Cellular Respiration Overview

Study Notes

Cellular Respiration

Cellular respiration is the process by which cells break down glucose to produce ATP (adenosine triphosphate), the primary energy currency of cells.
It's a catabolic process that releases energy stored in the chemical bonds of glucose.
There are three main stages: glycolysis, the Krebs cycle (citric acid cycle), and the electron transport chain.
Glycolysis occurs in the cytoplasm and involves the breakdown of glucose into two molecules of pyruvate.
The Krebs cycle takes place in the mitochondrial matrix and further oxidizes pyruvate, producing NADH and FADH2 (electron carriers).
The electron transport chain occurs in the inner mitochondrial membrane. Electron carriers (NADH and FADH2) transfer electrons, creating a proton gradient that drives ATP synthesis through chemiosmosis.
Aerobic respiration requires oxygen as the final electron acceptor in the electron transport chain. Anaerobic respiration (fermentation) occurs without oxygen.
Cellular respiration is highly efficient, producing a significantly larger amount of ATP compared to fermentation.
Different types of cellular respiration exist depending on the starting molecule, but they all involve oxidation and reduction reactions releasing energy and creating usable energy for the cell.

Photosynthesis

Photosynthesis is the process by which plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water.
It's an anabolic process that stores energy from sunlight in the chemical bonds of glucose.
Two main stages: the light-dependent reactions and the light-independent reactions (Calvin cycle).
The light-dependent reactions occur in the thylakoid membranes of chloroplasts. Sunlight energy is captured by chlorophyll and other pigments, splitting water molecules and producing ATP and NADPH.
Oxygen is released as a by-product of water splitting during the light-dependent reactions.
The light-independent reactions (Calvin cycle) occur in the stroma of chloroplasts. ATP and NADPH from the light-dependent reactions provide the energy to convert carbon dioxide into glucose.
Photosynthesis requires carbon dioxide as a source of carbon atoms for glucose synthesis.
The rate of photosynthesis is affected by factors such as light intensity, temperature, and carbon dioxide concentration.
Oxygen is a byproduct of this reaction, and organisms use that process for respiration.
Plants use the glucose produced to fuel cellular processes.
There are different types of photosynthesis including, C3, C4, and CAM, with variations within the pathways of carbon fixation in different places.

Relationship Between Cellular Respiration and Photosynthesis

Photosynthesis and cellular respiration are essentially reverse processes.
Photosynthesis uses sunlight to produce glucose, while cellular respiration breaks down glucose to produce ATP, the energy for cellular processes.
The products of one process are the reactants of the other.
Photosynthesis produces glucose and oxygen. Cellular respiration uses glucose and oxygen and produces carbon dioxide and water.
The interdependence between photosynthesis and cellular respiration is crucial for life on Earth as it cycles essential elements between the living world and the atmosphere.

Description

This quiz covers the essential processes of cellular respiration, including glycolysis, the Krebs cycle, and the electron transport chain. It explores the role of glucose breakdown in ATP production and distinguishes between aerobic and anaerobic respiration. Test your understanding of these fundamental biological processes!