an atom is the smallest particle of an element that still has the same chemical properties.
The respiratory system is the organ system that involves breathing. Humans breathe in oxygen. Another way to find the answer is to break down the word respiration. Respiration means "to breathe" or "the action of breathing". The answer is D.
An organism's body is constructed using information in DNA or genetic material in the nucleus of cells.
DNA consists of sequences of nucleotide bases, which can be transcribed into mRNA, tRNA, and rRNA. The RNAs will then be transported to the cytosol of the cell and used in translation, where the codons on mRNA will be translated into specific sequences of polypeptide chains (aka. "immature proteins"), which will then be processed to become functional proteins. These functional proteins will then be the building blocks of the organism's body.
Hope this helps! :)
Plants are photosynthetic. So, they prepare their own food by using raw materials from atmosphere like CO2, H2O and sun’s energy. CO2 is the carbon source for the synthesis of glucose through array of enzyme catalysed biochemical reactions taking place in chloroplast of plant cell.
Animals are heterotrophic in nutrition. So, they get energy; i.e. glucose from the food they eat. It depends on what is their food source. For example, herbivorous animals eat variety of plants, starch and cellulose of which become glucose source. Carnivorous animals eat other animals, whose stored glycogen or fat becomes energy source for them.
