Answer:
Flatworms are beings that do not have a heart, veins, arteries, capillaries, hemolymph, or some type of circulatory fluid. Their circulation occurs between cells or intercellularly and they are responsible for transporting substances by diffusion from cell to cell.
Explanation:
Flatworms are considered multicellular eukaryotic organisms. This implies that in their cells they have a cellular nucleus, in which the DNA is contained, structuring the chromosomes. Likewise, they are made up of several types of cells, each one specialized in a specific function. They lack a structured circulatory system as such. Because of this they do not have specialized structures such as a heart or blood vessels, however, the circulation of certain substances is established between their cells. This is done thanks to the diffusion process. Substances pass from one cell to another through this process.This does not apply to all flatworms, since in some species of bog and digenae there is a certain organization and some very small conducting vessels known as the endolymphatic system, the which forms a kind of plexus in the parenchyma.It should also be noted that some species do not even have a digestive system, being the digestive tract the one in charge of digestive functions and the distribution of the nutrients they receive.
Explanation:
The influence from radioactivity is inversely proportional to the number of chromosomes , since , humans have more DNA , chromosomes than the insects , and therefore , due to less chromosomes in insects , they are more resistant towards radioactivity .
As the target of the radiation is the DNA .
Hence , It is clear that insect due to lesser DNA are less prone to Radiations .
The answer regarding the components of an arthropod's nervous system would be item C. It consists of brain, nerve chord, and ganglia. The brain is located dorsally, while the nerve cord together with the ganglia is ventrally structured — extending on each segment of an arthropod’s body.
<span>An ecosystem consists of a population of organisms and its
physical environment, and a population is made up of many different
communities of organisms. Every one of the creatures of similar species
living together that live in a particular biological system are known
as a populace The people in the populace contend with one another for
sustenance, settling space, and mates.</span>
Answer:
of the low pH of the vagina.
Explanation:
The pH of the vagina is maintained at highly acidic levels to prevent the germ buildup. The range of vaginal pH is around 3.8 to 4.5. The very low pH of the vagina creates a hostile environment for sperms and most of the sperms are killed as they enter the vagina due to the acidic pH.
Apart from supplementing the sperms with energy, cervical mucus serves to protect the sperms from the hostile conditions of the vagina. The cervical mucus has an alkaline pH at or near the ovulation to protect sperms from acidic pH of the vagina and to facilitate fertilization.
