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When do leaves start turning yellow?

Yellow leaves are also an indication that a plant is receiving too much or too little sunlight. This occurs mostly with indoor plants.\nIn some cases, the yellowing of leaves is a natural process. For example, in autumn, as the nights grow longer and the temperatures cool, the leaves of some deciduous trees turn yellow and begin to shed.

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What are the four steps of DNA replication?

Unwinding must occur in order for DNA replication. Two strands of DNA that are connected and wound into a double helix separate from each other. This separation creates a replication fork, and enzymes connect the existing exposed bases with complementary free nucleotide triphosphates. To complete the joins, an enzyme called polymerases starts the chemical reaction that allows for the joining of phosphate and deoxyribose sugar. The DNA chain can only continue to extend in one direction. Enzymes called ligases are used to create a continuous and complete DNA molecule.

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What is the definition of DNA for kids?

DNA is a very large molecule that is built up from smaller molecules known as nucleotides. The exact sequence of these nucleotides, much like the sequence of words in a recipe, tells the living cell how to put organic molecules together to form proteins. Unlike a blueprint, to which DNA is often compared, slight changes to DNA can dramatically affect the end product, making the process dependent on the sequence of steps as in a recipe.

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How do you convert feet into square yards?

Measure the lengthMeasure the length of one side of the area. Measure the widthMeasure the width of one side of the area. Calculate the areaMultiply the measured length by the width to arrive at the area of the space in square feet. Compute the square yardageDivide the square footage of the area by 9 to arrive at the number of square yards.

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What countries use the customary system?

Congress chose the American customary system as the national standard early in the country's development, as they are empowered to by Article 1, Section 8 of the Constitution. Thomas Jefferson wanted to use the new French metric system, but was reluctant at that point in history to invest in the necessary trip to France to acquire accurate measurements. Soon afterward, relations between France and the United States cooled, and it was determined that the American customary system was adequately uniform anyway. In the 1860s, the European-standard metric system was adopted as an alternate m..

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What is a change in velocity called?

Acceleration is the rate of change in velocity of an object over time. It is the net result of all the forces acting upon the object. The application of a physical force, such as hitting a ball with a bat, causes it to accelerate, as long as the force is sufficient to overcome the inertia of the object. A falling object accelerates at a constant rate due to the force of the Earth's gravity, until the force of gravity is matched by the force of air resistance. At that point, terminal velocity is reached. The object continues falling at a constant speed, and its acceleration is considered t..

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How long does it take to walk 1 kilometer?

Younger people are expected to walk much faster than older people. Walking is good for the body, and it helps to improve the cardiovascular system and strengthen the heart and lungs. Walking on a regular basis can boost the immune system, assist with weight loss and improve the endurance and strength of the muscles in the lower body.

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What happens in meiosis 1?

Meiosis I takes place over six stages:Prophase I - the homologous chromosomes pair up and form synapses to become bivalents. As the genes recombine, chiasma form.Prometaphase I - the nuclear envelope disappears. Each chromosome gains a kinetochore and those attached to spindle fibers begin to move.Metaphase II - the bivalents containing two chromosomes align at the metaphase plate. How they align is random, which means that either parental homologue can end up on each side. As such, there's a 50 percent chance of the daughter cells inheriting the maternal or paternal homologue.Anaphase I ..

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Why are rainforests being cut down?

On a small and local level, farmers may cut down rainforests to meet their agricultural needs. For example, they may need somewhere to grow their crops or let their cattle graze. This usually involves removing a few acres of trees their trunks to make way for arable land. Many farmers who do this have no other means of making money, which means their activities support their basic needs.In contrast, commercial deforestation occurs on a much larger scale, with miles of trees disappearing at once. Sometimes this is done to produce cheap timber and pulp, or to create large cattle pastures for glo..

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What is Stephen Hawking's IQ?

An average IQ score is 100. Those with an IQ below 70 are considered to be intellectually disabled and those with an IQ over 130 are considered to be gifted. Abdesselam Jelloul has the highest recorded IQ. Jelloul took an advanced IQ test in 2013 and scored 198. The advanced IQ test Jelloul took measures 13 dimensions of intelligence.

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