Mexican redbud (Cercis canadensis ssp. Mexicana) trees have a rounded and dense form that is broad and compact. The stems on Mexican redbuds are thicker than other redbud species, as well as more rigid. They grow 15 to 25 feet tall and have pink to purple spring-blooming flowers. The dark-green, leather-like leaves on Mexican redbud trees grow 2 to 6 inches long and have a glossy appearance as the tree ages.
enzymeâsubstrate complex. A Dictionary of Biology. Â© A Dictionary of Biology 2004, originally published by Oxford University Press 2004. enzymeâsubstrate complex The intermediate formed when a substrate molecule interacts with the active site of an enzyme. Following the formation of an enzymeâsubstrate complex, the substrate molecule undergoes a chemical reaction and is converted into a new product.
Enzymes operate by binding to a substrate or substrates temporarily, lowering the activation energy necessary for a reaction to take place. The catalytic (active) site is the portion of the enzyme where substrate binding occurs. Each enzyme is specific for one or more substrate types. Two different theories about how enzyme-substrate binding exist. In the induced-fit (key and lock) model (a), the active site of an enzyme has a shape specific to the substrate.