Answer:
B) Nutrient B only
Explanation:
According to the given information, A, B, and C are required for the normal growth of the organism. The mutant strain has mutated gene A and therefore, can not convert the A into B. However, the given mutation strain is able to convert B into C. If the mutant strain is supplemented with "B", it would be able to form C. In absence of "B" in the medium, the strain would not be able to form both B and C. Therefore, presence of "B" is required in the medium for the given mutant strain.
The answer would be B. To get the type of data Darwin needed, you would have to go out into the field and observe. He isn't plugging numbers into a math equation, he wasn't experimenting with sulfur and hydrogen, he wasn't sitting in a lab, he was in the field.
The three<span> main </span>reasons<span> why </span>cell division is importantin organisms are reproduction, repair and growth ,<span>Heredity</span>
Answer:
By using the subsets.
Explanation:
Evolution is the change in the species characteristics with the changing environment and the passage of the time. Different ideas has been put forward by the scientists to study the evolution.
The organization of the trait groups can be done by using the different subsets. Different sets can be used for example A and B. The set A that is used can be used as the subset of the B group and vice-versa. The traits present in the A set must be present in the B subset as well.
Thus, the answer is by using the subsets.
Ans.
Different barriers present in the body prevent entry of disease causing agents or pathogens from entering into body and provide protection against them. These barriers include various physical, chemical, and biological barriers.
Physical barrier include skin and coughing and sneezing. Skin provides first line of defense by preventing entry of pathogens, and coughing and sneezing that expels harmful agents out of the body.
Chemical barriers include lysozyme, acids, and oil secretion. Lysozyme is an enzyme that kills bacteria by targeting their cell wall, while oil and acid prevent microbial growth by providing non-favorable environment for them.
Biological barriers include phagocytes and Langerhans cells. Phagocytes are immune cells that engulf and destroy pathogens and Langerhans cells are antigen-presenting cells that help in elimination of pathogens.