4-Propylaminobenzoic acid (PABA) is a strong inhibitor of methanopterin, a key cofactor in the methanogenesis enzymes. From what you have learned about the cow rumen ecology, can you explain why it made cows sick after it was fed to cows? What are your thought about the attempts to reduce methane […]

I am studying Amniota and I was wondering if someone could explain to me the following concepts. I know that the features of Chordata are the notochord, dorsal nerve cords, gill clefts (except for Tunicata); segmented muscles and a post-anal tail. I know that developmentally we are related to echinoderms. […]

In his studies of glucose metabolism by yeast, Louis Pasteur discovered that the sudden addition of oxygen (O2) to a previously anaerobic suspension of yeast in grape juice resulted in a dramatic decrease in the rate of glucose consumption. This “Pasteur effect†can be counteracted by the addition of 2,4-dinitrophenol […]

Mendel and the re-discoverers of genetics Correns, de Vries and Tschermak identified discrete traits whose patterns of inheritance followed interpretable rules.  But most traits found in animals and plants were continuous, not discrete, and tended to mix in offspring – when you cross a Labrador and a poodle (two breeds […]