BSC 1005 Exam 2 Review Graded A+
First Law of Thermodynamics
- Concept: Energy cannot be created or destroyed; it can only be converted or transformed from one
form to another.
Second Law of Thermodynamics
- Concept: Energy transformations are not completely efficient; some energy is lost as heat, which is a
random and less useful form of energy for cells.
Entropy
- Definition: The natural tendency of a system towards disorder or randomness. It is noted that the
overall entropy of the universe is continuously increasing.
Types of Energy
- Potential Energy:
- Refers to stored energy or energy related to an object's position, available to perform work (e.g.,
chemical energy in molecules like ATP).
- Kinetic Energy:
- The energy associated with motion; it is the energy being actively used to do work. Heat is related to
kinetic energy and is a less organized form of energy that cells struggle to utilize effectively.
Chemical Reactions
- Oxidation Reaction:
- The process of losing electrons.
- Reduction Reaction:
- The process of gaining electrons.
- Exergonic Reaction:
, - A type of chemical reaction that releases a net amount of energy. These reactions typically break
down complex molecules; cellular respiration is an example.
- Endergonic Reaction:
- A reaction that requires an input of energy to convert substrates into products, often used to
synthesize complex molecules (e.g., photosynthesis).
ATP (Adenosine Triphosphate)
- Description: ATP serves as the universal energy carrier in all living organisms. It is a modified nucleotide
consisting of an adenine base, ribose sugar, and three phosphate groups.
- Function: ATP provides energy by releasing phosphate groups, a process that is exergonic. Conversely,
synthesizing ATP from ADP involves adding a phosphate group and is endergonic.
Enzymes
- Definition: Enzymes are biological catalysts that speed up chemical reactions without being consumed
in the process; they are primarily made of proteins.
- Mechanism of Action: Enzymes do not change the energy levels of reactants or products; they only
lower the activation energy needed for a reaction to occur.
Cofactors and Coenzymes
- Cofactors: Non-protein helpers that are often small ions (e.g., Fe²⁺, Cu²⁺, Zn²⁺) found at the active sites
of enzymes.
- Coenzymes: Organic molecules that assist in chemical reactions by accepting or donating electrons.
Inhibition Types
- Competitive Inhibition: Occurs when an inhibitor binds to the active site of an enzyme, blocking
substrate binding due to competition for the same space.
First Law of Thermodynamics
- Concept: Energy cannot be created or destroyed; it can only be converted or transformed from one
form to another.
Second Law of Thermodynamics
- Concept: Energy transformations are not completely efficient; some energy is lost as heat, which is a
random and less useful form of energy for cells.
Entropy
- Definition: The natural tendency of a system towards disorder or randomness. It is noted that the
overall entropy of the universe is continuously increasing.
Types of Energy
- Potential Energy:
- Refers to stored energy or energy related to an object's position, available to perform work (e.g.,
chemical energy in molecules like ATP).
- Kinetic Energy:
- The energy associated with motion; it is the energy being actively used to do work. Heat is related to
kinetic energy and is a less organized form of energy that cells struggle to utilize effectively.
Chemical Reactions
- Oxidation Reaction:
- The process of losing electrons.
- Reduction Reaction:
- The process of gaining electrons.
- Exergonic Reaction:
, - A type of chemical reaction that releases a net amount of energy. These reactions typically break
down complex molecules; cellular respiration is an example.
- Endergonic Reaction:
- A reaction that requires an input of energy to convert substrates into products, often used to
synthesize complex molecules (e.g., photosynthesis).
ATP (Adenosine Triphosphate)
- Description: ATP serves as the universal energy carrier in all living organisms. It is a modified nucleotide
consisting of an adenine base, ribose sugar, and three phosphate groups.
- Function: ATP provides energy by releasing phosphate groups, a process that is exergonic. Conversely,
synthesizing ATP from ADP involves adding a phosphate group and is endergonic.
Enzymes
- Definition: Enzymes are biological catalysts that speed up chemical reactions without being consumed
in the process; they are primarily made of proteins.
- Mechanism of Action: Enzymes do not change the energy levels of reactants or products; they only
lower the activation energy needed for a reaction to occur.
Cofactors and Coenzymes
- Cofactors: Non-protein helpers that are often small ions (e.g., Fe²⁺, Cu²⁺, Zn²⁺) found at the active sites
of enzymes.
- Coenzymes: Organic molecules that assist in chemical reactions by accepting or donating electrons.
Inhibition Types
- Competitive Inhibition: Occurs when an inhibitor binds to the active site of an enzyme, blocking
substrate binding due to competition for the same space.
