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What is the function of a cell membrane?

Proteins and lipids make up the composition of a cell membrane. There are three different types of proteins found within a cell membrane: structural protein, transport protein and glycoprotein. These support cell structure and shape, move molecules through the membrane and transmit signals between cells.\nCholesterol is a lipid found in cell membranes. This lipid is not found in plant cells. Glycolipids are also found in cell membranes. These have a carbohydrate component and help provide energy to cells.\nOther structures found within a cell are the nucleus, mitochondria and chromosomes.

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What is the gram formula mass of Al2(SO4)3?

The molecular weight of Al2(SO4)3 can be obtained by using the atomic weights of the atoms making up the molecular formula. The atomic weights of aluminum, sulphur and oxygen are 26.9815, 32.066 and 15.9994 respectively. The molecular weight of a substance expressed in grams is called a mole. Hence, 1 mole of Al2(SO4)3 is 342.15 grams of aluminum sulphate.\nAluminum sulphate is prepared by the reaction of aluminum hydroxide with sulphuric acid.

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How do fossils form?

According to How Stuff Works, the process of fossilization takes place over millions of years. Usually, the process begins when an animal or plant dies in a place with moving sediment, such as the benthic zone. This is the deepest part of a body of water, and animals, such as dinosaurs, that fell in this zone were quickly covered by sediment. The sediment protected the dinosaurs' bodies, which eventually decomposed, leaving the bones, teeth and claws intact.\nWhen fossils form, the organic parts of the bone, such as the blood vessels, collagen and blood cells, break down; only the inorgan..

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Do heavy objects fall faster than light ones?

In an atmosphere, simultaneous falling requires both objects to have a similar aerodynamic shape. For instance, a one-pound metal sphere and a one-pound sheet of metal fall at different rates, because the greater surface area of the metal sheet creates more wind resistance. Two spheres of different weights but similar size fall at the same speed, since the airflow over their surface produces the same effect on each object.\nGalileo demonstrated this principle in his famous Leaning Tower of Pisa experiment in 1589. He dropped two balls of different masses from the top of the tower, and both rea..

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What is a body part that starts with the letter "Q"?

The QL muscle has four sides and tapers somewhat at the top. Its functions are to support the stability and the movement of the vertebrae and the pelvis. It also aids the body in breathing by fixing the 12th rib during an expiration.\nThe QL muscle has been implicated in some patients' episodes of lower back pain.

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What is kinetic friction?

Friction is a force that occurs between two or more surfaces of objects that is typically in the direction opposite to the force being applied on an object. It can be calculated by multiplying the coefficient of friction by the normal force, which takes into account gravity and any other forces perpendicular to the surfaces in contact. The static coefficient of friction is used when the object is stationary, and is usually larger than the kinetic coefficient of friction, which is used during movement.

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What is the definition of hydraulic pressure?

Dynamic pressure is a type of kinetic energy that has its application found in moving water. In hydraulics, differential pressure meters register the pressure points by the resistance found between two points in the pipelines involved. Differential pressure is also known as the pressure drop.Static pressure is potential energy. This pressure is applied by water that is not moving or that is considered to be at rest. Static pressure is generated by gravitational fields.

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Is C2H2 polar?

For a molecule to be polar, there must be a net charge. This requires that one part of the molecule be more electronegative than the rest of the molecule, and that it not be balanced elsewhere in the molecule. For ethyne, the electronegativities of the carbons cancel out, and the electronegativities of the hydrogens cancel out. The molecule is therefore nonpolar.

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How do you calculate the ionization energy of atoms?

One of the two main methods of calculating the ionization energy is the Koopman’s theory, which involves the HOMO. In this method, the ionization energy of a molecule or an atom is equal to the orbital energy from which it was ejected. The equation is given by Ii = -ei.\nWhere ei is the orbital energy and i is the orbital where the electron was located before the ejection. This formula is ideal for hydrogenic atoms. In fact, it gives an approximation for other atoms because it does not account for the movement of the electron after its ejection. However, it assumes that the electrons remain ..

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What is the Lewis structure for H2S?

H2S is the chemical formula for hydrogen sulfide, an inorganic, flammable gas that smells similar to rotten eggs. Although the Lewis structure of hydrogen sulfide closely resembles that of water, or H2O, the two substances have very different chemical properties. Sulfur is a more electronegative element than oxygen, which results in hydrogen sulfide molecules being less polar than water molecules. As a result, the intermolecular forces keeping the atoms of a hydrogen sulfide molecule together are weak compared to water, and hydrogen sulfide boils at much lower temperatures. The boiling point o..

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