BIOB50H3 Lecture Notes - Lecture 2: Radiant Energy, Parasitic Plant, Chemosynthesis
Document Summary
It"s all about energy everybody needs energy and without it animals cannot grow, reproduce, thermo regulate, move cannot live all metabolic processes require energy. without it, enzymes fail, cell membranes degrade, organelles cease to operate, life is impossible. Energy cannot be recycled. autotrophs assimilate energy from sunlight (photosynthesis) or from inorganic compounds (chemosynthesis) The energy is converted into chemical energy stored in the carbon-carbon bonds of organic molecules: heterotrophs obtain energy by consuming organic compounds from other organisms. Predators capture and consume live prey, parasites and herbivores consume live hosts but may not kill, detritivores consume non-living organic material. Most plants are autotrophs, most animals and fungi are heterotrophs but there are exceptions. Holoparasites, hemiparasites, some animals can acquire chloroplasts through symbiosis or their diet autotrophy. Concept: radiant and chemical energy captured by autotrophs is converted into stored energy in carbon- carbon bonds. Chemosynthesis contributes less energy to ecosystems, but still important for nutrient cycling and in some specalized ecosystems.
