Tavi was running at a fast pace in a marathon. which of the following describes how the tavi's nervous system worked with his circulatory system to him to maintain homeostasis? a) the brain sends signals to the veins to decrease the blood pressure to the legs so that muscles have less mass b) the brain send signals to the blood vessels in the legs to dilate so that there is increased blood flow c) the heart send signals to the brain which then releases a hormone that causes the blood flow to decrease to the stomach d) the brain informed the heart to decrease its rate of pumping in order to slow the flow of blood during exercise

The correct answer is B) The brain send signals to the blood vessels in the legs to dilate so that there is increased blood flow.

During running Tavi's muscles need oxygen to break down fats and carbohydrates for energy. As we know that blood work as carrier for oxygen so to make room for fresh oxygen, the brain send signals to the blood vessels to dilate to increase the flow of blood in legs. The process of dilation of vessels in our body is called vasodilation.

a fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis.[1] the age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years.[2] fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas.[3] other commonly used derivatives include kerosene and propane. fossil fuels range from volatile materials with low carbon to hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. methane can be found in hydrocarbon fields either alone, associated with oil, or in the form of methane clathrates.

the theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the earth's crust over millions of years was first introduced by andreas libavius "in his 1597 alchemia [alchymia]" and later by mikhail lomonosov "as early as 1757 and certainly by 1763".[4] the first use of the term "fossil fuel" was by the german chemist caspar neumann, in english translation in 1759.[5]

in 2017 the world's primary energy sources consisted of petroleum (34%), coal (28%), natural gas (23%), amounting to an 85% share for fossil fuels in primary energy consumption in the world.[6] non-fossil sources in 2006 included nuclear (8.5%), hydroelectric (6.3%), and others (geothermal, solar, tidal, wind, wood, waste) amounting to 0.9%.[7] world energy consumption was growing at about 2.3% per year. in 2015 about 18% of worldwide consumption was from renewable sources.[8]

thrombocytopenia, which is a deficiency in blood platelets, can cause bleeding and bruising in the dermis similar to senile purpura. other possible causes include: exposure to ultraviolet rays and aging skin are common causes of senile purpura. senile purpura may also be a sign of collagen loss in the skin and bones.