The respiratory quotient (RQ), also known as the oxygen-to-carbon dioxide ratio, measures how much oxygen is used during respiration of a certain substrate. Most typical fats have an RQ of around 0.7. Numerous fatty acids are present in the Pisum sativum or pea seed, and these lipids are oxidised during germination. The RQ of a germination of Pisum sativum is therefore around 0.7, which is less than unity.
Any material or living thing has a respiratory quotient, which can be anywhere between 0.7 and 1.0.
Less oxygen is consumed or more carbon dioxide is produced by molecules with greater RQ levels.
A respiratory quotient is a number without dimensions.
The respiratory quotient is used to determine the basal metabolic rate.
The respiratory quotient of carbohydrate oxidation frequently remains low because oxidising carbs requires more oxygen than oxidising fatty molecules.
The presence of insulin in substances raises the respiratory quotient because it improves the lipid storage of compounds during respiration.
Uses for the Respiratory Quotient
RQ are listed below for several respiratory substrates:
RQ = 1.0 for carbohydrates.
The most prevalent respiratory substrates include carbohydrates like glucose. When all of the glucose is oxidised during aerobic respiration, the CO2 production to O2 consumption ratio is 1.0. This indicates that one molecule of CO2 is created and one molecule of O2 is consumed for every molecule of glucose that is metabolised.
Lipids/Fats: RQ 0.7
Lipids, often known as fats, are energising molecules that are also used as respiratory substrates. Compared to carbohydrates, fatty acids create more reduced electron carriers (NADH and FADH2) during cellular respiration. An RQ value of around 0.7 results from a higher oxygen consumption rate in comparison to CO2 production
Respiration in plants is a process that entails the production of energy in plants. This process can simply be described as the intake of Oxygen and the release of Carbon Dioxide as an outcome of the oxidation of complex organic compounds. Though plants do not have any specific organ to balance the process of respiration, their stems, roots, and leaves do this work at a very low rate than other living beings. The process of respiration is very crucial for the plants to sustain the growth of the plant tissues.
This process can be stated as-
\[C_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + \text{Energy}\]