Discuss the chain of events that led to the discovery of DNA as the heritable substance and the discovery of the structure of DNA. Ans> The chain of events led to the discovery of DNA as the heritable substance and the discovery of the structure of DNA. In the late nineteenth century‚ a German biochemist Friedrich Miescher found the nucleic acids which are long-chain polymers of nucleotides‚ and are made up of sugar‚ phosphoric acid‚ and several nitrogen-containing bases. Later it was found
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LAB 4: KIRCHHOFF’S RULES DIY Lab This section is adapted from reference 1. Objective In this experiment‚ you will experimentally verify Kirchhoff’s rules by measurement and by mathematical analysis. Apparatus (Lab Kit* or NIC Lab) 5 resistors one 6V battery or power supply (each under 1.5 kΩ each‚ not all equal) digital multimeter 12 connecting wires *If you do not have the Lab Kit‚ you can use equivalent items. Contact your instructor regarding equivalent items to ensure that the objective
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JOHN BAPST HIGH SCHOOL NAME : Luis Adrian Vega Alvarez PERIOD: 5 COURSE : Junior 1. Background 1.1. One of the most vigorously debated topics on Earth is the issue of climate change‚ and the National Environmental Satellite‚ Data‚ and Information Service (NESDIS) data centers are central to answering some of the most pressing global change questions that remain unresolved. The National Climatic Data Center contains the instrumental and paleoclimatic records that can precisely
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Emulsifiers What does an emulsifier do? Emulsions in food are mixtures of oil and water. These normally do not mix and will separate if left without an emulsifier. Emulsifiers are among the most frequently used types of food additives. They are used for many reasons. Emulsifiers can help to make a food appealing. The example of the mayonnaise without the emulsifier shows how unappealing it would be if the oil and water separated before it was used. Emulsifiers have a big effect on the structure
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Hypothesis: I predict that the leaves taken from the outer area of a shrub have a higher stomatal index (/density) than those taken from the centre of a shrub this are due to light levels. Explanation: Plants have stomata to obtain carbon dioxide from the atmosphere and remove oxygen produced in photosynthesis. During photosynthesis the chloroplasts in the leaf cells synthesize as a result of exposure to light‚ while oxygen is produced as a by-product. As the outer leafs are exposed to higher light
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Unit 5 Case Study Mariella Hines is a 9 year-old African-American girl attending the 3rd grade in the JFK School. She was referred to the School Psychologist because she has recently become very withdrawn during class‚ refusing to speak to anyone‚ including her teacher and peers. Previously she seemed to have age-appropriate social skills‚ interacting well at school. Her withdrawal started suddenly. Mariella’s teacher‚ Mrs. Levine‚ called Mariella’s mother to find out more information‚ but her
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"Rewilding North America" by Caroline Fraser‚ focuses on the negative outcomes of human activities in the environment. It is a movement that restores the environment that humans have damaged. Scientists have addressed the idea‚ in "A life of its own" by Michael Specter‚ of using synthetic biology to mend environmental issues. Synthetic biology combines the "elements of engineering‚ chemistry‚ computer science‚ and molecular biology…to assemble the biological tools necessary to redesign the living world"
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Extended experimental investigation: effects on membranes of environmental stress Background It is not possible to observe membranes directly‚ so this investigation is an indirect study of the effects of different substances and treatments on living beetroot cells. Beetroot cells have been chosen for this activity because each beetroot cell has a large central vacuole bounded by a membrane (Figure 1). Contained in the vacuole is the red pigment anthocyanin‚ which gives the beetroot its
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# 49 Diet The food an animal eat everyday is called diet. Most animals need 7 types of nutrients in their diet: carbohydrates‚ proteins‚ fats + water‚ fibre‚ vitamins‚ minerals. The amount of energy needed is provided mainly by our carbohydrate and fat intake. Your dietary requirements depend on your age‚ sex and activity. - Age: The energy demand increases until we stop growing. While children are growing they need more protein per kilogram of body weight than adults do. - Sex: Generally
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Dry Wallum The dry wallum is a harsh environment that is battered by the sun and wind every day and with a base of porous sand; water availability is very scarce and must be conserved. The abiotic factors in the dry wallum are that the area is exposed to high amounts of sunlight which causes a loss of water in the leaves through transpiration. Since the wallum is so dry and hot; bush fires play a major cycle in the dry wallum which the trees have adapted to cope with. The roots of the plant and
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