The nitrogenous bases found in the DNA are classified into two groups. Identify each of the following examples and/or characteristics as true of Purines or Pyrimidines.

___ 6-membered ring of carbon and nitrogen atoms

___ 5 membered ring fused with a 6 membered ring

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.