Answer:
Blood clothing is an example of positive feedback.
This type of feedback mechanism is useful to the body because it multiplies the factor that intervenes in clotting accelerating the process.
If a toxin affects the molecules that signal for platelets the feedback will not be effective enough to produce clotting and the body will keep bleeding.
Explanation:
Blood clotting is an example of positive feedback due to the fact that when the vascular endothelium is damaged platelets will go to this area and activate themselves once they are in contact with the collagen fibers of the damaged structure. When the platelets are activated they will release the contents that is stored in their granules. One of the contents is a Gq-linked protein receptor cascade, that will increase the concentration of calcium in the platelets. Calcium activates protein kinase C, which, in turn, activates phospholipase A2 (PLA2). PLA2 will modifies an integrin membrane increasing its affinity to bind fibrinogen. The activated platelets change their shape , and the fibrinogen cross-links with the integrin membrane aiding in the aggregation of adjacent platelets. After this the coagulation cascade takes place. there are two pathways the extrinsic and the extrinsic one.
The extrinsic pathway will be activated due to tissular factor released by the platelets and the intrinsic pathway will be activated due to endothelial collagen. The final product of both pathways is factor x.
Factor x will transform prothrombin into thrombin will activate the conversion of fibrinogen into fibrin. Thrombin will form a net of fibrin that will the clot.
A cascade reaction is useful because every component of the cascade are related making a quick reaction once that one of then is activated and can activate other or more factors.
If a toxin affects the molecules that signals for platelets, platelets will not go to the damaged area and in consequence there will not be thrombin and fibrin to form the clot together with platelets.
High power if your using a light microscope. Hope this helps.
Principle of Dominance was given by Sir Gregor Johann Mendel.
<h3><u>Explanation:</u></h3>
Principle of Dominance was given by Sir Gregor Johann Mendel as a conclusion of the monohybrid cross between the different characteristic pea plants. It says that in an organism which is heterozygous for a particular character, only the dominant trait is able to express as a phenotype, not the recessive one. In other words, the recessive allele is completely masked by the presence of the dominant allele. This leads to same phenotype of a homozygous dominant organism and a heterozygous organism.
To test the organism about its heterozygosity, the organism is led through a test cross where the organism is crossed with a recessive organism. If the F1 offsprings are all dominant, then the organism is homozygous dominant, and if the F1 offsprings are of half dominant and half recessive phenotype, then the organism is heterozygous.
Answer:
Dietary fats are essential to give your body energy and to support cell growth. They also help protect your organs and help keep your body warm. Fats help your body absorb some nutrients and produce important hormones, too. Your body definitely needs fat.
Explanation:
I believe the answer would be B
