The influence of auxin on respiration of the Avena coleoptile

During photosynthesis, plants acquire the necessary carbon dioxide and release the produced oxygen back into the atmosphere. Openings in the epidermis of plant leaves is the site of this exchange of gasses. A single opening is called a stoma—derived from the Greek word for “mouth.” Stomata open and close in response to a variety of environmental cues.

Chemical factors such as changing CO2, O2, and H+ levels in arterial blood play a critical role in influencing respiration depth and rates. These variations are detected by chemoreceptors—specialized sensors located in two primary body areas. Central chemoreceptors are found throughout the brain stem, including the ventrolateral medulla, while peripheral chemoreceptors are located in the aortic arch and carotid arteries.
CO2 has a potent influence on respiration and is strictly regulated. Under...

Respiration is a crucial physiological function involving exchanging oxygen (O2) and carbon dioxide (CO2) between an organism and its environment. Various factors can impact this essential process:

Plant cells communicate to coordinate their cycle of growth, flowering and fruiting, and activities in roots, shoots, and leaves in response to the changing environmental conditions. Plant signaling is distinct from animal signaling. Plants primarily utilize enzyme-linked receptors, whereas the largest class of cell-surface receptors in animals are G-protein coupled receptors (GPCRs). Unlike animals, receptor tyrosine kinases are rare in plants. Instead, plants have a diverse class of...

Breathing is primarily an involuntary activity regulated by the brainstem respiratory centers. However, it can also be consciously controlled, allowing us to hold our breath or take deeper breaths when needed. This voluntary control is facilitated by the cerebral motor cortex, which bypasses the medullary centers to stimulate the respiratory muscles directly.
However, the ability to hold one's breath voluntarily is not limitless. When the CO2 concentration in the blood reaches a critical level,...

Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.