In fact, the most important characteristic of a desert is that it receives very little rainfall. Most deserts receive less than 300 mm a year compared to rainforests, which receive over 2,000 mm. That means that the desert only gets 10 percent of the rain that a rainforest gets!
Oxygen is a vital element within cellular respiration. An intrinsic part of the cellular respiration cycle is the transfer or electrons through the electron transport chain, and at the end of it exists the mitochondria, in which electrons are donated to the Oxygen and combine with hydrogen ions to form water.
Rigid skeletons are formed from materials including chitin (in arthropods), calcium compounds such as calcium carbonate (in stony corals and mollusks) and silicate (for diatoms and radiolarians).
Builds protein is the correct answer
Crossing over at prophase I results in the linked genes (those on the same chromosome) becoming unlinked and separated. Prophase I is this first stage of meiosis, the chromosomes condense, form tetrads, and exchange DNA. The nucleolus and nuclear envelope disappear.
