Redwood tree

Aspergillus parasiticus is an endophyte isolated from the inner bark of the redwood tree. Sequoia sempervirens (Taxodiaceae). Previously, several sequoaitones active in the brine shrimp toxicity assay were isolated from this fungal strain and more recently four new sequoaitones C — F (49—52) were isolated and found to be toxic to brine shrimp with LD50 of260 p,M, 1300 xM, 640 xM, and 260 p.M, respectively. ... 

If the coefficient of interfacial tension between air and water is y = 74 dyn/cm, what diameter capillary is needed to raise water to a height of 100 m Does this seem reasonable for, say, redwood trees If not, what other mechanisms might be at work ... 

Lovelock defines Earth as a living organism, first of all, because of its homeostatic properties. But he draws also some other analogies to show how close the concept of Gaia is linked with the concept of life. Perhaps the most illustrative is his morphological redwood tree - argument. The tree undoubtedly is alive, yet 99 percent is dead" (Lovelock, 1989b, p, 27). Dead wood of a tree can be compared with the apparently inanimate rocks of the Earth. 

Redwood tree (Photographer Allie Caulfield from Germany)... 

Living organisms are amazingly complex. A myriad of chemical reactions take place every second in every organism on Earth, from simple one-celled bacteria to chimpanzees, elephants, redwood trees, and human beings. Much of human health revolves around maintaining a proper balance of the chemicals found in our bodies. The more a person understands about the principles of chemistry as appUed to biochemical processes, the more he or she will be able to optimize his or her own health. 

It is often asked how it is possible for a tall tree to get liquid (sap) to the top. One answer regularly given is that it is done by osmotic pressure. Is that possible The tallest trees in the world are the redwood trees in California of which the tallest one measured to date is 367 feet tall. 

Mechanical strength is a property generally associated with secondary walls these walls contain substantial deposits of cellulose microfibrils and lignin, a highly cross-linked phenolic polymer that is synthesized and covalently linked into the wall at the cessation of cell expansion. Secondary walls allow plants to exploit the aerial environment and account for the ability of eucalyptus and redwood trees to reach heights of more than 100 m. 

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