The value of RQ (Respiratory Quotient) is a measure of the ratio between the amount of carbon dioxide produced and the amount of oxygen consumed during respiration. It provides information about the type of respiratory substrate being used by an organism.

Definition of RQ:
RQ can be defined as the ratio of the volume of carbon dioxide produced to the volume of oxygen consumed in respiration.

RQ = VCO2/VO2

Where VCO2 is the volume of carbon dioxide produced and VO2 is the volume of oxygen consumed.

Explanation:

When the respiratory substances are poor in oxygen, it implies that the organism is utilizing anaerobic respiration, where oxygen is not the final electron acceptor. In this case, the value of RQ can be determined as follows:

1. RQ = 0:
When an organism is solely relying on anaerobic respiration, such as during intense exercise or in certain microorganisms, the RQ value can be close to zero. This is because anaerobic respiration produces carbon dioxide without consuming oxygen.

2. RQ = Infinity:
If an organism is not utilizing oxygen at all and is solely relying on fermentation, the RQ value can be considered infinity. Fermentation does not involve the consumption of oxygen, so there is no denominator in the RQ equation.

3. RQ > 1:
When an organism is using a mixture of respiratory substrates, including carbohydrates, fats, and proteins, the RQ value can be greater than 1. This is because the oxidation of carbohydrates produces more carbon dioxide per unit of oxygen consumed compared to the oxidation of fats or proteins.

4. RQ < />
When an organism is primarily utilizing fats as a respiratory substrate, the RQ value can be less than 1. This is because the oxidation of fats produces less carbon dioxide per unit of oxygen consumed compared to the oxidation of carbohydrates.

Summary:

In summary, the value of RQ depends on the type of respiratory substrate being used. When the respiratory substances are poor in oxygen, the RQ value can be zero, infinity, greater than 1, or less than 1, depending on the specific metabolic pathway and substrate utilization of the organism.

The answer is infinity.