Explanation:
To swim, they move their tails up and down, rather than back and forth as fishes do. This is because whales evolved from walking land mammals whose backbones did not naturally bend side to side, but up and down. ... Whales do the same thing as they swim, showing their ancient terrestrial heritage.
Cetaceans are fully aquatic marine mammals belonging to the order Artiodactyla, and branched off from other artiodactyls around 50 mya (million years ago). Cetaceans are thought to have evolved during the Eocene or earlier, sharing a closest common ancestor with hippopotamuses.
The answer is operon. These set of genes are transcribed together because they share a single promoter and operator. Therefore they are transcribed into one mRNA and translated together. These genes are, therefore, expressed together at all times. Examples are the tryptophan and lac operons of Escherichia coli
Answer:
by Planting the Right Way
Explanation:
advise people to plant.
plant by yourself so people do the same.
Hi there!
<u>Electronegativity</u> is the concept of how likely an atom is to attract the shared molecules in one of these bonds to itself. We know the molecule water is made up of two hydrogens and one oxygen. The electronegativity of hydrogen is 2.2, and oxygen 3.4. An <u>ionic bond</u> needs at least a difference in electronegativity of 1.6. As the difference is less than that, we can say that water is a covalent molecule. This then wipes out choice B, because it is not ionic, and C, as we have seen it is actually covalent.
Now, we can see the difference in electronegativity between oxygen and hydrogen is still 1.2. This means that while it is not at the point for there to be an ionic bond, there is still a difference in attraction, where the electrons will tend to favor the oxygen more and 'hang around it' more. As electrons are <u>negatively charged</u><em><u>,</u></em> this means that the oxygen will gain a slightly negative charge. This then makes the molecule polar, because it now has a charge within the molecule. This means we have our answer, choice D.
In terms of hydrophobic molecules - they tend to be ones without a charge. (If you're interested in this kind of stuff, I'd search hydrophobic up, and possibly also look into hydrogen bonds).
Hope this helps! Feel free to ask me any other questions you have about this specific problem.
Answer:
Chemical
Explanation:
An apple has energy stored within fructose and glucose inside of it, which is a form of chemical energy. A typical apple has about 90 kilo calories of energy inside of it, which is enough to raise the temperature of 90 liters of water by 1 degree Celsius. Hope this helps!
