Renal autoregulation is the ability of the kidneys to maintain a relatively constant GFR or glomerulofiltration rate despite fluctuating blood pressure. Autoregulation is a remarkable property of multiunit smooth muscles of small arteries and arterioles to respond to changes in internal and external pressure. The blood vessels in the human body react by contracting whenever the blood pressure is elevated and by expanding when the blood pressure is reduced. On the other hand, if there is an elevation or reduction of the external interstitial pressure, it results in dilation and contraction, respectively. The lowest autoregulating pressure is about 60 mmHg. By a further reduction in perfusion pressure, RBF is sharply reduced.
A model is a way of describing natural phenomenon that scientists uses to make various prediction.
Explanation:
A model is said to be good if it is both accurate as well as easy to understand which makes powerful as well as simple. Most of the models have certain approximation those are necessary for describing a model. As the observations are not exact so there may be little difference between what we observe. Models which are simple increase the accuracy and becomes superior in nature as well.
There are certain limitation of model such as , most of the model cannot explain the complex natural phenomena. For example when we want to measure distance it becomes difficult ,in the model we can represent earth as a sphere but it is difficult to show variation in distance as there are valleys mountain ranges and other features.
Where is the question bro?
1. I believe the answer is the nucleus. Nucleus is a part of cell in living organisms that stores genetic materials. It is believed that the eukaryotic nucleus could have evolved from the fusion of thermoacidophil archebacterium fused with a motile eubacterium. This is a defining feature of eukaryotic cells. There is evidence that nuclear pore complexes and nuclear membranes co-evolved with the endomembrane system, and the last eukaryotic common ancestor had fully functional nuclear pore complexes.
2. Recombinant DNA technology involves altering genetic material outside an organism to obtain enhanced and desired characteristics in living organisms or as their products. It involves insertion of DNA fragments from a variety of sources, having desirable gene sequence via appropriate vector. However, the government has still not approved the technology in genetically modified grass because of the concern of the release of genetically engineered organisms into the environment and the concerns about environment safety.
3. Meiosis is the process of cell division which takes place in the gametes cells where the a diploid (2n) parent cells divides into four haploid cells. The process takes place in two stages namely meiosis I and meiosis II. At the end of meiosis II the daughter cells formed are haploid (n) meaning they have one set of chromosomes as compared with the parent cell. This means the four daughter cells have half as much and genetically the same as the original parent cell.
4. Speciation is the process by which new species are formed from a population. This process takes place as a result of geographic, anatomical, physiological or behavioral factors that prevent previously interbreeding populations from breeding with each other. Thus, in this case, i would say that speciation has definitely occurred when two groups of related organisms become permanently isolated from each other.