chapter 3 study guide

In what ratio are hydrogen & oxygen atoms in carbohydrates?
In what 3 forms do carbohydrates exist?
Monosaccharides, disaccharides, polysaccharides
What are the monomers of carbohydrates called? What is their common name? Give the ratio of carbons, hydrogens, & oxygens.
Monosaccharides-simple sugars, 1:2:1
Name the 3 MOST common monosaccharides.
Glucose, fructose, galactose
Sketch & label a molecule of each of these monosaccharides. How do they compare? Write the chemical formula for all three.
These are in your book and on your class handout, they have the same chemical formula but different structures, C6H12O6
Because all 3 simple sugars have the same chemical, but different structural formulas, they are called ______isomers_________.
What are double sugars called? Name & describe the process that forms them.
Disaccharides, formed by a condensation reaction from 2 monomers. Condensation involves the loss of a water molecule to form a bond
Name a disaccharide.
Sucrose, maltose, lactose
What forms a polysaccharide? Name a polysaccharide found in animals. Name 2 found in plants?
A polysaccharide is formed from 5 or more monomers, glycogen is found in animals, and starch and cellulose is found in plants
What chemical reaction formed these large molecule? What reaction would be needed to break these molecules?
Condensation-make bonds ;hydrolysis-break bonds
What are the 4 main elements making up proteins? How many covalent bonds does each of these elements form?
Carbon, hydrogen, oxygen, and nitrogen
What are the monomers of proteins called? How many are there? Name the 4 things bonded to the center carbon of this monomer.
Amino acids, 20, hydrogen carboxyl amino and R group
What is the R-group on glycine? on alanine?
Glycine- H and alanine- CH3
How does a dipeptide form? Sketch the dipeptide formed from glycine and alanine. What molecule had to be removed to join these 2 amino acids?
Condensation reaction, bond is found in book, and water must be removed
What do you call the covalent bonds that hold amino acids together?
Peptide bond
Hydrogen bonding among individual amino acids in a chain cause what effect on the protein's shape?
They cause folding in the chain
When a substrate joins with an enzyme, what effect does this have on chemical bonding of that substrate? Is the enzyme affected temporarily or permanently?
It weakens the substrate's bonds, temporarily affects the enzyme.
When chemical bonds in a substrate are weakened, what effect does this have on activation energy needed to start the reaction?
It lowers the activation energy
After the reaction, what happens to the products? Can the enzyme be re-used & why?
The products are released and they enzyme is ready to be reused since it is not changed by the reaction
Besides temperature, what else can affect how an enzyme works by changing the enzyme's shape? Can the reaction still take place?
pH, no the reaction will be inhibited
Are lipids polar or nonpolar? What happens to lipids when they are placed in water?
Nonpolar, they will not dissolve, they will float
Compared to carbohydrates, what is true about the ratio of carbon & hydrogen atoms to oxygen atoms? If a compound has more bonds, what can it store more of in those bonds?
Lipids have a higher ratio of carbon and hydrogen atoms to oxygen atoms than carbohydrates. More bonds have it store more energy.
Most lipids are made of ______fatty________ acids. Describe their shape. What functional group is found on the head end of the molecule?
Fatty acids are a long carbon chain with a carboxyl group on one end (the head end of the molecule)
2 fatty acids --- palmitic & linoleic. Circle the carboxyl group on the "head" of the molecule. Is this end polar or nonpolar? Will this end be attracted to or repelled by water?
The carboxyl group is the head end, it is polar, and it will be attracted to water since it is hydrophilic.
Are both ends of a fatty acid polar? Explain.
No, only the carboxyl end is polar.
Which end of a fatty acid chain WOULD dissolve in water? Which WOULDN'T?
Carboxyl end would, carbon chain would not
In what type of fatty acid are there only single bonds in the carbon chain? Name one such fatty acid.
Saturated- palmitic acid
What type of bond appears in an unsaturated fatty acid? Give an example of an unsaturated fatty acid. Go back to your fatty acid drawings in question 4 and put a box around the double bond in the unsaturated fatty acid.
A double bond appears, linoleic
Name the 3 groups of complex lipids.
Triglycerides, phospholipids, waxes
What makes up a triglyceride? What is the difference between a saturated & unsaturated triglyceride?
3 fatty acids bonded to glycerol, a saturated triglyceride contains saturated fatty acids, an unsaturated triglyceride is made of unsaturated fatty acids
What type of triglycerides tend to be solids at room temperature & why? Which are liquids & why?
Saturated, they have a higher melting point. Unsaturated have a lower melting point and are liquids at room temp.
What type of triglyceride would this substance be --- vegetable oil? butter & shortening?
Unsaturated- vegetable oil; saturated-butter and shortening
What makes up a phospholipid? How are they different from triglycerides? What main part of a cell is made of phospholipids?
Glycerol, 2 fatty acids, and a phosphate group. They are different since they have a phosphate group instead of a third fatty acid. They compose the cell membrane (lipid bilayer)
What is meant by a lipid bilayer? What makes this such an effective barrier between the inside & the outside of the cell?
2 layers of phospholipids.
Wax is another complex lipid. Describe its structure.
Wax is made of one fatty acid and one alcohol chain.
Waxes are highly ____waterproof_________. Explain how plants make use of this property? animals?
Plants and animals use waxes as a protective layer
What makes up steroids? To what group of organic compounds do steroids belong? How are they used in animals?
Steroids ar emade from 4 fused carbon rings, they are lipids, they are hormones in animals
Name a steroid made by the body.
Give the name & abbreviation for 2 nucleic acids found in cells.
a. DNA-deoxyribonucleic acid
b. RNA-ribonucleic acid
Name the 3 parts to a nucleotide.
1. phosphate group
2. 5 carbon sugar- ribose
3. nitrogenous ring