Mitochondria were prepared from roots, stalks, leaves, and leaf veins of spinach. The mitochondrial preparations were examined for their ability to oxidize glycine via the respiratory chain. It is shown that the glycine-oxidizing capacity is restricted to photosynthetically active tissue. The activity is present in mitochondria from the green parts of the leaves, but not in mitochondria from ro...

In a previous study it was reported that transformed tissue of horseradish (Armoracia lapathifolia Gilib.), obtained by infection of leaf explants with A. tumefaciens, developed two tumour lines with different morphology. One line grew as a completely unorganized tissue (TN – tumour tissue), while the other line grew as a partially organized teratogenous tumour with malformed hyperhydric shoots...

1. The optimal defence theory (ODT) of chemical defence provides a predictive framework for the distribution of anti-herbivore defences in plants. One of its predictions is that chemical defences will be allocated within a plant as a function of tissue value, where value is correlated with the cost of having that tissue removed. While many studies have examined intra-plant variation in defence ...

A novel type of leaf-like poly (p-phenylenediamine) (PpPD) microcrystal was prepared under mild conditions, which was successfully applied to the visual detection of Co(2+)in vitro and in tissue based on the extinction and light scattering features owing to the special etching effect of Co(2+) on the surface of the leaf-like microcrystal.

Here we shall examine the phenomenon of surface-scattered light from both leaves and plant canopies. Results from measurements will show that this surface-scattered light — a quasi-specular reflection if the leaves appear shiny — originates at the interface between the air and the cuticle wax layer. Unlike light that is diffusely reflected by the interior of a leaf, the surface-scattered light ...

There is more than metaphorical appeal to the thought that humanity feeds off the sweat of vascular plants. This statement has factual grounds in the sense that plant water loss by transpiration is an inevitable companion to the photosynthetic process that nourishes the human population. A fascinating corollary of this linkage between water and carbon is that leaf productivity in well-watered p...

We study in situ the mechanics and growth of a leaf. Young Nicotiana tabacum leaves respond to applied mechanical stress by altering both their mechanical properties and the characteristics of their growth. We observed two opposite behaviours, each with its own typical magnitude and timescale. On timescales of the order of minutes, the leaf deforms in response to applied tensile stress. During ...

Objective: To investigate the comparative wound-healing potency of aqueous and methanol leaf extracts of Vernonia arborea Hk. Materials and Methods: Excision, incision and dead space wound models were used to evaluate the wound-healing activity of Vernonia arborea Hk., on Swiss Wistar strain rats of either sex. In excision wound model, treatment was continued till the complete healing of the wo...

Global data sets provide strong evidence of convergence for leaf structure with leaf longevity such that species having thick leaves, low specific leaf area, low mass-based nitrogen concentrations, and low photosynthetic rates typically exhibit long leaf life span. Leaf longevity and corresponding leaf structure have also been widely linked to plant potential growth rate, plant competition, and...

A unique type of vernal pool are those formed on granite outcrops, as the substrate prevents percolation so that water accumulates in depressions when precipitation exceeds evaporation. The O(2) dynamics of small, shallow vernal pools with dense populations of Isoetes australis were studied in situ, and the potential importance of the achlorophyllous leaf bases to underwater net photosynthesis ...