The Richter scale is a way of giving the intensity of all earthquakes a numerical value. this allows the strengths of different earthquakes to be compared. Because of this, i think the best answer is D
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.
Answer:
The respiratory system is necessary for an organism's body to live because it introduces oxygen-rich air, which is needed to perform vital functions, while at the same time promoting the elimination of carbon dioxide.
Explanation:
Oxygen (O₂) is necessary for life because it participates in the process of cellular respiration, a mechanism that allows the oxidation of glucose to form energy in the form of ATP.
The respiratory system is made up of a set of organs that carry air into the body and facilitate gas exchange, i.e. the entry of O₂ into the blood and the elimination of potentially harmful carbon dioxide (CO₂).
This exchange of gases occurs in structures called pulmonary alveoli, whose surface is located in relation to the pulmonary capillary vessels.
- The entry of air into the lungs brings O₂ to the alveoli, which will diffuse into the pulmonary capillary for the process of hematosis or oxygenation of the blood.
- CO₂, a product of metabolism, leaves the capillary to the alveoli, to join the air that will be expelled during expiration.
Both O₂ and CO₂ require a transport molecule in the blood, red blood cell hemoglobin, which binds the gases and allows them to be transported to and from the tissues.
Learn more:
Exchange of respiratory gases brainly.com/question/4569375
A- the ratio to surface area
The oceans, lower atmosphere, and continents are parts of the biosphere.
The biosphere is composed of the parts of planet Earth where life exists and it is the total of all the ecosystems. The biosphere along with lithosphere (rock), hydrosphere (water) and atmosphere (air) are the four layers that surround the earth. The biosphere covers a wide area from the deepest root systems of trees, to rainforest, to the ocean depth and high mountaintops. The biosphere contains living organisms and nonliving things from which they obtain energy and nutrients.