Answer:
In a research there are two variables independent and dependent variable. independent variable is defined as the variable which is controlled and changed in a scientific experiment and evaluate the effects on the dependent variable while the variable which are tested and measured in experiment are called dependent variable.
When antibiotic is sprayed at one side of the petri dish, the bacterial growth on that side will eventually decrease in comparison to other side.
So, the independent variable in this experiment will be antibiotic because it is used to understand the growth of bacteria by decreasing their numbers and the dependent variable in this experiment will be bacteria as they vary according to the change in independent variable that is antibiotic.
Answer:
The primary succession process can take hundreds of years to happen, even in medium amounts of rain and temperature.
Explanation:
The primary succession occurs when a community of plants begins to sprout in areas that have never been occupied by any type of living being. The primary succession occurs, for example, with the sprouting of vegetables in rocky outcrops. These plant species are known as primary species and although they are able to survive, these environments offer few resources for the development of living things. Generally, it takes hundreds and even thousands of years for primary succession to occur, even in environments with average temperature and precipitation.
Answer:
When an organism excretes or dies, nitrogen is in the form of organic nitrogen in its tissues (e.g. amino acids, DNA). During the ammonification process, many fungi and prokaryotes then break the tissue down and release inorganic Nitrogen into the atmosphere as ammonia.
Explanation:
Plants use their roots for nitrogen compounds. When they consume the seeds, animals acquire certain chemicals. When plants and livestock die, or animals excrete waste, the organic nitrogen compounds return to the soil, where microorganisms known as decomposers break down their compounds.
Carbon is the atom, which is necessarily find in the living organism.
All the living organisms are made up of biomolecules. All the biomolecules are organic compounds. The substance cannot be consider as living, if it lacks nucleic acids. There are two types of nucleic acids DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), both have a structure made up of carbon rings and chains.
Other than nucleic acids, proteins, enzymes, hormones etc are also made up of carbon. So, all the living cells, or dead remain of organism must have carbon atom.
Hence, the correct answer is option D. carbon.
