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What is the failure of chromosomes to separate during meiosis called?

Most cells in the human body contain 23 pairs of chromosomes, with one copy of each pair inherited from the mother and the other copy inherited from the father. The first 22 pairs of chromosomes are autosomes and the last pair is sex chromosomes. According to "An Introduction to Genetic Analysis," aneuploidy may result in extra autosomal genetic disorders, sex chromosome disorders or termination of the developing fetus.

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What is the history of the U.S. space program?

Project Mercury concluded in 1963 and was the first of three major manned missions. The second, Project Gemini, was announced in 1962 and featured 10 manned, and two unmanned, orbital flights. Following President Kennedy's imperative to reach the moon, NASA launched Project Apollo. Apollo 11 successfully landed on the moon on July 20, 1969. The Apollo project ran for several more missions, and the Saturn V rocket it used was later adapted to carry the Skylab space station into low Earth orbit. Beginning with the April 1981 launch of the space shuttle Columbia, NASA focused on developing r..

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What is the chemical name for K2HPO4?

K2HPO4 is a pesticide that is registered for legal use in the United States by the U.S. Environmental Protection Agency. Although the EPA has determined that K2HPO4 use doesn't harm humans, it has toxic effects on fish, and it reduces phytoplankton populations, according to the Pesticide Action Network. Phytoplankton provide food for many aquatic animals and release oxygen from carbon dioxide.

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What is biological inheritance?

The features that can be passed down through generations are called heritable characteristics. These traits are transmitted from parents to their offspring and include physical characteristics that have unique genetic codes and cellular structures. In organisms that reproduce sexually, traits from both parents are combined and passed along to unborn babies: these traits contain unique attributes of the mother and father, but also contain some novel components, which explains why children share many commonalities with their parents but also have some cellular and physical differences too. In ad..

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What are some facts about the dwarf planet Ceres?

In addition to being the first asteroid to be discovered, Ceres is also the largest. It is roughly spherical and approximately 980 kilometers across. Set next to Earth, it would reach from El Paso to the Texas-Louisiana border. Ceres has a surface area of 2.85 million square kilometers, which means that if it could be spread out in two dimensions, it would cover an area somewhat larger than Argentina.\nCeres and the other asteroids of the Main Belt are remnants of the solar system's earliest period. Gravitational tugs from Jupiter and Mars prevented these asteroids from accreting into a f..

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What is surface tension?

The surface tension of a liquid results in a skin, which resists external forces. Liquid molecules, such as those in water, have a tendency to cling to each other. With no water molecules above them at the surface, they exert stronger clinging tendencies to the molecules below them and to their neighboring molecules around them. This surface tension allows small objects to float upon the surface of the water.

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What is Saturn's average temperature?

There are three layers of clouds on Saturn, with the inner layers being increasingly warmer. The outer layer's temperature ranges from -280 to -170 degrees Fahrenheit, or -173 to 113 degrees Celsius. The middle layer maintains temperatures of -127 to 26 degrees Fahrenheit, or -88 to -3 Celsius, while the inner layer gets as warm as 134 degrees Fahrenheit, or 57 degrees Celsius. The rocky core may reach temperatures of up to 21,000 degrees Fahrenheit, or 11,700 degrees Celsius.

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What are examples of external fertilization?

Most frogs need to lay their eggs in a body of fresh water. The male frogs call from the edge of a pond or stream and attracts the females. During the external fertilization, the male grasps the female in what's called amplexus, and they enter the water. She then releases her eggs at the same time he releases sperm. The fertilized eggs hatch into tadpoles.\nMany species of salmon return to their natal streams to reproduce. The female digs a nest, or a redd, in the stream bed and deposits eggs in it. The male then swims over the nest and fertilizes the eggs.\nCoral animals don't even..

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How is a kidney transplant done?

A kidney transplant surgery is preceded by the insertion of intravenous tubes on the hand, arm, groin or under the collarbone, explains Johns Hopkins Medicine. These tubes are used to monitor a patient's heart and blood pressure during the procedure and to obtain blood samples. With the patient under general anesthesia, a tube is then inserted into the lungs through the mouth and attached to a ventilator. After that, the surgical site, usually located on the lower abdomen, is shaved and cleaned.\nAn incision is then made on the surgical site, explains Johns Hopkins Medicine. Before the pr..

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Does glass conduct heat?

The concept of glass being a poor conductor of heat is illustrated by cooking equipment. Metal materials, such as iron and copper, are often incorporated in cooking tools, such as grills, trays, utensils, sheets, pots and pans. Along with glass, plastic and wood do not conduct heat as well. Conduction is one of the three methods of transferring energy, including convection and radiation. Conduction requires objects to be in contact with one another.

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