Enzymes
Macromolecules
Water
Membrane
Cells
100
Which of the following statements best helps explain the reaction specificity of an enzyme?
The shape and charge of the substrates are compatible with the active site of the enzyme.
Optimal temperature/pH
100
The carbohydrates glucose, galactose, and fructose have the same chemical formula (C-6 H-12 O-6) but different structural formulas.
What is a true statement about glucose, galactose, and fructose?
The carbohydrates have different properties because they have different arrangements of carbon, hydrogen, and oxygen atoms.
They are made up of one or more monosaccharides.
They are used for short term energy.
100
Humans produce sweat as a cooling mechanism to maintain a stable internal temperature. Which of the following best explains how the properties of water contribute to this physiological process?
high heat of vaporization
100
Which macromolecules can be found in a membrane?
Lipids/Proteins
100
Which of the following observations best supports the claim that mitochondria evolved from once-free-living prokaryotic cells by the process of endocytosis?
Mitochondria are surrounded by a double membrane.
Mitochondria have their own DNA.
200
What are the two factors that can denature an enzyme?
Temperature and pH
200
Infected bacteria cells were found to contain significant amounts of radioactive phosphorus but not radioactive sulfur. Which macromolecule was most likely injected into the cells?
Nucleic Acids or DNA/RNA
200
Which of the following best explains the location of the hydrophobic amino acids in the folded protein (in an aqueous solution)?
inside the folds
facing inwards with the hydrophilic amino acids facing outwards
200
Which type of transport will be affected most directly by a temporary shortage of ATP molecules inside the cell?
active transport
200
Which trait describes a feature shown only in prokaryotes?
The organism does not have a nuclear membrane surrounding its genetic material.
No nucleus
Circular DNA (not double helix)
Single-celled
300
pH refers to
how acidic/alkaline something is
how many hydrogen ions are present
300
The synthesis of protein or carbohydrate polymers always produces which of the following as a byproduct?
Water
300
What causes the cohesive property of water?
Hydrogen bonds between the oxygen atom of one water molecule and a hydrogen atom of another water molecule.
300
The scientist built a tube that was divided by an artificial membrane and filled with distilled water. The scientist put a known amount of a protein into the water on one side of the membrane. After some time, the scientist measured the concentration of the protein on either side of the membrane but found that there had been no change.
Why was there no change in concentration on either side of the membrane?
The protein was too big to cross the membrane.
The protein required help/facilitation without energy present.
The protein required help/facilitation with a protein channel to enter.
300
A certain type of specialized cell contains an unusually large amount of rough ER (endoplasmic reticulum). Which of the following functions is this cell type most likely specialized to perform?
producing proteins and packaging proteins for transport
400
What is a control group in an experiment?
a group that is not manipulated at all
a group that is manipulated with a known variable
a group used as baseline data to compare to the experimental groups
400
Identify the process used to form the covalent peptide bonds that join amino acids into a polypeptide.
dehydration synthesis
400
Which part of an amino acid most likely contributes to the hydrophobic behavior?
R group
400
What are the two components of a phospholipid and how are they positioned to form a phospholipid bilayer.
Polar head/ Nonpolar Tail.
Two layers./One layer of polar heads faces outwards of the cell and one layer of polar heads faces inwards of the cell. The nonpolar tails face one another.
400
What is a difference between nucleic acid #1 and nucleic acid #2?
DNA has Thymine/ RNA has Uracil
Double helix/ single stranded
DNA stays in the nucleus.
RNA can travel in and out of the nucleus.
500
How do enzymes speeds up chemical reactions?
They decrease the activation energy of the reaction.
500
How would an amino acid substitution most likely affect the function of a protein?
The protein will not function properly.
The protein will not function at all.
The properties of the protein will change.
All levels of protein structure will change.
500
Water diffuses through these channels in a membrane.
aquaporins
500
how do small lipids like steroids transport in and out of cells?
simple diffusion/ they are small and nonpolar
500
What is the path of a protein in a cell?
DNA instructions in nucleus
mRNA brings the copy of DNA to ribosomes
ribosomes make protein
rough ER packages the protein
golgi apparatus sorts the protein and ships it to
cell membrane as the protein leaves the cell
maybe a vesicle is used to transport the protein in and around the cell