BIOLOGY HELP
1-The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called ________________ they ________________ perform their usual functions.
naturation/can | |
naturation/cannot | |
denaturation/can | |
denaturation/cannot | |
dehydration reaction/cannot |
2-Which group of lipids will contain hydrophilic heads that face outwards and hydrophobic tails that face inwards that will form a barrier?
phospholipids | |
steroids | |
triglycerides | |
saturated acids | |
trans-fatty acids |
3-DNA codes for the sequence of amino acids in the primary structure of a protein, but not for sugars or lipids. This is because
only proteins are involved in living metabolic reactions. | |
sugars and lipids code for their own replication. | |
sugars and lipids are ever present in the living environment and are not used in living structures. | |
other hereditary molecules code for sugars and lipids. | |
proteins are the main structural and functional components of cells. |
4-Which statement about the cellular nucleic acids DNA and RNA is incorrect?
DNA is double-stranded, and RNA is single-stranded. | |
The sugar in DNA is deoxyribose, and in RNA the sugar is ribose. | |
DNA has a helix shape; RNA does not. | |
RNA and DNA have the same four nitrogen-containing bases. | |
Both DNA and RNA are polymers of nucleotides. |
5-All carbohydrate molecules
contain amino acids. | |
contain nitrogen and phosphate. | |
are organic acids. | |
are composed of atoms of C, H, and the functional group -OH. | |
are composed of atoms of C, H, O, and N. |
6-Two molecules of glucose combine to form a disaccharide molecule during a(n) ________ reaction.
dehydration | |
hydrolysis | |
hydrogen bond | |
ionic bond | |
inert |
7-One carbon atom can form covalent bonds with up to ___ other atoms to form an organic molecule.
2 | |
3 | |
4 | |
6 | |
8 |
8-Enzymes are organic compounds classified as
nucleic acids. | |
carbohydrates. | |
lipids. | |
steroids. | |
proteins. |
9-Organic molecules
always contain carbon. | |
always contain hydrogen. | |
always contain carbon and hydrogen. | |
are found only in organisms, hence their name. | |
are always food molecules.
|
10-The water strider is an insect that skates across the water without sinking. The tips of its feet must be coated with molecules that are
ions. | |
hydrophilic. | |
hydrophobic. | |
basic. | |
acidic. |
11-Nucleic acids are polymers of
amino acids. | |
nucleotides. | |
glycerol. | |
monosaccharides. | |
fatty acids. |
12-DNA codes for the sequence of amino acids in the primary structure of a protein, but not for sugars or lipids. This is because
only proteins are involved in living metabolic reactions. | |
sugars and lipids code for their own replication. | |
sugars and lipids are ever present in the living environment and are not used in living structures. | |
other hereditary molecules code for sugars and lipids. | |
proteins are the main structural and functional components of cells. |
13-The moon lacks life and varies dramatically in temperature. If we could keep a layer of water spread on the surface of the moon, what effect would it have?
Life would be possible but it would have to withstand these extremes in temperature. | |
Water would absorb and hold heat and moderate the temperature extremes. | |
The temperatures would drop to the lower extremes. | |
Because water has a high heat of vaporization, the temperatures would rise to the upper extremes. | |
Physical conditions would remain the same. |
14-____ is a polysaccharide that is found in plant cell walls and accounts for their strength.
Cellulose | |
Chitin | |
Glycogen | |
Starch | |
Cholesterol
|
15-The primary function of carbohydrates is
quick fuel and short-term energy storage. | |
structural reinforcement of plant and fungal cell walls. | |
encoding the hereditary information. | |
to speed chemical reactions in cells. | |
to transport molecules across cell membranes. |
16-Which of the following types of lipid is the most abundant constituent of cell membranes?
cholesterol | |
phospholipid | |
triglyceride | |
neutral fat | |
fa |