Answer:
horsetails, ferns, gymnosperms
The correct answer is - A. 780 GtC.
If the inputs and outputs of carbon are as shown on the image, than the carbon levels in the atmosphere will reduce by 20 GtC in a ten year time, thus making the atmosphere have 780 GtC instead of the initial 800 GtC.
On the image we can see that the carbon that gets up into the atmosphere is 69 GtC annually, while the carbon that returns on the Earth is 71 GtC annually. That means a drop of 2 GtC annually in the carbon levels in the atmosphere.
Such a process will reduce the Greenhouse effect, and eventually it will lead to an ice age because the atmosphere will not be able to retain as much heat as previously, thus the Earth will cool off.
Answer:
the answer is B, The activation energy must be reached.
Explanation:
Answer:
4. calcium ion and cAMP
Explanation:
Second messengers are the intracellular chemicals that are produced for signal transduction and generation of cellular response when a water-soluble hormone binds to its cell surface receptors. Since water-soluble signaling molecules such as protein hormones cannot cross the cell membranes of their target cells, their binding to the respective receptors triggers the production of an intracellular second messenger. The most common second messenger molecules are cAMP and calcium ions. For example, protein hormones bind to their G-protein linked membrane receptors and trigger the synthesis of cAMP in their target cells.