Answer:
Variations are caused by mutation. random mating between organisms.
Explanation:
A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms.
So there are four types of mountains and these are fault block mountains, fold and thrust mountains, unwarped or dome mountains and volcanic mountains.
Based on the given locations above, the Sierra Nevada mountains of California are fault block mountains. The Alps of Europe is an example of a fold and thrust mountain. The Black Hills of South Dakota and Teton range of Wyoming are unwarped or dome mountains. Hope this answer helps.
Answer:
All errors described will result in a negative result
Explanation:
The enzyme-linked immunosorbent assay (ELISA), is a test used to detect and measure antibodies, antigens and proteins in the blood. An ELISA test uses antibodies and/or antigens that are coupled to an easily-assayed enzyme, thereby this approach combines antibody specificity with the sensitivity of simple enzyme assays. ELISA test involves an antibody or antigen that reacts to form an antigen-antibody complex, where such reaction is interpreted as a positive result. The negative results are evidenced by the lack of reaction, which may be caused by some error during the chain of reactions in the ELISA test: antigen >> primary antibody (reaction) >> functional secondary antibody (reaction) >> conjugated enzyme (reaction) >> functional substrate.
