<h2>b) option is correct </h2>
Explanation:
- Some bacterial toxins cause disease by altering the activity of G protein, cholera toxin is one of them
- Cholera toxin catalyse ADP ribosylation of Gs and blocks GTPase activity thus Gs GTP become permanently active
- Constitutive activation of Gs protein continuously induce adenylyl cyclase, cytosolic cAMP level rises that leads to activation of protein kinase A (pKA)
- Activated pKA catalyse phosphorylation of two transmembrane proteins of intestinal epithelial cells:
- CFTR cause excessive outflow of Cl- ion and Na+ H+ exchange cause efflux of Na+ ion, both enters in gut and form Na+ Cl-
- Na+Cl- leads to outflow of water from the gut, resulting in diarrhea and dehydration and this condition may cause death of organisms due to loss of water and ions
C, if you look at a water wheel, water flows on the wheel, turning a rod, powering something on the inside. Dams do the same thing except the rod goes into a transformer and is more complicated.
Hey there,
<span>Exposing the casted extremity.
Hope this helps :))
~Top
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Adaption, evolution, variation are all causes of natural selection.
hope this helps..
brainliest..?
Answer:
The correct selection of answers to the question: Identify the pieces of evidence describing the features of DNA that Watson and Crick used to determine the structure of DNA, would be:
C: The two chains are parallel, both running in a 5´ to 3´ direction
D: A purine base forms hydrogen bonds to pair with a pyrimidine base located on the opposite DNA strand. Specifically, A pairs with T, and C pairs with G.
E: The sugar-phosphate backbones of each DNA helix run antiparallel to one another
F: The diameter of the DNA doube helix is 2 nm, with each purine-pyrimidine base pair spanning an equivalent distance between the two chains.
Explanation:
Although Watson´s and Crick´s research, and model of the DNA helix, became the breakthrough for science, as it visually presented the now known characteristics of DNA, this research was possible due to the way that these two researchers used previous information found by other scientist on the molecule, to finally build their model. All of the options that were selected were part of the research of several scientis, including Mendel, Rosalin Franklin, Linus Pauling, Maurice Wilkins, Oswald Avery and many others, who worked on different aspects of specimens and their specific characteristics, and which led them to discover that organisms possessed DNA, that this was the unit of information that directed all functions in living cells and how this DNA helix was chemically built to understand how it worked, and why it worked the way it did.
