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What causes objects to float or sink?

People are often confused how a chunk of steel, which sinks if thrown into water, can be formed into a ship that floats. The answer lies in the shape of the object. By forming a bowl shape from the steel, it causes more displacement of water as the air portion of the bowl also takes up space and displaces water. More water displaced equals more force acting against the object and results in heavy objects being able to float on water.\nAnother quality that affects an object’s ability to float is its density. Density is how heavy an object is compared to its volume. A piece of cork floats rega..

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What is the function of the corneal reflex?

Also known as the blink reflex, the corneal reflex occurs when the eye is touched by a finger, a cotton swab or even by bright light. It is a quick reflex, occurring in approximately 0.1 second in healthy patients. People who wear contact lenses may show a diminished blink reflex, since they have adapted to touching the surfaces of their eyes.\nPhysicians often evaluate the corneal reflex when neurological damage is suspected. When a patient is in a coma, a physician can attempt to stimulate the corneal reflex in order to determine whether the cranial nerves have been damaged. In healthy patie..

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What is the difference between ester and ether?

Typically, ester is a derivative of carboxylic acids and alcohol, while ether is considered an organic compound. Esters are naturally occurring in most foods, especially fruits, and emit various scents that are commonly used in fragrances, pheromones and essential oils. Esters also originate from natural oils and fats.\nEthers are less polar than esters. Due to their volatility, esters can be identified using a laboratory procedure called gas chromatography. Ethers are very stable compounds and have relatively low chemical reactivity. This stability is due to an ether's inability to react..

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What phase of the bryophyte life cycle is dominant?

Plants such as mosses, liverworts and hornworts are bryophytes. Bryophytes make their own food through the process of photosynthesis with the exception of one particular liverwort called cryptothallus, which depends on the ectomycorrhizal fungi for food. Bryophytes thrive in less polluted areas and commonly grow on substrates such as tree trunks, rotting wood, rock and soil.\nBryophytes do not have true roots; instead, they have root-like protuberances called rhizoids that do not take out water and minerals from the substrate. To reproduce, bryphotes require a damp environment.

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What are examples of motile organisms?

The distinction between motility and its opposite, sessility, is more important in creatures such as bacteria, as many species cannot move on their own.\nOne species of motile bacteria is Rhodospirillum rubrum. This creature is photosynthetic, like plants, but it can move about with a spiralling motion using a thread-like structure that wraps around the whole cell, called an axial filament.\nCnidarians, a group of soft-bodied animals that live in the sea, also have many species that are motile and many that are sessile. An example of a motile cnidrian is the lion's mane jellyfish.

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What are the effects of water pollution on plants?

Nutrient pollution often occurs because of many human activities, including runoff from farmland. Rain dissolves phosphorous and nitrogen from fertilizers applied to crops and animal waste. The increase in nutrients leads to a potential algae bloom that causes dead spots in the water due to oxygen depletion.\nAcid rain is another form of water pollution affecting plant life. Acid rain occurs when water in the atmosphere dissolves chemicals, including sulfur dioxide and nitrogen dioxide, formed by volcanoes and automobile engines. As the precipitation falls to the ground, it pollutes water supp..

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When does daylight savings time typically start?

Other countries that observe DST in the Northern Hemisphere besides the United States can set clocks ahead some time during the months of March and April, and then clocks go back to standard time between the months of September and November. In the Southern Hemisphere, DST occurs in the reverse order, where clocks are set ahead some time during the months of September and November.The reason for using daylight savings time is that it provides extra hours of natural daylight. Benjamin Franklin is credited with the concept of daylight savings time.

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What are the advantages and disadvantages of adding fluoride to drinking water?

Regular use of fluoride can drastically reduce the number of cavities a person develops in teeth. Thus, drinking public water that is treated with fluoride minimizes decay. Not only is direct contact of the tooth surface beneficial, but fluoride also provides ongoing oral care benefits when one generates saliva with fluoride already in the system. The benefits of fluoride-treated water are especially important to low-income families who cannot afford regular dental care. Elderly people may also enjoy extended benefits for their natural teeth by regularly drinking water with fluoride, according..

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How does sugar affect the boiling point of water?

The formula for calculating the effect of sugar and other non-ionizing solutes on the boiling point of water is linear, which means that every additional gram has the same effect on the boiling point of a liter of water. Ionizing solutes, such as salt, impact the boiling point of water much more significantly; in the case of salt, that same gram elevates the boiling point of a liter of water by 1.87 degrees Fahrenheit.

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Where is acid rain found?

Acid rain is described as any kind of wet deposition of acid (nitric and sulfuric) in the form of precipitation, such as rain, snow or fog. Rain is called acidic when it falls with a pH rate of less than 5.0. Acid rain can occur anywhere the release rates of burning fossil fuels, sulfur dioxide (SO2) and nitrogen oxides (NOx) are very high.

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