DO NOW

• Hand in your outlines and get with your partner to begin lab.

DO NOW

• What similarities do you see in the following molecules?

THE MOLECULES OF CELLSChapter 3

OBJECTIVES

• To understand what constitutes an organic compound and why carbon is essential to life.

• To identify the 6 functional groups important in the chemistry of life.

• To explain a dehydration synthesis reaction and how it is used to construct polymers.

CARBON

• Lets draw a molecule of carbon!

• What is so special about it?

• Carbon has 4 valence electrons and therefore can form 4 covalent bonds, allowing branching in 4 directions!

• Any molecule containing carbon= ORGANIC COMPOUND

HYDROCARBONS

• Compounds composed of only hydrogen and carbon.

• The structure effects the properties of the molecule

• Hydrocarbons are nonpolar molecules due to their nonpolar C—H bonds.

CARBON

• Carbon Skeleton Types• Unbranched• Branched• Contain double bonds• Rings

ORGANIC COMPOUNDS

• An organic compound has unique properties that depend upon– The size and shape of the molecule – The groups of atoms (functional groups) attached to it

• A functional group affects a biological molecule’s function in a characteristic way• Ex: OH (hydroxyl group) is polar and therefore soluble in water, which makes

compounds it is attached to Hydrophilic. • CH4 (methyl group) is non-polar and can make compounds it is attached to

hydrophobic.

FUNCTIONAL GROUPS

• The functional groups are– Hydroxyl group—consists of a hydrogen bonded to an oxygen– Carbonyl group—a carbon linked by a double bond to an oxygen atom– Carboxyl group—consists of a carbon double-bonded to both an oxygen and

a hydroxyl group– Amino group—composed of a nitrogen bonded to two hydrogen atoms and

the carbon skeleton– Phosphate group—consists of a phosphorus atom bonded to four oxygen

atoms– Methyl group—consists of a carbon atom bonded to 3 hydrogen atoms

REAL WORLD APPLICATIONS

• An example of similar compounds that differ only in functional groups is sex hormones

– Male and female sex hormones differ only in functional groups

– The differences cause varied molecular actions

– The result is distinguishable features of males and females

PRACTICE

• Get with a partner to complete the worksheet on organic compounds and functional groups.

DO NOW

• Identify the functional groups in the following compound and take out your hw worksheet.

OBJECTIVES

• To understand the general structures of the 4 main biological molecules.

• To determine how smaller molecules join to form larger molecules.

MACROMOLECULES

• Lets review. What are the 4 macromolecules our bodies need to survive?• P.C.F. NA

• Proteins• Carbs• Fats (lipids)• Nucleic Acids

THE BUILDING BLOCKS

• Each macromolecule is a type of “polymer” made up of smaller “monomers”. • Carbs- Monosaccharides• Proteins- Amino Acids• Nucleic Acids- Nucleotides• Lipids- Glycerol + Fatty Acids

POGIL ACTIVITY

• Lets take a closer look at some of these molecules!

• Get with your assigned group and complete the “Biological Molecules” activity.

TEST

• Lets go over your last test!

• While we do this, think about the following• Did I do as well or as poorly as I thought I would?• Why did I get questions wrong? – go through each question and pick one of

the following reasons as to why you got it wrong…• 1. I didn’t understand the question• 2. I made a silly error• 3. I did not study this specific material• 4. Something else?

LETS REVIEW

• What does benedicts solution indicate?

• What do you need to do to initiate a reaction for benedicts?

• What does iodine indicate?

• Take out your lab from last week!

OBJECTIVES

• To determine the structural differences of mono, di, and polysaccharides and provide examples of each.

• To determine which types of carbs are present in common foods.

ORGANIC SUBSTANCES LAB

• Today we are going to be doing part B “Testing unknown substances”.

• Each table will need a hot plate with a beaker of water on it, a test tube rack with test tubes, and the indicators.

• Please wear Goggles, gloves, and an apron as safety precautions.

DO NOW

• What 3 elements make up macromolecules?

• What are the monomers of carbohydrates?

• How do these monomers come together to form a polymer?

HOW CAN WE FORM MACROMOLECULES?

Look at the following diagram and hypothesize how these molecules come together.

HYDROLYSIS AND DEHYDRATION SYNTHESIS

HOW DO WE GET THESE MACROMOLECULES?

• Monomers are linked together to form polymers through dehydration synthesis reactions, which remove water

• Polymers are broken apart by hydrolysis, the addition of water

• All biological reactions of this sort are mediated by enzymes, which speed up chemical reactions in cells

A CLOSER LOOK AT CARBOHYDRATES

• Carbohydrates range from small sugar molecules (monomers) to large polysaccharides

– Sugar monomers are monosaccharides, such as glucose and fructose– These can be hooked together to form the polysaccharides

CARBS

• The carbon skeletons of monosaccharides vary in length– Glucose and fructose are six carbons long– Others have three to seven carbon atoms

• Monosaccharides are the main fuels for cellular work– Monosaccharides are also used as raw materials to manufacture other

organic molecules

Glucose(an aldose)

Fructose(a ketose)

DISACCHARIDES

• Two monosaccharides (monomers) can bond to form a disaccharide in a dehydration reaction

– An example is a glucose monomer bonding to a fructose monomer to form sucrose, a common disaccharide

POLYSACCHARIDES

• Polysaccharides are polymers of monosaccharides

– They can function in the cell as a storage molecule or as a structural compound

POLYSACCHARIDES

• Starch is a storage polysaccharide composed of glucose monomers and found in plants

• Glycogen is a storage polysaccharide composed of glucose, which is hydrolyzed by animals when glucose is needed

• Cellulose is a polymer of glucose that forms plant cell walls

• Chitin is a polysaccharide used by insects and crustaceans to build an exoskeleton

PARTNER PRACTICE

• Complete the carbohydrates worksheet with your partner. You may move to a lab table if you wish.

DO NOW

• Please clear your desk for your quiz.

OBJECTIVES

• To understand how to test for lipids using two different methods.

• To identify the structure of lipids.

EMULSION TEST

• Read the intro to your lab after your lab quiz and answer the following questions:

• 1. Why is ethanol used in this lab?

• 2. Explain how emulsion works.

LIPIDS

• Lipids are water insoluble (hydrophobic, or water fearing) compounds that are important in energy storage

– They contain twice as much energy as a polysaccharide

• Fats are lipids made from glycerol and fatty acids

LIPIDS

• Fatty acids link to glycerol by a dehydration reaction

– A fat contains one glycerol linked to three fatty acids

– Fats are often called triglycerides because of their structure

TYPES OF FATS

• Some fatty acids contain double bonds

– This causes kinks or bends in the carbon chain because the maximum number of hydrogen atoms cannot bond to the carbons at the double bond

– These compounds are called unsaturated fats because they have fewer than the maximum number of hydrogens

– Fats with the maximum number of hydrogens are called saturated fats

UNSATURATED FAT

TRANS FATS