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What are the four stages of an animal's life cycle?

The basic life cycle of an animal starts with an egg, which becomes an embryo upon fertilization. It then develops into an immature individual that resembles an adult, and finally grows into a mature adult. For instance, a bird starts out as an egg. Once the egg is laid, the embryo inside begins to grow. When enough time passes, it hatches, letting out an immature bird. That baby bird eats and grows until it develops into an adult.\nAnother example is the polar bear, a mammal. Instead of laying eggs, the egg inside the female is fertilized by the male. The fertilized egg becomes an embryo, dev..

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What is the difference between speed and acceleration?

To calculate the speed of an object, the distance traveled is divided by the time taken to travel that distance. If an object is gaining or losing speed, it is said to be accelerating.\nSpeed, unlike acceleration, cannot be negative. This is because speed is a scalar quantity, which means it does not include the direction an object is moving. Acceleration is a vector quantity, which means it shows how fast an object is changing speed and the direction in which the speed is changing.\nAcceleration is calculated by finding the change in speed over a period of time, and then dividing this change ..

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What month is fall?

The autumnal equinox occurs around the third week of September and is the point on the calendar when the number of daylight hours roughly equals the number of nighttime hours (about 12 each). On this day, the sun rises at due east and sets at due west, following the celestial equator. Sunrise and sunset only align exactly with the celestial equator on the spring and fall equinox.

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What moves the chromatids during mitosis?

Mitosis begins after interphase ends, and the nuclear material of the cell is replicated. The first phase of mitosis is called prophase, during which the DNA that has been replicated condenses into an X-shaped body. The next phase is called prometaphase; during this stage, the nuclear membrane breaks down into vesicles, which allows microtubules to invade the nuclear space of the cell.\nMetaphase follows prometaphase, when the chromosomes begin to align at the equator of the cell and the microtubules from each pole attach to the kinetochores of the chromosomes. Anaphase is the next phase, and ..

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What happens when you combine milk, food coloring and dish soap?

The dish soap is essential to cause the separation reaction to occur. When mixed with milk, it bonds to the fats it contains, creating micelles that cause the surrounding molecules to be pushed away. This lowers the surface tension of the milk and allows the food coloring to spread throughout the liquid.\nThe fats in the milk are important to cause a stronger reaction. If the milk has a lowered fat content, it results in a weaker, less visually pleasing result.

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How do paramecia regulate their water content?

The contractile vacuoles paramecia used to eliminate excess water are physical pumps. They fill with water and then contractile fibers squeeze the vacuole and force the water out. This method of removing excess water is shared by many other single-celled organisms such as amoebas.\nParamecia are typified by their use of cilia, tiny hairs on the outside of their cell membranes, for use in locomotion. Their primary food source is bacteria in the stagnant water, which is their most common habitat. They also consume other organisms such as yeasts and algae. At least one species of paramecium forms..

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Why do we need to conserve water?

Only around 3 percent of the world's water is freshwater, and more than two-thirds of that total is frozen into glaciers and icepack. Another 30 percent is groundwater, leaving a perilously small supply of freshwater at or near the surface that is available for use.\nWater conservation can also save energy. Areas with poor natural water supplies must have water pumped in from elsewhere. In California, approximately 6.5 percent of all energy use in the state is devoted to moving water into dry areas.\nThe average American uses 100 gallons of water per day. Additionally, as many as 10 perce..

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What are the five steps of hypothesis testing?

Stating the null and alternative hypotheses is an essential first step, because this is what you're going to test. The alternative hypothesis is what you think the data will show, and should be based on previous data or an educated guess. The null hypothesis is the case where that is not true.\nDetermining the test statistic means choosing between doing a Z test or a t test. The t test is more commonly used because, unlike the Z test, it is not necessary to know the standard deviation.\nDetermining the probability of test statistics means computing what is known as the p-value. Methods fo..

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What are some examples of sustainable development?

Crop rotation, such as alternating wheat with local crops, prevents soil from becoming too saturated with salt or becoming infertile due to a loss of minerals. Another sustainable farming practice is growing crops beside or beneath local crops, such as growing coffee plants in a forest instead of fields solely composed of coffee plants. Comparable sustainable practices in cities include the use of green spaces, which reduce temperatures caused by an overabundance of concrete, glass and metal and which minimize excess water runoff during storms.\nWind and solar energy provide sustainable source..

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In simple terms, how is a tornado created?

Not every thunderstorm turns into a tornado, fortunately. There has to be enough moisture at the lower levels of the atmosphere for the storm to be strong, and a triggering event, such as a cold front or other confluence of winds, is also necessary to hold that moist air. After the air starts rising and finds saturation, it keeps going to make a thunderstorm cloud. As the air goes up, if it cools dramatically, instability begins to increase. If the winds are moving in a clockwise direction, tornadoes are more likely.\nIf one notices a funnel cloud starting to form, it is the beginning of a tor..

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