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What is a heterogeneous liver?

A heterogeneous liver can be caused by fatty liver disease, tumors or cirrhosis. CT scans can detect the additional fatty structures in the liver, which appear on the scan as areas of lighter-colored tissue, according to an article in The Oncologist. Fatty liver is a reversible condition that can be brought on by bad diet or high alcohol consumption. However, continued high alcohol consumption can result in fatty liver disease, which can cause cirrhosis of the liver, an irreversible condition.\nTumors can range from benign liver tumors to cancerous masses and metastases from cancer elsewhere i..

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What is the structure of a spirogyra cell?

The feature for which the genus is named is the spiral chain of chloroplasts that almost fills each cell. The chloroplasts wind themselves around the central vacuole in which the cell nucleus is suspended by cytoplasmic strands. The vacuole is filled with water and keeps the cell inflated, so the chloroplasts have more surface area for light absorption.\nSpirogyra are considered unicellular plants even though they typically are found in long, free-floating filaments. This is because although the cells group themselves together, there is no communication or transport between the cells, as there..

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What was Millikan's contribution to atomic theory?

Millikan's oil-drop experiment involved spraying oil from a perfume atomizer into a sample chamber. Some of the droplets traveled through a pinhole into a space between two plates, one of which had a negative electric charge and the other of which had a positive charge. This central chamber was then ionized with X-rays. Particles that failed to catch electrons followed gravity to the bottom plate, while particles that managed to catch at least one electron floated up to the positive plate or fell at a slower rate of speed. Millikan reached the conclusion that each drop had a charge that w..

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What was one of the incorrect postulates of Dalton?

Dalton's theory also stated that atoms combined to form compounds in a ratio of simple whole numbers. This was shown to be incorrect in light of the ratio of atoms in complex organic compounds, such as sucrose, or table sugar, with the molecular formula of C12H22O11. Dalton's atomic theory did, however, correctly recognize the fundamental difference between an atom and a molecule. His work also helped to explain the laws involved when chemicals combine.

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Why is the sun called the sun?

The ancient Greeks called the sun Helios, which was also the name of their god of the sun. The Greek name is still used in words such as heliotropic and heliocentric, but the more commonly used root name for the sun is the Latin word sol, from which comes the words solar, solarium and solstice.\nGiven the prominence of the sun in the sky, it is not surprising that most mythologies include a sun god. The Egyptians called him Ra or Re. To the Hindus he was Surya. To the Mesopotamians he was Utu or Shamash. The Celts called him Lugh. While most mythologies pictured the sun as a masculine god, the..

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Do plants grow faster under certain colors of light?

Experiments involving the effects of different light colors and sources have been ongoing for many years. Even the average elementary school science fair is likely to have at least one demonstration. NASA has also seen the benefit of investigating the long-term and short-term impact of different wavelengths of light on the growth and production rate of vegetables and other plants. What has been discovered is that all plants are very different, though most will respond best to blue or cool colors during their early growth period. Later, unique characteristics change those needs based on their n..

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Where does magma come from?

Before it reaches the Earth, magma reaches temperatures of between 1,292 and 2,372 degrees Fahrenheit. Magma exits the Earth's crust through volcanoes or other vents and becomes liquid lava, where it eventually cools and transforms into solid igneous rock. Lava has the ability to cause chemical and physical changes to the environment and is also able to influence the creation of entirely new land forms.

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How do convection currents move tectonic plates?

The convection currents in tectonic plates occur in the geosphere. The radioactive decay of elements is responsible for the heat deep within the earth, and this results in the creation of magma. Magma is a type of material that can be semi-fluid or completely fluid. It is very hot and when it starts to cool, it forms into igneous rock and lava. Convection currents also occur in wind in the atmosphere and in ocean currents in the hydrosphere.

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What is the structure of the nucleus in a cell?

The word "nucleus" stems from Latin and means "kernel." The nucleus is an important organelle because it coordinates the cell’s genes and regulates gene expression. It is arranged as lengthy linear DNA molecules in conjunction with various proteins to make chromosomes. The inside of the nucleus contains numerous subnuclear bodies made from proteins, molecules and chromosomes.\nThe nucleus acts as the brain of a cell, but it is not always found at the center. It is a dark mass found in the liquid that fills the cell, which is known as cytoplasm. The nucleus is surrounded by a nuclear envelope..

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What happens when water vapor cools?

In the atmosphere, moisture condenses to form clouds at higher levels. When it condenses near the surface, fog forms. Many of these droplets of moisture join and form raindrops. In the atmosphere, water is continually evaporating and condensing. When there are no clouds present, the rate of evaporation exceeds the condensation rate.\nContrails are water vapor that has condensed from the exhaust of a jet plane to form a long thin cloud. Contrails can help to predict the weather. If they disappear quickly or do not form, the weather is likely to remain clear. When contrails remain long after the..

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