Answer:
The most important abiotic factors include water, sunlight, oxygen, soil and temperature. Water (H2O) is a very important abiotic factor – it is often said that “water is life.” All living organisms need water.
Answer: Helps the plant breathe: The epidermis of the leaf contains guard cells that control and regulate the small pores on the undersurface of the leaves. These pores are called stomata. Stomata are responsible for regulating water in and out of the cell. It is also responsible for the exchange of gases across the epidermis.
Answer:
Yeah, so basically the image is showing restriction enzymes. The job of restriction enzymes is mainly involved in research when scientists use them for cloning human genes. But that's besides the point...
Main thing you have to understand is that restriction enzymes cut at very specific places along DNA sequences. If you look at the restriction enzyme Rsa 1, you can notice that it cuts only between a thymine nucleotide base and an adenine nucleotide base. Next, if ya look at Sty 1 (be careful b/c W can represent adenine or thymine), it cuts only between two directly adjacent cytosine nucleotide bases!
SO.... if we go to Rsa 1, we can find the answers by dividing up the sequences between the pattern we saw in the gray box. It only cuts between adenine and thymine bases. Based on that, we can find the number of fragments created, and the segment lengths (basically just like how many nucleotide bases are in each strand). Hope ya found this helpful!
Addition or deletion of nucleotides in any number besides 3 results in a "frame-shift mutation."
This is because every 3 nucleotides of DNA/mRNA exons codes for a single amino acid in the synthesis of a protein. This triplet codon theory means that if 3 nucleotides are added or deleted then an amino acid will be added or lost, but subsequent codons and amino acids will still be read correctly.
However, if any number of nucleotides other than 3 are added or removed, then the codons following the mutation will be out of "sync," in terms of the reading order.
Hence it is called a frame-shift mutation because it shift the reading frame when translating nucleic acids into proteins. Frame shifts will lead to the wrong amino acids being adding in the wrong order for the rest of the code after the mutation.