The Yeshiva World

March 11, 2009 5:59 pm at 5:59 pm #640596

Participant

sometimes when evolutionists twist and turn into ridiculous contortions trying to explain how a clearlycunningly designed complex system could have come about through chaos, they usually are forced to dramatically simplify the supposed chain of events.

for example:

in the above system, in order to initiate the remarkable events the fungus has to first enter the plant, simple right? well: no even miniscually small event in a biological system is simple

here is a sketch as to how the rust fungus enters the plant, even this description is extremely bare boned. dont expect to understand it, just get a taste for it.

When a rust conidium lands on a plant surface, it needs to attach to it, or it would simply be washed off. First, weak, hydrophobic interactions are formed between the spore and the cutin of the plant cell surface. Then unknown signals cause the production of hydrophobic mucilaginous macromolecules called adhesins. These will stick the spore irreversibly to the plant surface.[1] Once attached, the spore will germinate. Rust fungi then penetrate the plant by using the natural opening of the stoma, but first the growing germ tube must locate it. Rust fungi efficiently locate stomata by the use of thigmotropism. The germ tube grows in a random manner until it reaches a ridge between epidermal cells. At this point, it will start to grow perpendicular to the ridge, greatly increasing its chances of locating a stoma.

The stoma is the site of appresorium formation, a structure that functions to both firmly anchor the fungus and aid in penetration.[3] In the rust fungi appresorial formation is controlled by a process of thigmodifferentiation. Appresoria are formed when the germ tube detects ridges that match the dimensions of the stomatal lips of its host species.

It has been proposed that this process is mediated by a mechanosensitive calcium ion channel that is located at the germ tube tip. This ion channel would transduce the stretching of the cell membrane caused by changes in leaf topography into ion fluxes that lead to changes in gene expression and appresorium formation.[4]. This theory is supported by experiments that show that applying Ca2+ externally to the germ tube causes differentiation.

From the appresorium an infection peg grows down into the plant and between the mesophyll cells.

Rust fungi are biotrophs, meaning they gain their nutrients from living cells. This requires a specialised entension of the fungus into a living plant cell called a haustorium. This develops from a haustorial mother cell. The plant cell membrane invaginates around the main haustorial body and the space between the two membranes becomes known as the extra-haustorial matrix. An iron and phosphorus rich neck band bridges the plant and fungal membranes and acts as a seal preventing the escape of nutrients into the plant apoplast. The haustorium contains amino acid and hexose sugar transporters and H+-ATPases for the active transport of nutrients from the plant cell.[5]

The rust fungus will then continue to grow and invade the plant until it is ready for sporulation.

this is just a bare sketch of our very limited knowledge of just the tiny beginning of a gigantic complex, miraculous invasion