Answer:
In artificial selection, humans have the capacity to influence certain characteristics of organisms by selective breeding. One can choose desired parental traits determined by genes, which are then passed on to offspring.
Dog breeding is another prime example of artificial selection. Although all dogs are descendants of the wolf, the use of artificial selection has allowed humans to drastically alter the appearance of dogs.
Explanation:
I’ll help you with 20. Freezing happens when the molecules of a liquid get so cold that they slow down enough to hook onto each other, forming a solid crystal. For pure water, this happens at 32 degrees Fahrenheit, and unlike most other solids, ice expands and is actually less dense than water
Answer:
A. Alternative mRNA Splicing
Explanation:
The primary transcript of eukaryotes has introns and exons. The post-transcriptional modification includes splicing of introns and joining of exons to form a mature mRNA.
A single gene can specify two or more related proteins due to the process of alternative splicing of mRNA wherein exons are removed and joined in various combinations which in turn serve as the template for different proteins.
For example, if a primary transcript has 7 exons, the mature mRNA may have all 7 exons or some of them in various combinations. The resultant mRNAs with different combinations of exons would specify different proteins.
Answer:
Cell X
Explanation:
Cell X is the only cell that has chloroplasts, a pigment found in leaf cells of plants / sometimes other parts may have too. Animal cells almost never have chloroplasts
