Answer:
The correct answer is C) Passive transport
Explanation:
During the respiration process exchange of gases takes place between lungs and blood. This gas exchange is carried by simple diffusion which is a passive transport. Here gas molecule moves from area of higher concentration to the lower concentration area.
The lung's alveoli are surrounded by blood capillaries in which the concentration of CO2 is high while in alveoli concentration or partial pressure of CO2 is low so CO2 moves from blood to alveoli through diffusion.
In the case of oxygen, the concentration of oxygen is high in alveoli and less in blood inside blood capillaries so oxygen moves from alveoli to blood by diffusion. So the right answer is C.
Answer:
B
Explanation:
It's the same thing that Pavlov did with the dogs, but instead of a can opener, he used a bell. The dogs drooled at the sound of the bell because they knew that the food was coming.
Answer:
pre-zygotic reproductive isolation
Explanation:
<em>The molecules regulate the pre-zygotic reproductive isolation mechanism.</em>
<u>Reproductive isolation generally refers to the variety of biological processes that sustain the formation of new species of biological organisms. </u>
Some of these processes <em>act to prevent fertilization or the formation of zygotes between organisms that are not of the same species</em> (pre-zygotic mechanisms) while others <em>ensure that the product of fertilization is invalid</em> in case the former fails (post-zygotic mechanisms).
Some pre-zygotic mechanisms ensure that there exists no form of mating among organisms that are not of the same species due to incompatible reproductive organs, but where this fails, another pre-zygotic mechanism will act so that that the mating will not lead to fertilization and there will not be formation of zygotes.
The prevention of fertilization between organisms with compatible reproductive organs but of different species is carried out by molecules. These molecules ensure that there are locks and keys in place to prevent the fertilization of the egg by the sperm.
Answer:
12
12
24
Explanation:
<em><u>Musca</u></em> <u><em>domestica</em></u> is the scientific name of an animal popularly known as Housefly. From the question, it is known that this organism has a haploid chromosome number of 6.
In a diploid chromosomes, the number of chromatids that will be present will be twice of that in haploid.
Since haploid (n) = 6, diploid (2n) will be; 2 × 6 = 12
Somatic cells on the other hand also exhibit diploid number of chromosomes, again it means we will have (2n) = 2 × 6 = 12
In metaphase cell, cells do make sure they complete the S'phase of the cell cycle before cellular division.Therefore, the DNA present in the chromatids in the S'phase actively engage in chromatids doubling, as a result, 24 chromatids (i.e 12 × 2= 24) exists in the metaphase cell.
He created one of the first microscopes
