Respiration during development

Figure 3 shows the hypothetical kinetics of growth, respiration and relative hormone levels in a climacteric fruit at different stages of its life cycle. Hypothetical hormone levels during development and ripening have been speculated on before (13). The rationale for this outline is based on the known influences of the various hormones on cell division,... 

Plants and their individual parts display distinct patterns in their respiratory rate during development. One of the earliest studies on respiratory patterns was conducted on sunflower plants and component parts during an entire growing season (Kidd et al., 1921). In Jerusalem artichokes, total carbon respired from the leaves was calculated from the respiratory rate of different aged leaves x their weight (Hogetsu et al., 1960). The vertical distribution of leaf size (g dwt) and respiratory losses... 

Chen AK, Hedrick MS. Role of glutamate and substance P in the amphibian respiratory network during development Respir Physiol Neurobiol. 2008 162 24-31. 

Miller MJ, Haxhiu MA, Haxhiu-Poskurica B, DreshaJ lA, Difiore JM, Martin RJ. Recurrent hypoxic exposure and reflex responses during development in the piglet. Respir Physiol 2000 123 51-61. 

Fig. 10.8. Evolution of respiration during grape development (Harris et al 1971). , respiratory qnotient , respiratory intensity...

Respiration of the developing peanut is very rapid during fat synthesis but declines before maturity (72) studies of respiration indicate another decline about 8—10 hours after the harvest of peanuts (73). 

As noted earlier, air-velocity profiles during inhalation and exhalation are approximately uniform and partially developed or fully developed, depending on the airway generation, tidal volume, and respiration rate. Similarly, the concentration profiles of the pollutant in the airway lumen may be approximated by uniform partially developed or fully developed concentration profiles in rigid cylindrical tubes. In each airway, the simultaneous action of convection, axial diffusion, and radial diffusion determines a differential mass-balance equation. The gas-concentration profiles are obtained from this equation with appropriate boundary conditions. The flux or transfer rate of the gas to the mucus boundary and axially down the airway can be calculated from these concentration gradients. In a simpler approach, fixed velocity and concentration profiles are assumed, and separate mass balances can be written directly for convection, axial diffusion, and radial diffusion. The latter technique was applied by McJilton et al. 

Both the time of analysis and experimental design may affect the results. An explanation for the increase in adenylates under the conditions of our experiment is still needed. Since both ATP alone and total adenylate concentrations have increased, it does not appear that a shift in phosphorylation can account for the increases. The decrease in photosynthesis and increase in adenylates occur during the same time period and both factors return to normal after 21 hr. From previous research we know that the photosynthetic levels of ozonated pinto bean foliage decrease immediately after ozone exposure even when symptoms do not develop ( ). This does not hold true for the adenylate or respiration responses. Therefore, it appears that the ozone-initiated increase in adenylates is not correlated directly to the photosynthetic response. The increase in respiration persists when adenylate content and photosynthetic rates have returned to normal. Impaired mitochondrial function appears to be a secondary response more closely related to symptom development. 

---