What is the function of nervous tissue for transport within an organism?

PLEASE HELP IM DESPERATE

Furkat [3]

Answer:

8. D

9. A

10. A

11. C

12. D

Explanation:

8. Natural selection works on variation that exists in the genes of organisms. Antelopes who have genetic variation that makes their legs more muscular are at an advantage because they can outrun predators. This increases the chance that they will reach reproductive age, and be able to pass this advantageous trait onto their offspring. Over time, this selection pressure makes the variant more common in a population.

9. Beneficial traits are those that give a selective advantage. This could be one that helps it outrun predators (like above), avoid illness and death, gives it a reproductive advantage (i.e. more attractive to mates), or makes it better able to digest certain foods, for example. The formation of cancer cells would be harmful for an organism, reducing its fitness and perhaps leading to death. The inability to reproduce would mean genetic info is not passed on to the next generation, and stopping the production of an essential protein would likely lead to death. However, resistance to a virus would help an organism avoid illness and death, improving fitness.

10. Genotypes are what organisms inherit from their parents, i.e. the genetic information that is passed on. However, the way in which different alleles interact and are expressed is the phenotype. If we take the above example, natural selection is acting on the phenotype of muscular legs. If an antelope had the muscular leg genotype but for some reason it was not being expressed (maybe another gene is interfering with it), then the antelope would not have a selective advantage, and natural selection could not be act on the trait.

11. A trait that better suits an organism to its environment will be selected for by natural selection. This is because that organism is more likely to survive due to the trait, giving it a selective advantage. Therefore, if a mutation arose making the giraffe more adapted to the environment, it would be positively selected for, and through evolution would become more common.

12. This is an example of selective breeding, which has been happening for generations. Farmers spot desirable traits, and cross horses with these traits in an attempt to enhance the trait or to ensure it is passed on to the next generation. This is not natural selection, because farmers are making it happen artificially. It is not cloning or recombinant DNA, which are terms scientists use for actually manipulating the DNA in the lab.

3 0

3 years ago

Which statement regarding hemodialysis is true?

SOVA2 [1]

Answer: B. The blood is circulated out of the body for cleansing and then returned.

Explanation:

Hemodialysis is a medical therapy in which the patient's blood is taken out with the help of tubes and treated out of the body. The blood is pumped out using the blood compartment. The blood is circulated using a external filter, that is called as dialyzer. The blood get cleansed and impurities are removed and purified blood returned via circuit back to the body. This technique is used to control the blood pressure and balance of important minerals in the body that involves the potassium, sodium and calcium in the blood.

Based on the above information, option. B is the correct option.

8 0

3 years ago

Classify the following characteristics depending on if they describe events occurring in mitosis, meiosis I, or meiosis II.

Temka [501]

Answer:

Mitosis events are:

Results in 2 genetically identical

diploid nuclei

A diploid number of sister

chromatids align at the spindle

equator during metaphase

Meiosis I events are:

Results in 2 genetically diverse

haploid nuclei

Homologous chromosomes align

at the spindle equator during

metaphase

Homologous chromosomes pair

up during prophase

Crossing-over occurs during

synapsis

Meiosis II events are:

Results in 4 genetically diverse

haploid nuclei

A haploid number of homologous

chromosomes align at the spindle

equator during metaphase

Explanation:

Mitosis is a type of cell division which produces two daughter cells that are genetically identical to the parent cell. In mitosis, the chromosome number of the parent cell is maintained in the daughter cells i.e. a diploid cell (2n) will undergo mitosis to produce two diploid (2n) daughter cells. During mitotic division, sister chromatids (replicated chromosomes) are involved in the division stages. i.e. diploid sister chromatids align at the equator of the cell during Metaphase and also sister chromatids are separated or pulled apart to opposite poles during Anaphase.

Meiosis, on the other hand, is a kind of cell division that results in daughter cells with a reduced number of chromosome (by half). Since the chromosome number is reduced, meiosis occurs in a two step division process viz: Meiosis I and II.

Meiosis I produces two genetically different daughter cells. The daughter cells have a reduced number of chromosomes i.e. from diploid (2n) to haploid (n). Meiosis I involves homologous chromosomes (similar but non-identical chromosomes received from each parent) which pair up to form a TETRAD structure in the Prophase stage. This structure allows for an exchange of chromosomal segment between non-sister chromatids of homologous chromosomes, a process called CROSSING-OVER. Crossing-over is what makes the daughter cells genetically different from the parent cell. Homologous chromosomes also aligns at the equator of the cell during Metaphase and later separates during Anaphase.

Meiosis II divides the two daughter cells produced in meiosis I into four genetically different daughter cells. Since the chromosome number has been reduced from diploid (2n) to haploid (n) in meiosis I when homologous chromosomes separate, haploid sister chromatids are involved in the stages of meiosis II i.e. haploid sister chromatids align at the equator of the cell during Metaphase and eventually becomes pulled apart during Anaphase.

5 0

3 years ago

After cell division each daughter cell has

Genrish500 [490]

Cell division is the process by which a cell divides into two daughter cells and as a cell becomes larger, its volume increases faster than its surface area. The answer is b. a higher surface area/volume ratio than the parent cell. <span>
</span>

8 0

3 years ago

Read 2 more answers

Which lab equipment tool would you use to measure exactly 4 ml of water? explain your reasoning

inysia [295]

A Beaker is a laboratory tool used to measure exact measurements of water

5 0

3 years ago

Read 2 more answers