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What is the role of chlorophyll in photosynthesis?

A pigment is a molecule that will absorb a specific range of light wavelengths while reflecting those not included. The pigment chlorophyll a, one of two types of chlorophyll found in plants, absorbs light primarily at the wavelength of 430 nm (blue), and to a lesser extent, at the wavelength of 662 nm (red). Chlorophyll a absorbs light poorly in the electromagnetic spectrum occupied by the color green, so it is reflected back and gives plant tissues containing the pigment their green appearance.Because it contains a fat-soluble phytol chain, chlorophyll can remain embedded within a lipid memb..

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How long can it take food to travel through the small intestine?

The small intestine digests food chemically by secreting chemicals that break down the food. Once the food has been broken down, small blood vessels that line the small intestine absorb the nutrients. Interestingly, food takes much longer to travel through the large intestine than the small intestine, despite the fact that the small intestine is much longer in length. According to research the Mayo Clinic conducted in the 1980s, it normally takes about 40 hours for food to pass through the large intestine.\nWhen food is eaten, it passes through the mouth, esophagus and stomach before reaching ..

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How do you keep hawks out of the yard?

Several species of hawks are dangerous and aggressive. One of the most effective ways to keep small animals safe from these raptors is by building a life-size scarecrow and displaying it in an area that often contains small animals. Scarecrows, if built large enough, are not only an effective way to keep the hawks away, but a humane method as well. Another way to keep hawks away from property is by increasing the amount of human activity in the area. Hawks generally don't bother prey larger than they are, so they tend to leave people alone. It is important to remember that hawks and owls ..

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What process takes place inside chloroplasts?

Just like animals, plants need energy to carry out their basic functions of survival. They produce their energy by combining carbon dioxide, nutrients, water and sunlight. Thylakoids are disc-like shapes that trap the sunlight for this purpose, which are stacked inside chloroplasts. The thylakoids contain chlorophyll, which is what gives plants their green color.\nGenerally, the plant uses these thylakoids to convert sunlight and carbon dioxide to glucose, a sugar that is usable by the plant. Plants release oxygen during the photosynthesis process, which is the opposite of what animals do. Hum..

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What is a four-legged animal called?

Four-legged creatures use a quadrupedal form of terrestrial or arboreal locomotion that utilizes four limbs. Quadrupeds that are adapted to moving on land are characterized by several distinctive features, including narrow mid-sections, equally-long forelimbs and hind limbs, limited shoulder joint mobility, shortened tails and stubby digits.Arboreal quadrupeds that predominantly live in trees share similar traits with terrestrial quadrupeds. These animals also have a slender thorax and equally-long frontal and hind legs. However, arboreal quadrupeds have movable shoulder joints, longer tails a..

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What element is H2o?

Cavendish discovered how hydrogen and oxygen worked together when he took the two and mixed them together. The reaction was an explosion called the oxyhydrogen effect. In 1811, Italian physician Amadeo Avogadro found the formula for water. It didn't take long for him to understand that water is the only element that can exist as a solid, gas and liquid.Since the first discovery of water, much has been learned about the element. It is a bad heat conductor and an excellent solvent and means of transport. Without water, life on Earth would cease to exist.

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What is the chemical composition of cerebrospinal fluid?

Produced from arterial blood, CSF cushions the brain from trauma and is important to homeostasis of the central nervous system. Cerebrospinal fluid is produced in the lateral and fourth ventricles of the brain by the choroid plexuses. The total volume of CSF in an adult ranges from 140-270 milliliters, and about 600-700 milliliters are produced per day.\nVariations in the composition of CSF can indicate pathology. Increased protein content can be indicative of meningitis, subarachnoid hemorrhage or cerebral infarction. In patients with Cretzfeldt-Jacob disease, there are elevated levels of tau..

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When might an intravenous iron infusion be necessary?

Iron is found in hemoglobin, a material that helps red blood cells deliver oxygen to the body. Iron deficiencies can be caused by excessive blood loss, such as in bleeding ulcers, iron-poor diets, medications that inhibit the body's absorption of iron and, in the case of pregnancy, when the body requires more iron than usual. Any of these factors can cause iron-deficiency anemia.\nPhysicians first try changing the patient's diet, combined with oral iron supplements. Some patients can't tolerate the tablets, so they may have to have intravenous iron treatments. The supplement is ..

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What is an example of a dicot seed?

In 1682, John Ray introduced the taxonomic division of flowering plants into monocots and dicots, a division that is still widely used as of 2015, even though there are some plants that mix characteristics of the two groups. As a general rule, monocot seeds differ from dicot seeds in having only one seed leaf rather than two within the seed coat. In addition, the seed leaf of a monocot seed does not contain the endosperm that feeds the new plant, while the seed leaves of dicot seeds do contain endosperm.

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What is the Lewis structure for SEO3?

In the Lewis dot structure, the Se represents the element selenium, and each O represents oxygen. Each single line indicates a single pair of bonded electrons, while the double line represents two pairs of bonded electrons. The single dots represent one valence electron each.\nSeO3 is the chemical formula for the compound selenium trioxide. Different Lewis structures of the same compound are known as resonance structures.

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