1.carbon 2oxygen 3.nitrogen is an element found in all organic molecules. during respiration, animals excrete it as a gas known as . 1 nh4 2 o2 3. co2

1st=Carbon

2nd=CO2

Hope it's right!

1. Carbon

2. CO2

Explanation:

1. All living things are made of inorganic molecules mainly carbon and hydrogen. These two elements form the backbone of hydrocarbons which are considered as the building block of living things

2.During respiration in living beings (animals and human beings), the oxidation of carbohydrates takes place  in which glucose is break down into carbon dioxide and water.  

ans.

dna fingerprinting is defined as a process that determines the dna characteristics of an individual. these dna characteristics are unique among individuals as their fingerprints, so it is known as dna fingerprinting.

steps of dna fingerprinting includes extraction of dna from sample, amplification of dna, restriction digestion of amplified dna, and then analysis of dna by gel electrophoresis, respectively.

thus, the next step performed by the scientist is 'to cut the amplified dna (obtained by polymerase chain reaction) by restriction enzymes that cleave the dna into fragments and their analysis.'

it is a. i hope this .