Answer:
<em>The overuse of pesticides</em>
Explanation:
Pesticides are usually sprayed on plants so that the pest organisms can be killed. But these chemicals sprayed on plants can be toxic for humans when humans consume crops which have been sprayed with pesticides. Also, erosion causes these toxic chemicals to get eroded in the nearby lakes. The chemicals in the pesticides are harmful for every life that uses this water. Hence, the overuse of pesticides might kill pests but it is also toxic for consumption by humans.
Consumers/producers: A surplus of consumers and a reduced amount of producers cause an ecosystem to collapse. Their are more mouths to feed then there is food
Answer;
-Structural isomers.
Explanation;
-Isomers are molecules that have the same molecular formula, but have a different arrangement of the atoms in space.
-Structural Isomers are molecules which have the same molecular formula but have different connectivities. That is; the molecules have the same molecular formula, but their atoms have different arrangements or bonds.
-For example, butane and isobutane are structural isomers, also called chain isomers. In chain isomers, the carbon atoms are connected in different orders. Isobutane and butane have a molecular formula of C4H10.
B. mitochondria and nucleus
Answer: DNA is a molecule made up of two strands, twisted around each other in a double helix shape. The two strands are complementary which have a 5 prime end and a 3 prime end. To understand this question you must first understand the steps that follow.
DNA Replication:
<u>Step one: </u>
DNA Helicase (unzips) separates the strands.
<u>Step two:</u>
DNA Primase starts the process and makes a small piece of RNA called a primer. This marks the starting point for the DNA.
<u>Step three:</u>
DNA Polymerase binds to the primer and will make the new strand of DNA. DNA Polymerase can only add DNA bases in one direction, from the 5 prime end to the 3 prime end.
- The leading strand is made continuously.
- The lagging strand does not run continuously because it runs in the opposite direction. Each fragment is started with an RNA primer. DNA Polymerase then adds a short row of DNA bases from the 5 prime to 3 prime direction. This results in okazaki fragments because it can only replicate in small chunks. The process is repeated.
<u>Step four:</u>
Once the new DNA is complete the enzyme exonuclease removes all the RNA primers from both strands of DNA.
<u>Step five:</u>
Another DNA Polymerase fills in the gaps that are left behind with DNA.
<u>Step six:</u>
DNA Ligase seals up the fragments in DNA, in both strands to make a continuous double strand.
<u>Final answer:</u>
DNA Replication cannot replicate at the same time due to the leading and lagging strand.
Good luck!
