Answer:
Most restriction enzymes recognize sequences of 20-25 bp in length
Explanation:
Sequences of DNA that are recognized by restriction enzymes are called recognition (or restriction) sites are usually are between 4 and 8 bases long. Many of them are palindromic, which means that they are the same when you read it backwards and forwards (mirror-like).
Restriction enzymes are endonucleases, which means they cut phosphodiiester bonds within DNA. These enzymes are from prokaryotic organisms (archea and bacteria) which use them as defending mechanism against viruses. Prokaryotes protect their own DNA via methylation, performed by methyltransferase.
Answer:
- In terrestrial environments: increasing CO2 levels cause an increased photosynthetic rate
- In aquatic environments: increasing CO2 levels cause an increase in water acidity
- In both terrestrial and aquatic environments: increasing CO2 levels lead to an overall increase in the average temperature (global warming)
Explanation:
In terrestrial ecosystems, rising carbon dioxide (CO2) levels increase the rate of photosynthesis (since CO2 is one of the reactants in photosynthesis), thereby also increasing plant growth. Moreover, in aquatic ecosystems, rising CO2 concentrations increase the levels of this gas dissolved on the surface of the oceans. This increases the acidity of the oceans, thereby modifying habitats and food web structures. The increasing acidity of the oceans also reduces the amounts of carbonate, which difficult for aquatic species (e.g., corals) to form their shells/skeletons. Finally, CO2 is a greenhouse gas that contributes to the increase in the average temperature by absorbing solar radiation that would otherwise have been reflected by the Earth's surface, and this increase in the temperature negatively affects life in both terrestrial and aquatic environments.
Covalent bonds are formed when two atoms are able to <em>share</em> electrons.
Iroinic bonds are form when two atoms are <em> </em> electrons from each other to complete the bond. This results in a pair of ions.
<u>Covalent bonds:</u>
- Have a definite shape.
- Have a low melting point.
- At room temperature they are in a liquid or gas.
- They occur between two non-metals.
<u>Ionic bonds:</u>
- Have no definite shape.
- Have a high melting point.
- At room temperature they are solid.
- They occur between a metal and a nonmetal.
These are sensor, registry and short-term memory.
Answer:
Nucleus, Chromosomes, Bases, gene
Explanation:
