Question

Summary

Cellular respiration converts glucose to energy that cells can actually use. Without it, the energy molecule could not transfer its energy to our cells. It may not sound like much, but this transfer of energy allows us to move our muscles, blink our eyes, or think for that matter. Cellular respiration makes carbon dioxide as a by-product. But don't worry; photosynthesis can turn that carbon dioxide to food and oxygen in less time than it takes you to finish reading this sentence.

Think Like a Scientist
Now that you have learned about cellular respiration, you should be able to answer the following focus questions:

What components are involved in the process of cellular respiration?
What are the steps and structures involved in the process of cellular respiration?
Talk Like a Scientist
There are new vocabulary terms in this lesson:

Cellular respiration: a set of processes that convert biochemical energy from glucose into an energy molecule that is stored for later use
Metabolic process: an organic process in a cell or organism that is necessary for life
Mitochondria: special structures found in most cells where cellular respiration and energy production take place

Answer 1

Components involved in the process of cellular respiration include glucose (a sugar molecule), oxygen, and enzymes. Glucose serves as the initial fuel source for cellular respiration, while oxygen acts as the final electron acceptor in the electron transport chain.

The process of cellular respiration consists of three main steps: glycolysis, the Krebs cycle (also known as the citric acid cycle), and oxidative phosphorylation (which includes the electron transport chain). These steps occur in different parts of the cell, primarily in the cytoplasm and mitochondria.

1. Glycolysis: This occurs in the cytoplasm and involves the breakdown of glucose into two molecules of pyruvate. It generates a small amount of ATP (adenosine triphosphate) and NADH (nicotinamide adenine dinucleotide).

2. Krebs cycle: This takes place in the mitochondria and involves the further breakdown of pyruvate into carbon dioxide. It generates ATP, NADH, and FADH2 (flavin adenine dinucleotide).

3. Oxidative phosphorylation: This occurs in the inner membrane of the mitochondria. It involves the transfer of electrons from NADH and FADH2 to the electron transport chain, which generates a large amount of ATP through a process called chemiosmosis. Oxygen is the final electron acceptor, and water is produced as a by-product.

Mitochondria play a crucial role in cellular respiration as they house the enzymes and structures necessary for the process to occur. They have an inner and outer membrane, with the inner membrane containing the electron transport chain and ATP synthase, which produces ATP.

Overall, cellular respiration is an essential metabolic process that converts the energy stored in glucose into ATP, providing the energy needed for various cellular activities and functions.