Field botanists often have clever ways to identify species that are difficult to distinguish from each other without a microscope or reference. Usually the scientific basis or mechanism of such a “test” is unknown, but the test is reliable enough to be widely used. The amount and pattern of cell wall lignification (blue-white fluorescence) in the internal tissues of these two superficially similar looking pine needles has been determined to be the causal basis for the “leaf bending test,” often used to discriminate these two species in the field. Careful biophysical and anatomical analyses revealed that Pinus nigra (top) appears flexible when bent due to a relative lack of internal lignification. Its structural integration causes the leaf structure to fail in compression via a succession of crimping on the flat adaxial face of the leaf. In contrast, Pinus resinosa (bottom) “snaps” at the rounded vertex of the leaf when bent as a result of resistance to tensile forces transmitted through the highly integrated internal leaf tissue, which is provided by the relative abundance of lignification in the walls of the mesophyll cells and the thick lignified periclinal walls of the endodermal cells (Meicenheimer et al., 2008).
This young fruit is of the widely grown garden strawberry variety. The individual “hairs” can be clearly seen. They are the remnant reproductive organs of the individual seeds on the berry’s surface.
Close-up of a broccoli head showing a cluster of immature buds. The tiny pits visible on the surface are stomata, or breathing pores.
Microscopic detail of the surface of a peach. The downy texture of peach skin is due to thousands of hairs, the majority of which are very short. Stomata, or breathing pores, are marked in red.
The black mulberry has been cultivated since antiquity, and is probably originally from China. Here, the microscopic detail shows the individual fruitlets. The hairy texture is withered reproductive organs (stigma).
Cross-section through the leaf of a leek. The spongy tissue, called mesophyll, is typical of leaves. Here the leaf shown magnified is just 1.2 millimeters thick.
This is a close-up of an “eye” of a potato with three emerging shoots, the longest of which is about 4 millimeters long.
This relative to the raspberry and blackberry is native to northern China, Korea and Japan. Curiously, the whole plant, including the sepals that encase the fruit, is covered in sticky hairs.
The edible parts of a cauliflower, shown here at high magnification, are actually fleshy, immature flower heads.
Nakakamiss gumawa ng project na parang High School student lang ang galawan. Parang bata lang ganun. Naalala ko yung scene sa tennis court, takteng nadapa ako, ay mali NASUBSOB AKO ! Yung tawa nila Sir Cabrejas nung sumasayaw si maam masigla na upper body lang talaga yung nagalaw, shet ! PRICELESS ! HAHAHA. I HAD A GREAT TIME WITH BSACC 2-1. IT’S A ONE OF A KIND EXPERIENCE :)) #CalvinCycle #TeamMasiwal #Nagkangkong #Masigla #Photosynthesis #CAM #C4 #Mesophyll