What is the first law of thermodynamics?

Energy cannot be created or destroyed.

How does the second law of thermodynamics relate to entropy?

Entropy continuously increases in energy transformations.

Enzymes lower activation energy, catalyzing reactions efficiently.

Cellular respiration involves the oxidation of glucose to harvest energy.

Metabolism encompasses energy transformations for life sustenance.

The first law of thermodynamics states that energy cannot be created or destroyed, only converted into different forms, emphasizing the conservation of energy throughout all processes.
Metabolism involves the breakdown of ingested chemical energy into absorbed energy, used for various bodily functions, with inefficiencies resulting in heat production, highlighting the complex and interconnected nature of energy transformation within living organisms.

What is the first law of thermodynamics?
Energy cannot be created or destroyed.
How does the second law of thermodynamics relate to entropy?
Entropy continuously increases in energy transformations.
What role do enzymes play in metabolic reactions?
Enzymes lower activation energy, catalyzing reactions efficiently.
How is energy harvested from food in cellular respiration?
Cellular respiration involves the oxidation of glucose to harvest energy.
How is metabolism defined in biological systems?
Metabolism encompasses energy transformations for life sustenance.

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The first law of thermodynamics states that energy cannot be created or destroyed.
Energy is converted to different forms rather than being created or destroyed.
The second law of thermodynamics asserts that entropy, or disorder, continuously increases.
Order requires energy input, such as in forming a wall from a pile of bricks.
Entropy increases as energy transformations occur spontaneously.
In an open system, energy comes in from the surroundings, maintaining order.
Energy is transferred and moved up the food chain, primarily sourced from the sun.
Endergonic reactions require energy input and are not spontaneous.
Exergonic reactions release energy and increase entropy.
Enzymes lower activation energy, catalyzing reactions efficiently.

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Cellular respiration is the process by which energy is harvested from food, particularly glucose, through oxidation.
The oxidation of glucose involves the movement of electrons, which carry energy to co-enzymes like NAD and FAD.
Enzymes play a crucial role in facilitating the transfer of electrons and the reduction of co-enzymes.
The energy in electrons of glucose ultimately comes from the sun, transferred through photosynthesis in plants.
The process of cellular respiration involves glycolysis, pyruvate oxidation, the Krebs cycle, and the electron transport chain.
Glycolysis produces 2 ATP and 2 NADH, while pyruvate oxidation yields 2 NADH.
The Krebs cycle generates 2 ATP, 6 NADH, and 2 FADH2, contributing to a total net ATP yield of 38.
Metabolism encompasses all biological transformations of energy and matter, sustaining life through the acquisition, rearrangement, and utilization of commodities.
Metabolic rate fluctuates throughout the day, representing the total energy metabolized by an organism per unit time.
Metabolism involves the breakdown of ingested chemical energy into absorbed energy, used for biosynthesis, maintenance, growth, reproduction, and other bodily functions.

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Cells duplicate and maintain status quo, with some energy used for external work and chemical energy generation.
Inefficiencies in biosynthesis, maintenance, and external work result in heat production.
Biosynthesis leads to chemical energy, exported organic matter, and mechanical energy.
Metabolism involves the conversion of fuel and oxygen into carbon dioxide, water, ATP, and heat.
Heat is the primary component of metabolic rate, often overlooked in equations.
Metabolism can be measured indirectly through fuel consumption or directly through oxygen consumption.
Different foods produce varying amounts of heat, with proteins and lipids generating more heat than carbohydrates.
Oxygen consumption is a reliable measure of metabolic rate, especially in humans and animals.
Vital organs like the brain, heart, and kidneys have higher metabolic rates than muscles or other tissues.
Temperature impacts metabolic rates differently in endotherms and ectotherms, with ectotherms matching external temperatures.

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Ectotherms exhibit high metabolic rates in low temperatures and low metabolic rates in high temperatures, while endotherms show the opposite pattern, requiring energy for thermoregulation at extreme temperature ends.