Metabolism and Energy Transfer in Biology 6

Practice flashcards for key concepts in metabolism and energy transfer in biology.

What is metabolism?

refers to all chemical reactions of a cell or organism.

What are the two major types of metabolic pathways?

Anabolic pathways, which require energy to synthesize larger molecules, and catabolic pathways, which release energy by breaking down larger molecules.

What is the role of ATP in cellular processes?

acts as the cellular energy currency, providing energy for endergonic reactions.

Define kinetic energy and give an example.

is the energy of motion; for example, a moving car.

Define potential energy and give an example.

is stored energy; for example, water behind a dam.

What is a redox reaction?

is a chemical reaction where electrons are transferred from one molecule to another.

What are endergonic and exergonic reactions?

Endergonic reactions require an input of energy and are nonspontaneous, while exergonic reactions release energy and are spontaneous.

Explain the first law of thermodynamics.

The first law of thermodynamics states that the total amount of energy in the universe is constant; energy cannot be created or destroyed.

What is activation energy?

Activation energy is the energy required for a reaction to proceed.

How do enzymes affect activation energy?

Enzymes lower the activation energy required for reactions, speeding up the reaction rates.

What is feedback inhibition in metabolic pathways?

Feedback inhibition is a regulatory mechanism where the end product of a pathway inhibits an upstream step in the pathway.

What types of modifications can regulate enzyme activity?

Enzyme activity can be regulated by modifications to temperature and/or pH, production of inhibitors or promoters, and availability of coenzymes or cofactors.

What is the difference between competitive and noncompetitive inhibitors?

Competitive inhibitors compete with the substrate for the active site, while noncompetitive inhibitors bind at a different location, reducing the reaction rate.

What is the structure of ATP?

ATP consists of an adenosine backbone and three phosphate groups.

Describe the process of ATP hydrolysis.

ATP hydrolysis releases energy, converting ATP to ADP and inorganic phosphate (Pi), and is reversible.

What is the role of cofactors in enzyme activity?

Cofactors and coenzymes are necessary for some enzymes to function properly, including inorganic ions and organic molecules.

What is bioenergetics?

Bioenergetics is the study of energy flow through living systems.

Discuss the concept of entropy.

Entropy refers to the measure of disorder in a system, and the second law of thermodynamics states that energy transfers increase entropy.

What is the relationship between photosynthesis and metabolic pathways?

Photosynthesis is an anabolic pathway that captures solar energy to synthesize glucose, which is then used in catabolic reactions like cellular respiration.

How do enzymes achieve substrate specificity?

Enzyme specificity is determined by the three-dimensional shape of the enzyme and substrates, particularly at the active site.