ___ H2 + ___O2 ___H2O

H= ____ H= ____

O= ____ O= ____

Electron partners!• Balance the following equations:

• 1. ___ H2 + ___ O2 ---> ___ H2O

• 2. ___ Zn + ___ HCl ---> ___ ZnCl2 + ___ H2

• 3. ___ SiO2 + ___ HF ---> ___ SiF4 + ___ H2O

• 4. ___ K + ___ Br2 ---> ___ KBr

• 5. ___ Al + ___ FeO ---> ___ Al2O3 + ___ Fe

Energy in Reactions

• The activation energy - minimum amount of energy needed for reactants to turn into products

Types of Reactions

• Exothermic- released heat energy. The energy of the product is lower than the

energy of the reactants.

Types of Reactions

• Endothermic - absorbed heat energy.– The energy of the products is higher than the

energy of the reactants.

Think – Pair - Share

• Determine whether or not the following are Exothermic or Endothermic reactions:

• (Neutron Partner)• 1. Combustion reactions of fuels • 2. melting ice cubes • 3. Nuclear Bomb • 4. a candle flame • 5. cooking an egg

Review

• What were the reactants in your liver lab?

• What were the products?

• What type of reaction was it? (endothermic or exothermic)

• Give an example of an endothermic reaction (not the example I gave)

Do Now

• Label the parts of the reaction:

Objectives

• To explain how an enzyme works.

• To determine the difference between a solute and a solvent.

• To list the properties of water.

• To compare heterogeneous vs. homogeneous mixtures.

What you should know about enzymes!

-Specialized proteins that act as “catalyst” (speeds up a reaction)

- Usually end in “ase”

-Not consumed in the reaction

What do they do?

How do they work?

• A substrate fits in the active site of an enzyme. • This forms an enzyme substrate complex.

• They then break or form bonds.

Maltose (substrate)

Maltase (Enzyme)

HOH

HOH

Active Site

Buffers

• What happens to enzymes in a strong pH? (think about our lab!)

• Buffers are mixtures that can react with acids or bases to keep the pH within a particular range. (Remember homeostasis? We want to keep our body fluids at a pH of 6.5-7.5)

6.3 Solutions

• Solution = Mixture of a solute dissolved in a solvent (remember the Kool-Aid!)

• How do things dissolve?– Covalent

• Polar Covalent Bond: Slight Positive and negative charges

• Ex. H2O

• Non-polar: Do not dissolve in water• Ex. Lipids and Fats

Hydrogen Bonds

• A hydrogen bond is a weak interaction involving a hydrogen atom and a fluorine, oxygen, or nitrogen atom.

• It is a strong type of Van Der Waals force.

• Allows water to have special abilities!!

Cohesion

• Cohesion- water molecules are attracted to each other and hydrogen bond with each other, forming surface tension. – Causes water to form droplets and puddles.– Allows insects to “walk on water”

Adhesion

• Water molecules can also form hydrogen bonds on other surfaces by “adhering” to it.– Ex: “Capillary Action”- allows water to travel

up the stem of a plant.

Mixtures

Heterogeneous Homogeneous

What is the difference?

Mixtures

• Homogeneous- has a uniform composition throughout (solutions are homogeneous).

• Heterogeneous- components remain distinct.

Lets Practice!

• Determine whether the following substances are heterogeneous or homogenous:– Chicken noodle soup– Lemonade– Pudding– Fruit Salad– Cole Slaw

Chemistry in Biology

Do Now

Objectives

• List the 4 macromolecules of life.

• Identify the 3 different types of carbohydrates.

• Explain the importance of carbs in the body.

• Explain why low-carb diets can be harmful.

Review

• What is the purpose of an enzyme?

• What are the components of a solution? Give an example.

• What are the 2 properties of water we talked about?

• What are the 2 types of mixtures? Give an example of each.

6.4 Macromolecules of Life

• Organic Chemistry - The element carbon is a component of almost all biological molecules. (Inorganic= no carbon)

Let’s Review

• Carbon has _____ electrons in its outermost energy level.

• One carbon atom can form _____ covalent bonds with other atoms.

Molecules

• Macromolecules -– large molecules formed by joining smaller

organic molecules together.

• Polymers - – molecules made from repeating units of

identical (or nearly identical) compounds linked together by covalent bonds.

Carbohydrates

• Monosaccharide- ranging from three to seven (simple sugar)

• Disaccharide - Two monosaccharides joined together

• Polysaccharide- many monosaccharides joined together

Carbohydrates

• Ratio of carbon : hydrogen : oxygen of 1:2:1

• (CH2O)n

Identify which molecules are carbohydrates…

• 1) C6H12O6

• 2) CH3

• 3) C4H2O2

• 4) C24H36O24

Classify the following as mono, di, or poly – saccaride

• 1. C6H12O6

• 2.

• 3. C12H24O12

• 4.

• Get with your proton partner and join another pair of proton partners! Read the article and answer the questions. Whatever you do not finish will be homework.

Article & Questions

Do Now

• Take out your carbohydrate article!

• What are carbs used for?

• Give an example of a simple carb and a complex carb.

Objectives

• To explain how the body uses fats and proteins.

• To compare and contrast saturated vs. unsaturated fats.

• To understand the two types of cholesterol.

Lipids

• Made mostly of C and H

• Triglyceride – Fat – solid at room temperature– Oil – Liquid at room temperature

Saturated vs. Unsaturated

• Saturated Fats -– Only Single bonds between the

carbons– Solid at room temperature

(typically)

• Unsaturated Fats -– Double bonds between the carbons– Liquid at room temperature

(typically)

Click me

Types of Lipids

Saturated fats Unsaturated fats

Structural differences

all single bonds (one shared pair of electrons)

some double bonds (2 shared pairs of electrons)

Phase of matter solid fats liquid fats

source come from animals come from vegetables

health Less healthy More healthy

Purpose energy storage and insulation

So… people have a problem with….

• Hydrogenated Oils

• Trans fats

• What are they?

• Why do they have a problem?

Cholesterol

HDL LDL

name High density

lipoproteinslow density lipo

proteins

function

transport cholesterol from the body to the liver for breakdown and disposal

transport cholesterol from the liver to the body

Health good cholesterol bad cholesterol

Purpose strengthens cell membranes

Proteins

• Made of small carbon compounds called amino acids

Central Carbon

Atoms that make up Amino Acids: carbon, nitrogen, oxygen, hydrogen, and

sometimes sulfur.

Amino acids are connected together through a PEPTIDE BOND.

Proteins in the Body

• structural - – hair, collagen, muscle etc

• enzymes – – speed up chemical reactions

Nucleic Acids

• complex macromolecules that store and transmit genetic information.

• Nucleic acids are made of smaller repeating subunits called nucleotides

• composed of carbon, nitrogen, oxygen, phosphorus, and hydrogen atoms.

Think – Pair – ShareLet’s Try These

Think – Pair - Share

• Try THESE!