final Flashcards
Which of the following is NOT a characteristic of living organisms?
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a. High degree of complexity and organization
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b. Ability to extract, transform, and use energy
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c. Existence in a thermodynamic equilibrium with their surroundings
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d. Capacity for self-replication and evolution
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Which of the following is a key difference between prokaryotic and eukaryotic cells?
a. Presence of ribosomes
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b. Presence of a plasma membrane
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c. Presence of a membrane-bound nucleus
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d. Presence of genetic material
common functional group found in biomolecules?
amino, hydroxyl, carboxyl
Which of the following statements about chiral molecules in living organisms is true?
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a. They are usually present in both forms (enantiomers).
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b. They are usually present in only one form.
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c. They do not bind stereospecifically.
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d. They have identical physical and chemical properties
hey are usually present in only one form.
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What molecule is thought to have played a key role in the early evolution of life?
RNA
The central dogma of molecular biology describes the flow of genetic information from:
DNA RNA to protein
law of thermodynamics?
a. Energy cannot be created or destroyed. * b. The entropy of a system always increases. Energy can be transformed from one form to another.
What type of thermodynamic system can exchange both matter and energy with its surroundings?
open system
The ultimate source of energy for life on Earth is
sunlight
example of anabolism?
synthesis of protiens from amino acid
Example of catabolism?
cellualr respiration
what is entropy
randomness or disorder
Gibbs free energy (G) combines the concepts of enthalpy and entropy to determine:
spontaneity
reaction is spontaneous if the change in Gibbs free energy (ΔG) is:
negative
What process allows living organisms to drive energetically unfavorable reactions?
energy coupling
The high-energy molecule that is often used for energy coupling in cells is
ATP
What is the difference between ΔG° and ΔG’°?
ΔG° is the standard free-energy change at any pH, while ΔG’° is specific to pH 7.0 (biochemical standard conditions)
An exergonic reaction is characterized by
A negative ΔG’° and a Keq > 1
An endergonic reaction is characterized by:
A positive ΔG’° and a Keq < 1 *
Which of the following statements about catalysts is FALSE? * a. They increase the rate of a chemical reaction. * b. They do not alter ΔG. * c. They lower the activation energy of a reaction. * d. They shift the equilibrium of a reaction.
shift equilibrium of reaction
Feedback inhibition is a type of metabolic regulation wher
The end product of a pathway inhibits an enzyme earlier in the pathway.
The geometry of a water molecule is best described as
Distorted tetrahedron
The dipole moment of water arises from
The unequal sharing of electrons between oxygen and hydrogen.
Hydrogen bonds are:
trong dipole-dipole or charge-dipole interactions
