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What are some facts about winter for kids?

In the winter, the December solstice occurs when the Earth tilts on its axis at negative 23.5 degrees. It is considered the shortest day of the year. In the United States, there are only about 9.5 hours of daylight during the winter solstice. The Arctic Circle around the North Pole is in total darkness during this day.\nAnother fact that kids may find interesting is that snow comes in different crystal shapes. Often depicted as stellar dentrites, snow can fall in a variety of shapes, such as simple prisms, hollow columns, fernlike stellar dentrites and triangular crystals. The shape of the sno..

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What is a micromolar?

There are over 6 trillion atoms in a micromolar, which makes it impractical to measure them in terms of individual atoms. However, single micromolar-sized samples are often also quite small in terms of mass and size, so it is also difficult to measure them in terms of grams. Micromolars allow for a more simple expression of molecular density when studying chemical composition and reactions.

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Has any human ever been to Mars?

Humans first visited space in the 1960s, with the United States and the former Soviet Union both sending astronauts to orbit the earth. Manned space exploration peaked in 1969 when Americans Neil Armstrong and Buzz Aldrin landed on the moon. Numerous satellites have photographed Mars, and the United States in 1976 landed two probes, Viking 1 and Viking 2, and two rovers, Spirit and Opportunity, on the Martian surface in 2004. This has been the extent of human interaction with the Red Planet. However, the scientific community is diligently working on a mission to send man to Mars.

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What color is Neptune?

Neptune's atmosphere contains bright cirrus-like clouds that change regularly. Neptune also has six rings that are made up of clumps of dust called arcs. Neptune is a very cold planet due to its distance from the Sun, which is 2.8 billion miles.

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What are the five agents of erosion?

As the wind picks up particles, they brush across rocks or compacted earth, causing more particles to break away. Water erosion takes place when the water in a stream carries pieces of the shore with the current. When an ice glacier moves down its bed, bit of the earth become embedded in it and are carried along. Waves crashing along the shore pound and grind rock and dirt into tiny particles that are moved as the waves recede. Gravity pulls any loose bits down the side of a hill or mountain.

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What factors affect cell membrane permeability?

Cell membranes are selectively permeable, allowing some substances to pass through while restricting the passage of others, says Physiology Web. This is essential for providing a cell with nutrients, eliminating waste and preventing unwanted molecules from entering a cell. The double phospholipid layers of a cell membrane include polar heads and non-polar tails, says WiseGeek. Cell membranes are very permeable to non-polar molecules, such as oxygen, nitrogen, carbon dioxide and steroids, says Physiology Web. Conversely, membranes are less permeable to small polar molecules, such as water, glyc..

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What is the preparation of cyclohexanol from cyclohexene?

The process is done in two parts. The first part begins by preparing the alkene by dehydrating the alcohol. Afterwards, the alkene is subjected to robust oxidation conditions to create a dicarboxylic acid.\nFor the dehydration process to work, the original product has to be contaminated with water, not-yet-reacted alcohol (the cyclohexanol) and phosphoric acid. Once the process is complete, dicyclohexyl is present as a side product and must be removed in the first distillate. A second distillation needs to be completed to ensure that all of the dicyclohexyl is removed. The success of the overa..

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What is the structural formula for carbon dioxide?

Carbon dioxide compounds exist in a linear, symmetrical form with the carbon molecule in the middle and an oxygen molecule covalently bound on each side of the carbon. The oxygen and carbon molecules share double bonds and have a bond length of 116.3 picometers. It is considered a linear molecule due to its hybridized carbon molecule and its symmetrical carbon-oxygen double bonds.

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What do nucleosomes do?

Nuclesomes perform a paradoxical task, protecting DNA from damage and contamination while allowing polymerase to transcribe messenger RNA and replicate the DNA when the cell divides. Scientists do not completely understand how nucleosomes manage to remain stable and labile at the same time, according to the Research Collaboratory for Structural Bioinformatics. Research suggests that the nucleosome may partially unwind in the reading process, allowing proteins to read genetic information one loop at a time.\nScientists understand the role nucleosomes play in gene expression better than the acce..

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How do living and nonliving things interact in the environment?

In addition, living organisms in an environment without sufficient non-living resources may have trouble getting what they need for survival due to competition for those resources.Some examples on interactions between non-living and living things include plants getting their minerals from the soil and making food using sunlight, animals needing a specific temperature range for their body processes to function properly and sea creatures needing either saltwater or freshwater.

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