Answer: D. Extinctions occur at higher rates during times of ecological stress when populations and species are poorly adapted.
Answer:
e) B and C
Explanation:
Allosteric regulation occurs at these points where the concentration of the substrate and/or products is important for the activation and inhibition of the enzyme.
Erosion of sand n dirt and it ca cause sinkholes
The correct answer is that "the T cell enters a state of anergy".
The activation of T cells requires two signals: (1) antigen specific signal presented by an antigen presenting cell (either a macrophage or a dendritic cell) that activates t cell receptors and (2) co-stimulatory signals that is not antigen specific but rather found in the plasma membrane of the antigen presenting cell (i.e. CD28). In the absence of a co-stimulatory signal, the t cell will enter a state of anergy or the inability to produce an immune response toward an offending antigen.
Answer:
Minerals
Explanation:
Gases are natural and in the ground, metals are also in the ground as are non metals -just look at dirt- and minerals are usually found in geodes, which are usually fallen bits of asteroid and meteorite that has survived earth's atmosphere
