Cellular Respiration Overview and Vocabulary

Cellular Respiration Overview

• Cellular respiration is a process where cells release energy from organic compounds to produce ATP.
• The process involves breaking down glucose to release energy, using oxygen.
• The main product of cellular respiration is ATP, a usable form of energy.

Cellular Respiration Vocabulary

• Aerobic respiration: Requires oxygen, a highly efficient process.
• Anaerobic respiration (fermentation): Does not require oxygen, less efficient process, short-term usage only.
• Glycolysis: The first step in both aerobic and anaerobic respiration, takes place in the cytoplasm, breaking down glucose into pyruvate.
• Krebs cycle (citric acid cycle): Part of aerobic respiration, takes place in the mitochondrial matrix, further breaking down pyruvate.
• Electron transport chain (ETC): Final part of aerobic respiration, involves a series of protein complexes in the inner mitochondrial membrane, producing a large amount of ATP.
• Mitochondria: Organelles where cellular respiration primarily occurs, often called the "powerhouses" of the cell.
• ATP: Adenosine triphosphate, a crucial energy carrier molecule.
• ADP: Adenosine diphosphate, a low-energy form of ATP that converts to high-energy ATP through cellular respiration.
• NADH and FADH2: Electron carriers that transport high-energy electrons to the electron transport chain during cellular respiration.

Steps in Aerobic Respiration

• Glycolysis: Occurs in the cytoplasm. Glucose is broken down into two pyruvate molecules, producing 2 ATP and 2 NADH.
• Preparatory Reaction: Before entering the Krebs cycle, pyruvate is converted to Acetyl CoA and CO2 is released. This step produces 2 NADH
• Krebs Cycle: Occurs in the mitochondrial matrix. Acetyl CoA is further oxidized, releasing CO2, producing 2 ATP, 6NADH, and 2 FADH2.
• Electron Transport Chain (ETC): Electrons from NADH and FADH2 are passed along the ETC, creating a proton gradient. This gradient drives ATP synthesis by ATP synthase, producing a large amount of ATP (32-34 ATP). Oxygen is the final electron acceptor, forming water.

Key Facts

• The overall chemical equation of aerobic cellular respiration is: Glucose + Oxygen → Carbon Dioxide + Water + Energy (ATP)
• Most eukaryotes, including animals, plants and fungi rely on aerobic respiration.
• Cellular respiration and photosynthesis are interdependent processes. In Photosynthesis, autotrophs use sunlight to convert carbon dioxide and water into glucose and oxygen. In cellular respiration, the glucose is broken down releasing energy and releasing oxygen

Comparisons between Photosynthesis and Cellular Respiration

• Opposite Processes: Photosynthesis takes in carbon dioxide and releases oxygen, while cellular respiration takes in oxygen and releases carbon dioxide.
• Energy Conversion: Photosynthesis stores energy in sugar molecules, while cellular respiration releases energy from sugar molecules.

Parts of the Mitochondria

• Outer membrane: Provides protection
• Inner membrane: Highly folded into cristae to increase surface area for electron transport chain
• Intermembrane space: The area between the outer and inner membranes.
• Matrix: The fluid-filled space inside the inner membrane, where the Krebs cycle occurs

This quiz delves into the process of cellular respiration, emphasizing how cells release energy and produce ATP from organic compounds. It covers key vocabulary, including aerobic and anaerobic respiration, glycolysis, Krebs cycle, and the electron transport chain. Understand the significance of these processes in energy production.