In chemical reactions involving enzymes, the substrate proteins are huge molecules that will only react with each other if they're aligned just the right way. If they are permitted to interact with the enzymes present, the won't collide and react often enough for the reaction to do any good.The enzymes align the molecules, basically acting like "molecule shepherds," showing them the way they need to react.This speeds up the reaction greatly, making things like digestion possible. Hope this is helpful
Answer:
The hemoglobin molecule has four binding sites for oxygen molecules: the iron atoms in the four heme groups. Thus, each Hb tetramer can bind four oxygen molecules.
Answer:
The above paragraphs describes that how salt- and fresh-water fish regulates their osmoregulation. Hence, the correct answer would be c. have adapted to deal with osmosis.
Osmosis is the process by which solvent's molecule move from region of low concentration (hypo-tonic) to the region of high concentration (hyper-tonic) through a semi-permeable membrane.
In sea-water fishes, the body fluids are hypo-tonic to the surrounding water and thus water is kept moving out of their gills. In order to prevent the excess water loss they need to drink water constantly and excrete concentrated urine.
In contrast, fresh-water fishes body fluids are hyper-tonic to surrounding water and hence, water keeps entering in their body through gills. So, in order to prevent excess dilution they absorb salt from surrounding with the help of gills and also their bodies reabsorb salt from urine.
Answer:
The earth is made up of three different layers: the crust, the mantle and the core. This is the outside layer of the earth and is made of solid rock, mostly basalt and granite. There are two types of crust; oceanic and continental. Oceanic crust is denser and thinner and mainly composed of basalt. The inner core is made from Iron and Nickel.
Explanation: