<span>The tracheae possibly have evolved directly from the book lungs</span>
Environments are always changing so organisms need to adapt to survive. The organisms that survive are the ones that are fit to live in that environment, which is where survival of the fittest comes into play.
Answer:deoxyribose
Explanation: From the information provided, (though the diagram is not shown), the structure is a DNA double helix. A DNA contains deoxyribose sugar thus the name deoxyribonucleic acid. RNAs contains ribose sugar thus the name ribonucleic acid. A deoxyribose is a pentose (a 5- carbon sugar) which lacks one oxygen atom at position two of its carbon skeleton, hence the name deoxy - ribose. It's usually written chemically as 2- deoxyribose.
The answer is C. Genetic drift is the change of an allelic frequency due to random sampling in a population. When the brown and black bottles are preyed upon compared to the green bettles, their numbers in a population decrease. Therefore the next generations/offsprings of bettles population is more likely to be of green beetles since they will be more in the parent population. The allelic frequency of the allele for green bettles becomes higher than that of brown and black beetles. Eventually, after generations, the black and brown beetles may be eliminated from the population
<span>The phase of mitosis during which the mitotic spindle begins to form is
PROPHASE.
</span>At prophase, the nuclear envelope is broken down; the chromosomes disperse into the cytoplasm, condenses and become visible;
and more importantly, the mitotic spindle fibers form.