Below are the choices:
<span>a. creating an online chat group for asking questions and posting solutions
b. establishing a standard method for delivering the results to the teacher
c. offering a wide variety of rain gauges for everyone to choose from
d. using a standard unit of measure for the duration of the study
</span>
the answer is D. I hope it helps.
The first land plants appeared around 470 million years ago, during the Ordovician period, when life was diversifying rapidly. They were non-vascular plants, like mosses and liverworts, that didn't have deep roots
At least two of the black offspring should be heterozygous
Plant roots usually grow downwards, sprawling out as they collect water in the soil.
Answer:
The correct option is C. receptor dimerizaton.
Explanation:
Growth Factors are protein substances found in our blood and play an important role in intercellular communication. These protein substances bind to receptors on the surface of the cell, with the main result of the activation of cell proliferation and / or differentiation. Many growth factors are very versatile, stimulating cell division in numerous different cell types, while others are specific to a particular cell type.
For the activation of a growth factor, dimerization or oligomerization of the receptor is necessary for kinase activity to occur, triggering intracellular signaling cascades. The dimerization can be between two identical receptors (homodimerization) or between different members of the same family (heterodimerization). The dimerization of the receptor, leads to the activation of its tyrosine kinase and the transphosphorylation of the tyrosine residues, releasing a signal transduction into the cell.
