Download Chapter 3 Review Questions

Chapter 2 Review Sheet
Name:_______________________
1. DNA and RNA are examples of ___nucleic acids______________.
2. Carbohydrates and lipids both contain the elements ____carbon__________,
__hydrogen__________, and ________oxygen_________.
3. Proteins are made of ___amino acids________________
4. __polynucleotides or nucleic acids____________ are made of nucleotides.
5. Examples of lipids include _____fats/oils, waxes, hormones (steroids), phospholipids (cell
membrane).
6. Sugars and starches are examples of ____carbohydrates_________________.
7. Muscle, skin, and enzymes are examples of ___proteins___________.
8. Nucleic acids are important because they contain your __genetic information__________.
9. ___Proteins______________ build living tissue and help in chemical reactions.
10. _____Lipids___________ are a source of long-term stored energy.
11. Organic molecules that have the same chemical formula but different structural arrangements
are called __isomers_________.
12. Carbohydrates are important because they __are the main source of energy for living things.
13. Meat, eggs, soy, and beans contain _proteins________.
14. Fruits, vegetables, cereal, and pasta contain _carbohydrates______________.
15. Lipids could be found in these foods: ___meat, vegetables (v. oil), grains (corn oil),
dairy_______.
16. Amino acids are linked by __peptide bonds___________.
17. The __”R”______ group attached to an amino acid determines what kind of amino acid is
present of the 20.
18. __Amino_____ and ______carboxyl__ functional groups are contained within an amino
acid.
19. The carbonyl functional group when located on the end of the compound is called
___carbonyl end (Aldehyde)____________.
20. Proteins will not function properly if they have the wrong __shape__________.
21. An ___enzyme__________ is made of proteins and catalyzes reactions
22. Monomers are linked together by the process of _____polymerization__________.
23. Polymers are broken apart by the process of ___hydrolysis________________.
24. The monomer of a nucleic acid is called a ____nucleotide_______________________.
25. The three parts that make up a nucleotide include _____phosphate group_________,
_______5 carbon sugar____________ and ____nitrogenous base__________.
26. Carbon can bond with so many other things because it has ____4____ valence electrons.
27. Briefly describe each level of structure that results in a 3-dimensional protein
1. Primary – the chain of amino acids that make up the polypeptide
2. Secondary – the chain of amino acids fold to form pleated sheets and an alpha helix.
Hydrogen bonding holds pleats and helix in place
3. Tertiary – sheets and helices fold to form the three dimensional shape of the polypeptide
4. Quaternary – multiple, folded polypeptide subunits combine to form the complete protein
28. Draw an amino acid and label the three main parts that comprise the amino acid.
R Group
29. Explain why people are lactose intolerant. Be sure to include lactose, lactase, and
disaccharide in your response.
People who are lactose intolerant cannot digest the sugar known as lactose. Lactose is a
disaccharide found in milk and products derived from milk. The lactose intolerant person cannot
breakdown lactose into two monosaccharides because they do not have the enzyme lactase.
Lactose passes through their system causing digestion problems.
30. Differentiate between starch, glycogen and cellulose.
Starch – polysaccharide, consisting of many straight chain glucose units connected together.
How plants store energy and excess sugars.
Glycogen – polysaccharide, many glucose units connected together in branched chains, energy
storage molecule for animals, stored in liver and also found in muscle cells.
Cellulose - polysaccharide, many glucose units connected in straight chains and laterally
connected through hydrogen bonding. Primarily found in plants, very strong, provides rigidity
and structure. Is the material that comprises the cell wall. Resembles woven material.
31. Look at the images below. Label the following: monosaccharide, disaccharide,
polysaccharide, amino acid, nucleotide, saturated fatty acid, unsaturated fatty acid,
polyunsaturated fatty acid, and triglyceride (fat).
Monosaccharide
polysaccharide (cellulose)
Disaccharide
Amino Acid
Saturated fatty acid
Fat (triglyceride)
Unsaturated fatty acid
Polyunsaturated fatty acid
Nucleotide
Keystone Practice Questions:
1. Which statement correctly describes how carbon’s ability to form four bonds makes it uniquely
suited to form macromolecules?
A. It forms short, simple carbon chains.
B. It forms large, complex, diverse molecules.
C. It forms covalent bonds with other carbon atoms.
D. It forms covalent bonds that can exist in a single plane.
2. What reaction or process forms a polymer from 2 monomers?
A. glycolysis
B. hydrolysis
C. photosynthesis
D. dehydration synthesis
3. Carbohydrates and proteins are two types of macromolecules. Which functional characteristic of
proteins distinguishes them from carbohydrates?
A. large amount of stored information
B. ability to catalyze biochemical reactions
C. efficient storage of usable chemical energy
D. tendency to make cell membranes hydrophobic
4. Substance A is converted to substance B in a metabolic reaction. Which statement best describes
the role of an enzyme during this reaction?
A. It adjusts the pH of the reaction medium.
B. It provides energy to carry out the reaction.
C. It dissolves substance A in the reaction medium.
D. It speeds up the reaction without being consumed.
5. A scientist observes that, when the pH of the environment surrounding an enzyme is changed, the
rate the enzyme catalyzes a reaction greatly decreases. Which statement best describes how a
change in pH can affect an enzyme?
A. A pH change can cause the enzyme to change its shape.
B. A pH change can remove energy necessary to activate an enzyme.
C. A pH change can add new molecules to the structure of the enzyme.
D. A pH change can cause an enzyme to react with a different substrate.
6. Whenever biological organic compounds, such as proteins and carbohydrates, are broken down or
synthesized...
a. a phase change of matter results.
b. thermal expansion occurs.
c. sunlight is required.
d. energy is absorbed or released.
7. Why does an enzyme function as a catalyst in a reaction?
a. It creates the right pH needed for the reaction.
b. It decreases the amount of energy needed for the reaction.
c. It provides the extra energy needed for the reaction.
d. It maintains the proper temperature needed for the reaction.
Examine the structural formula below.
8. Which of the following macromolecules is best represented by this formula?
a. nucleic acid
c. protein
b. carbohydrate
d. lipid (remember lipids are made of one glycerol (red) and
three long chain fatty acids (blue)
Open-ended Question:
9. Proteins are a major part of every living cell and have many different functions within each cell.
Carbohydrates also perform numerous roles in living things.
Part A: Describe the general composition of a protein molecule.
_____Proteins are made from carbon, oxygen, hydrogen, nitrogen and some have sulfur. These
elements form amino acids. Amino acids form proteins.
Part B: Describe how the structures of proteins differ from the structures of carbohydrates.
______Carbohydrates are in long chains formed by sugars that have bonded together. Proteins
can be in sheets or folded shapes. Carbohydrates only have carbon, hydrogen and oxygen in
them.
Part C: Describe how the functions of proteins differ from the functions of carbohydrates
_________Proteins make up enzymes that speed up reactions in living things. Proteins also
make antibodies, and are responsible for transporting substances into and out of cells.
Carbohydrates give us energy (starch, glycogen) and make up plant cell walls (cellulose)