38. Mitosis and meiosis are the two different ways cells divide. They both share common characteristics and processes, but differ in some very important ways.
I answered part A and B of this, but I need help with C:
c. Why is it important for chromosomal exchange to occur during meiosis and not mitosis?
Also:
2. Which statement best explains the effect of resources on population size?
a. The exponential growth curve models the effect of limiting resources on population size.
b. Limited resources decrease the growth rate of population size
c. Density-dependent factors invariably lead to a positive DN
d. all of the above
Need help with this as well.
Thanks!
-MC
The purpose of meiosis is to form gametes, and ultimately offspring; therefore, "crossing over" is advantageous because it increases genetic variation. Mitosis, however, is necessary to grow bigger and repair damaged tissues. If you had chromosomal exchange during mitosis, then the daughter cell would not be the same as the parent cell.
The effect of limited resources is to decrease the growth rate. No food, no offspring.
Thanks so much!
-MC
Ok your first question,
In mitosis you end up with two cells, each of which has exactly the same chromosomes as the original cell. In meiosis, you end up with 4 cells, each of which has half as many chromosomes as the original cell. In many organisms, the for cells formed by meiosis are the gametes that are used in sexual reproduction.
In meiosis, there are basically 2 consecutive rounds of division. The details of the chromosome separation are different for the first and second division of meiosis.
Chromosome exchange (recombination) happens in meiosis, but not in mitosis.
Chromosomal exchange insures that every gamete that is formed has a different combination of genes. That makes every offspring from matings of two individuals be genetically unique. In mitosis, you want to make sure that every cell formed is genetically identical to every other cell.
The second question has to be Dbecause I know a and b are right and im pretty sure c is right as well.
describe the ecosystem's population growth and regulation through community interaction
To answer your first question about why chromosomal exchange occurs during meiosis and not mitosis, it's important to understand the differences between these two processes.
Mitosis is a cell division process that leads to the production of two identical daughter cells, each with the same number and type of chromosomes as the parent cell. It is involved in various functions such as growth, tissue repair, and asexual reproduction. During mitosis, there is no exchange of genetic material between chromosomes.
On the other hand, meiosis is a specialized cell division process that occurs in the production of gametes (sperm and eggs). It involves two rounds of division, resulting in four non-identical daughter cells, each with half the number of chromosomes as the parent cell. One of the key events in meiosis is the exchange of genetic material between chromosomes, also known as chromosomal recombination or crossing over.
Now, let's get to the importance of chromosomal exchange during meiosis. The primary reason for chromosomal exchange is to introduce genetic diversity. By swapping sections of DNA between homologous chromosomes, meiosis generates new combinations of genetic information. This genetic variation is crucial for the survival and evolution of species.
During meiosis, crossing over promotes independent assortment of alleles (different versions of a gene) and shuffles the genetic material from both parents. This leads to the generation of unique combinations of traits in offspring. In contrast, mitosis does not involve recombination and only produces identical copies of the original cell.
Moving on to your second question, the statement that best explains the effect of resources on population size is:
b. Limited resources decrease the growth rate of population size.
Limited resources, such as food, water, and shelter, act as a restraint on population growth. When resources are scarce, individuals within a population compete for these resources. This competition can lead to reduced growth rates, increased mortality, and lower reproductive success. As a result, the population size may stabilize or even decline due to the limited availability of resources.
The other options in the question do not accurately explain the effect of resources on population size. The exponential growth curve referred to in option a is used to describe the population growth in the absence of resource limitations. Density-dependent factors mentioned in option c refer to factors that influence population growth, usually related to population density, but they do not always lead to positive population growth. Option d, "all of the above," is not correct because not all the statements accurately explain the effect of resources on population size.
I hope this helps! Let me know if you have any more questions.