Wow that's a good one :). Think about it like this. When you put antibiotics in place where bacterias live, probably most of them will die, however there might be "some" who are resistent to the antibiotic by their nature, (mutations etc.) so among the bacterias which were exposed the antibiotics those resistent ones will survive. And bacterias have a system for exchanging DNA to make each other more resistant, its called "conjugation" look it up. By conjugation they give each other genes which will help them survive. So if we summarize, those who are already resistant survive (which is a cause of natural selection in an environment of antibiotics) and help others resistant too.
I believe the answer is B. A saturated solution is unable to dissolve any more solvent.
Hope this helps, sorry if I'm wrong.
Answer: 3. adenine (A, green), thymine (T, red), cytosine (C, orange), and guanine (G, blue). 4. adenine (A), cytosine (C), and guanine (G) — are also found in DNA. 5. A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base. The bases used in DNA are adenine (A), cytosine (C), guanine (G), and thymine (T). 6. food crops like soy and corn that have been genetically modified for pest and herbicide resistance. These crops are widely known as “GMOs” (genetically modified organisms). 7. There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine. brainliest?
Explanation:
Answer/Explanation:
(1) a mutation in the coding region, resulting in an inactive protein
To check to see if there is a mutation, you could extract the DNA from the cancer cells and then perform PCR to amplify the gene of interest. You could then perform sanger sequencing and compare the sequence to the normal gene to see if a mutation is present. To test the effect of the mutation, you would want to see if an active protein has been formed.
To see if a normal sized protein has been formed, you could perform a western blot, comparing the protein band to the WT protein band. If the protein is absent or much smaller, it is likely not a functional protein.
(2) epigenetic silencing at the promoter of the gene, resulting in reduced transcription.
To check for changes in the epigenetic landscape of the promoter, you could perform chromatin immunoprecipitation by extracting the chromatin from the tumour cells and using antibodies for different chromatin marks to see what has changed between the normal cells and the tumor cells. E.g. H3K9me3, H3K27me3. You would perform a pull down with the antibody of interest and then PCR for your promoter to specifically look at changes at that gene compared to normal cells. To test DNA methylation, you could perform bisulfite sequencing.
To see how transcription is affected, you could extract RNA from the tumor and normal cells, and compare the levels of RNA between the two samples by qRT-PCR
Answer:
The barrier functions to regulate the chemical composition of the extracellular fluid surrounding the brain cells.
Explanation:
Blood-brain barrier
It is a very selective semipermeable membrane , hence allow some specific substance to pass via it . This barrier separates the extracellular fluid in the central nervous system and the circulating blood from the brain .
<u>The barrier is composed of the endothelial cells .</u>
Passive diffusion is shown in this system , and allows molecules like the water , glucose , amino acid to pass .
It regulates the chemical composition of the fluid of brain cell .
