AP Biology : AP Biology
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Example Questions
Example Question #26 : Identify Structure And Purpose Of Carbohydrates, Lipids, Proteins, And Nucleic Acids
Chitin is what class of molecule?
Lipid
Wax
Nucleic acid
Carbohydrate
Carbohydrate
Chitin is a carbohydrate. Specifically, it is a polysaccharide used by arthopods to build exoskeletons, and is found in the cell walls of fungi. Waxes are types of lipids, and nucleic acids are DNA and RNA.
Example Question #26 : Identify Structure And Purpose Of Carbohydrates, Lipids, Proteins, And Nucleic Acids
Starch belongs to which class of macromolecules?
Polypeptides
Lipids
Nucleic acids
Carbohydrates
Carbohydrates
Starch is a carbohydrate. Specifically, it is a polysaccharide carbohydrate used in plants. The enzyme amylase breaks down starch in the mouth and small intestine, where it can is absorbed as monosaccharides and disaccharides.
Example Question #63 : Macromolecules
Which of the following is an example of a lipid?
Disaccharide
Cholesterol
Cellulose
Amino acid
Cholesterol
Cholesterol is a type of steroid, which is a lipid. Amino acids are part of proteins. Cellulose and disaccharides are examples of carbohydrates.
Example Question #63 : Macromolecules
Which of the following includes all the other answer choices?
Fats
Waxes
Phospholipids
Lipids
Lipids
Lipids are a large class of hydrocarbon-based molecules that includes waxes, steroids, phospholipids and fats. Lipids are hydrophobic and have functions in energy storage, providing support to the cell/organism, cell signaling, and make up the majority of the cell membrane.
Example Question #31 : Identify Structure And Purpose Of Carbohydrates, Lipids, Proteins, And Nucleic Acids
A lipid that consists of a long chain of hydrocarbons with the maximum number of hydrogens possible is referred to as __________.
a vitamin
a triglyceride
a steroid
a saturated fatty acid
a saturated fatty acid
Saturated fatty acids contain the maximum number of hydrogens on their hydrocarbon tails. These molecules form long, straight chains that can be very densely packed. By contrast, unsaturated fatty acids, do not contain the maximum number of hydrogens on their hydrocarbon tails, and thus have "kinks" in their tails. This does not allow for dense packing and storage of unsaturated fatty acids, and thus make them easier to burn.
Example Question #32 : Identify Structure And Purpose Of Carbohydrates, Lipids, Proteins, And Nucleic Acids
Hemoglobin is an example of a __________.
steroid
protein
nucleic acid
phospholipid
protein
Hemoglobin is the protein in red blood cells that binds and transports oxygen to the body tissues. It contains an iron core, and each hemoglobin molecule can bind up to four oxygen molecules.
Example Question #2481 : Ap Biology
If a phospholipid's phosphate group is replaced with another fatty acid chain, the result is a __________.
steroid
fat (triglyceride)
wax
saturated fatty acid
fat (triglyceride)
A phospholipid has two fatty acid chains and a phosphate group attached to glycerol. By replacing the phosphate group of a phospholipid with another fatty acid, the result is a glycerol with three fatty acid chains which makes it a fat (triglyceride). Saturated fatty acids are single chains of fatty acids, the resulting molecule has three fatty acids, which each could be saturated or unsaturated. Steroids have structures that consist of four fused carbon rings.
Example Question #34 : Identify Structure And Purpose Of Carbohydrates, Lipids, Proteins, And Nucleic Acids
Fat is composed of which of the following smaller molecules?
None of these
Glycerol and fatty acids
Glycerol
Fatty acids
Glycerol and fatty acids
Fat is made up of glycerol and fatty acids. Specifically, a fat is composed of three fatty acids chains—composed of 16 or 18 carbon atoms in length—connected to a glycerol by way of an ester linkage.
Example Question #2482 : Ap Biology
Which of the following best describes the composition of glycerol molecules?
An alcohol with three carbons each bearing a hydroxyl group
An alcohol with one carbon bearing a hydroxyl group
An alcohol with three carbons without any hydroxyl group
An alcohol with two carbons each bearing a hydroxyl group
An alcohol with three carbons each bearing a hydroxyl group
Glycerol is composed of an alcohol attached to three carbons each bearing a hydroxyl group.
Example Question #2483 : Ap Biology
Fatty acids vary in length and in the number and locations of double bonds between the carbon atoms. If there are no double bonds between the carbon atoms in the tail then the fatty acid is said to be __________.
monounsaturated
unsaturated
low density
saturated
saturated
A saturated fatty acid has no double bonds between the carbon atoms making up the tail of the fatty acid. This lack of double bonding allows for as many hydrogen atoms as possible to be bonded to the carbon skeleton, thus the fatty acid is said to be saturated with hydrogen atoms.
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