Answer:
Option A, Key stone
Explanation:
A keystone species plays a major role in an ecosystem as it is the species whose presence effects all other species in the ecosystem .In general a keystone species is always a dominant predator that feed on prey population. If it is removed, the prey population will explode and the population diversity will reduce. For example - bison, prairie dog etc.
Hence, option A is correct
Answer:
Agriculture and domestication probably started in the Fertile Crescent (the Nile Valley, The Levant and Mesopotamia). ... People probably started agriculture slowly by planting a few crops, but still gathered many foods from the wild. People may have started farming because the weather and soil began to change.
Explanation:
-Each layer is younger than the one below it.
I believe the miRNAs control gene expression by binding to mRNAs and degrading them or blocking their translation. The microRNAs are short non coding RNAs which function to regulate the process of gene expression. They bind to the 3-UTR of the target mRNAs and repress the production of protein by destabilizing the mRNA and translational silencing.
Answer:
She will add color dye to antibodies, and the antibodies will attach to the antigen of the pathogen.
Explanation:
Immunostaining is the process where the antibodies for a specific pathological antigen is combined with fluorescent dye or any other indicator, like enzyme. Fluorescein are common staining materials used because it is easily detectable under UV light. This antibody coated with indicator thus bind to the specific pathogen or protein and help in its identification. Also the pathogenic cell fixation is done to facilitates clear and precise identification.
