These <span>large leaves of ferns that show multiple venation are called fronds.</span>
DNA is composed of nucleotides, which are composed of three parts:
1. A five carbon carbohydrate (pentose)
Pentose is classified as a monosaccharide (simple carbohydrate), and its molecular formula is represented by 
. They are water soluble molecules with sweet taste. Monosaccharides may have from three carbon atoms (trioses) to six (hexoses). In DNA is present pentose (5 carbon atoms)
2. A nitrogenous base
Nitrogenous bases are ring-shaped compounds that contain nitrogen in their molecular structure. They are classified into two groups: purines and pyrimidines
The purine bases are adenine (A) and guanine (G). They are larger and contain more than one ring in their structure,.
The pyrimidines, cytosine (C), uracil (U) and thymine (T), are smaller and composed of a single ring.
3. One or more phosphate groups
A phosphate consists of a trivalent anion that contains one phosphorus atom and four oxygen atoms. Its molecular formula is expressed by 
.
I would say Diandra, because she provides the most in depth description!
Answer:
The colonies are carrying the resistance genes from plasmids
Explanation:
Bacteria can acquire beneficial characteristics that they didn’t have. One way for these is through plasmids, which ones are little fragments of DNA that usually contains resistance genes (for antibiotics, disinfectants, heavy metals, etc.) or other capacities, like the ability to use some substances (for example sugars).
In this specific situation, we already know that the plasmid carrying genes for tetracycline resistance and the <em>lacZ</em> gene.
A little explanation:
Tetracycline is an antibiotic that inhibits bacterial growth and kills the bacteria. The bacteria can “fight” to this antibiotic if it has a resistant gene, the result is that the antibiotic can’t affect the bacteria and survive. An analogy is like a Police Officer (bacteria) that have a bulletproof vest (tetracycline-resistant gene) so the bullets (tetracycline) didn’t affect the police.
In the case of X-gal, is a compound consisting primarily in one sugar called galactose. Not all bacteria can eat galactose, they need an enzyme called β- galactosidase (comes from <em>lacZ</em> gene) that helps the bacteria “eat” the sugar (cuts the sugar in little pieces so the bacteria can eat).
Then, as the bacterial colonies can grow in the medium with tetracycline and X-gal, we know that those bacteria are carrying the resistance genes for tetracycline (does not affect the bacteria) and the <em>lacZ</em> gene (bacteria produce β- galactosidase that cuts galactose). These genes are coming from the plasmids because we already know that the plasmid carries these genes and not from the exogenous DNA.
Answer:
Natural selection
Explanation:
Microevolution refers to changes produced at a lower level than species. In genetics, microevolution is the change in the allelic frequency perceptible in a few generations. Most of these naturally produced changes by mutation, natural selection, genetic flux, genetic drift.
After the drought on Daphne Major, many of the plants producing small-sized seeds decreased their reproductive rate drastically. Consequently, there were almost no seeds available for the medium ground finch to feed. The population of this species also decreased to only a hundred birds over two years. Weather conditions and food availability influenced the survival of the animals.
With time, the finched population increased again, but now, the average size of the beaks was larger. The trait modification was related to the availability of only larger seeds with thick husks.
Eating large seeds with medium or small-sized beaks was impossible, so Finches needed to adapt, developing larger beaks to crack open the husks and eat the contents of the seeds.
<u>Natural selection was responsible for the rapid change in the finches´ population beaks size after the drought. </u>The evolutive force modifies the allelic frequencies, increasing the frequency of genetic variants that expressed the larger beak size and declining the frequency of the alleles that expressed smaller beak size.
