Nucleus; Prokaryotic Cells do not have a nucleus, whereas Eukaryotic cells do
Answer:
Sometimes, molecules cannot move through the cell membrane on their own. These molecules need special transport proteins to help them move across the membrane, a process known as facilitative diffusion. ... Many channel proteins allow the diffusion of ions. Ions are charged atoms.
Explanation:
Answer:
Diatoms are mostly asexual members of the phytoplankton. Diatoms lack any organelles that might have the 9 + 2 pattern. They obtain their nutrition from functional chloroplasts, and each diatom is encased within two porous, glasslike valves. Which question would be most important for one interested in the day-to-day survival of individual diatoms?
C) How do diatoms with their glasslike valves keep from sinking into poorly lit waters?
Explanation:
Diatoms are some of the most important organisms living on earth because of its role on the oxygen production in the planet earth. The question "how do diatoms with their glasslike valves keep from sinking into poorly lit waters?" Because of the way their nutrition is obtained from functional chloroplasts and the way them encased within two porous, glasslike valves.
The four bases in DNA are adenine, cytosine, guanine, and thymine.
<span>These four are divided into two groups. The pyrimidines, the single-ring nitrogenous bases, is where thymine and cytosine is included. The purines, the double-ring nitrogenous bases, includes adenine and guanine. </span>
<span>Cytosine will only bond with guanine; they form three hydrogen bonds. Adenine will only bond with thymine forming two hydrogen bonds.
</span><span>Crossing over, independent assortment and fertilization are methods of genetic recombination. Genetic recombination is the production of offspring which possess combinations of traits that differ from those found in either of the parents. Crossover. This is the first way that genes are shuffled in sexual reproduction to produce genetic diversity. Chromosomes line up side by side and break off pieces of themselves, then trade those pieces with each other. Independent assortment. This is the process in which each homologous chromosome in a pair goes into a separate gamete, thus each gamete has only one copy of each gene and that gene may be a different version of the same gene that is in another gamete. Fertilization. External fertilization, common in organisms that live underwater such as fish and frogs, increases the number of eggs that sperm encounter. Not only does this result in a greater number of offspring, but it generates more genetic diversity. Internal fertilization e.g. in mice also has the advantage of producing four to eight pups after mating thus increasing diversity.</span>
