Biomolecules
When lactose is digested by the human body, each lactose molecule is broken down into smaller molecules. To which of the following categories of molecules do these smaller molecules belong?
monosaccharides
A sugar, a phosphate group, and a nitrogen base form the building blocks of which organic compound? *
nucleic acids
The PRIMARY structure of a cell membrane is composed of —
phospholipids.
What type of carbon-based molecule is the first to be broken down by the body's cells to provide a source of energy? *
Carbohydrates
Many plants have waxy coatings on some surfaces. This coating reduces water loss because it is not water-permeable. This waxy coating is which of the following types of organic molecule?
Lipid
Which of the following molecules provides the greatest amount of energy per gram of mass when metabolized? *
Lipid
Lemurs' bodies are adapted to efficiently store energy for times when food is scarce. Which of the following types of molecules are primarily used for long-term energy storage in the lemur? *
Lipids
Which of the following is NOT a carbohydrate? *
Lipids
Glucose is a building block of carbohydrates. Which of these best describes glucose? *
Monosaccharide
Many land plants store energy in starch. When energy is needed, the starch molecules can be broken down quickly. This chemical reaction produces which of the following?
Monosaccharides
Like complex carbohydrates, proteins are biomolecules that serve many functions and can be chemically broken down and restructured. Both proteins and complex carbohydrates are which of the following? *
Polymers of smaller subunits
Since fibrinogen is made of chains of amino acids, it is an example of which type of organic molecule?
Protein
A dog gets many nutrients from its food including amino acids. Which of these can be built directly using the amino acids? *
Proteins
Is it more difficult for your body to break down simple carbohydrates or complex carbohydrates? *
Simple carbohydrates are easier to break down because they consist of only one or two sugar molecules.
A phospholipid bilayer is the central component of cell membranes, which water molecules cannot freely pass through. What characteristics of the phospholipid bilayer prevent water from freely crossing? *
The exterior of the membrane is hydrophilic, but the interior is hydrophobic, keeping water from passing.
Hydrogen bonds help hold the nitrogenous bases of the DNA molecules together. What would likely happen if the hydrogen bonds in DNA were broken? *
The loss of bonds would tear the DNA strands apart.
Why are carbohydrates important to the human body? *
They act as the body's primary energy source.
What do disaccharides, such as sucrose, and polysaccharides, such as starch, have in common?
They are carbohydrates made of simple sugars.
Which of these describes a polymer? *
large molecule made of smaller subunits
Ovalbumin is a protein found in eggs. Which of the following best describes the molecular structure of ovalbumin?
a chain of amino acids folded and twisted into a molecule
Which of these describes the structure of a nucleic acid? *
a chain of monomers composed of a sugar, a phosphate group, and a nitrogenous base
Which bonds could a single carbon atom have? *
a triple bond and a single bond
Proteins are long chains or polymers made up of *
amino acids
Protein synthesis is a major function of living cells. The type of protein synthesized by a cell is determined by the sequence of —
amino acids.
When an animal has to survive without food for a long time, it will eventually break down proteins for energy. However, this process occurs only after exhausting the animal's reserves of phospholipids
carbohydrates and lipids.
All carbohydrates are made of —
carbon, hydrogen, and oxygen.
The genetic material of an organism is composed of
deoxyribonucleic acids.
When fatty acids cannot pack together tightly enough to make a solid fat, they have ________. *
fewer hydrogen atoms
Which of these describes the primary structure of a protein?
the sequence of the amino acids in the protein
