In eukaryotes, the DNA strands are linear, and DNA polymerase can't replicate the very ends of the DNA strands! These ends are "protected" by repeated sequences called "telomeres." Either the chromosome gets shorter with each replication, or else a special enzyme-nucleic acid complex called telomerase adds new telomeres to the ends. A prokaryotic chromosome is circular and thus does not have the problem of having ended.
<span>Eukaryotic DNA is wound around histones, coiled, and supercoiled -- to replicate it, there have to be unwinding mechanisms, and mechanisms to reduce the degree of coiling. In prokaryotes, the winding problem is much less, and there aren't any histones.</span>
Answer: Pacific Northwest Animals & Birds
- Spotted and snowy owls.
- Bald and Golden eagles.
- Pileated woodpecker.
- Rufous hummingbird.
- Great Blue Heron and Canada goose.
- Seabirds, including cormorant.
- Bear.
- Olympic marmot.
Kitsap Peninsula:
Marine mammals of the sound include orcas, sea lions, sea otters, gray whales, humpback whales, and harbor seals. Underwater plants provide food, breeding areas, nurseries, and resting places for wildlife in the sound.
Answer:
The two main reasons are nonpolar core of the bilayer and the active transport.
Explanation:
The membrane is structured to have two outer layers that are polar and an inner layer that is nonpolar.
If a membrane protein is exposed to the solvent, i<em>t will also have a polar side. It would be very difficult for the polar face of the membrane to move through the nonpolar core of the bilayer.</em> Therefore, this model is not feasible.
One major form of transport, active transport, moves solutes up the concentration gradient. <em>The binding of a solute and then release on another side of the membrane would only work for facilitated diffusion because it would cause a net movement of solutes down the concentration gradient.</em> It is unclear how energy could be expended to drive this process in the transverse carrier model.<em> Therefore, the transverse carrier model does not explain active transport.</em>
Answer:
Explanation:
Placoderms were the first jawed fish; their jaws likely evolved from the first of their gill arches. in spanish
placodermos
<span>Histidine is what it would produce.</span>
