Osmosis in potato experiment

,BIOLOGY INTERNAL ASSESMENT Osmosis experiment DCP & CE OSMOSIS IN POTATO DATA COLLECTION AND PROCESSING: a. Raw Data: table (1): initial and final weights of potato cubes at soaked in different sucrose solutions 3rd trial (final weight) (g)(±0.05) 2nd trial (final weight) (g)(±0.05) st trial (final weight) (g)(±0.05) Potatoes (initial weight) (g)(±0.05) Sucrose solution Molarities (mol/L) 0.7 0.8 0.9 0.6 0.1 .3 .3 .3 .1 0.2 0.9 0.7 0.8 0.7 0.3 0.9 0.9 0.9 0.9 0.4 .5 .4 .5 .7 0.5 .0 0.9 .0 .1 0.6 0.8 0.9 0.8 .0 0.7 0.7 0.7 0.7 0.9 0.8 0.4 0.5 0.5 0.7 0.9 0.7 0.7 0.6 .1 .0 b. Processed Data: - The average final weight is obtained using the following rule: - The percentage change is obtained using the following rule: table (2): percentage change of potato cubes weight in different sucrose solutions: Percentage change in the mass of potato cubes Difference between final and initial weights in (g) (±0.1) g Average final weight (gram) (±0.05) g Sucrose solution Molarities (mol/L) 33.3 % 0.20 0.80 0.1 8.2 % 0.20 .30 0.2 4.2 % 0.10 0.80 0.3 00.0 % 0.00 0.90 0.4 -14.1 % -0.24 .46 0.5 -12.7 % -0.14 0.96 0.6 -17.0 % -0.17 0.83 0.7 -22.2 % -0.20 0.70 0.8 -34.3 % -0.24 0.46 0.9 -40.0 % -0.44 0.66 .0 The previous data in table (2) is represented by the following

  • Word count: 614
  • Level: International Baccalaureate
  • Subject: Biology
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Calibration curve

Calibration Curve Aim: In this experiment the basic aim is to make a calibration curve for the concentration of glucose Hypothesis: As the glucose concentration increases the time taken for it to turn colourless will decrease. Variables: Independent- Concentration of Glucose Dependant- Time taken to de-colourize the potassium Constant- Amount of sulphuric Acid and the other material used Apparatus: . 1 stop watch 2. 11 test tubes 3. 1 test tube stand 4. 11 rubber stoppers 5. 150ml of glucose solution of 10g/dm3 6. 30ml of 0.01mole potassium permanganate solution 7. 60ml of 1M sulphuric acid 8. 4 plastic syringe of 20ml 9. 4 beakers 0. 10ml distilled water in wash bottle 1. Marker (pen) Method: . Obtain the 11 test tube and places them in the test tube stand. 2. Label each test tube from 0 - 10 using the marker. 3. Using the syringe add different quantities of glucose in each test tube. In the test tube labelled '0' add no glucose. In the test tube labelled '1' add 1ml of glucose, now in the same way continue this process until u have filled the last test tube with 10ml. 4. Now different amounts of distilled water must be added into each test tube using a different syringe. It follows the same procedure as glucose. In the test tube labelled '0' 10 ml of distilled water should be added. In the test tube labelled '1' 9 ml of distilled water

  • Word count: 925
  • Level: International Baccalaureate
  • Subject: Biology
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Research Question To what extent does watching different genres of movies affect our sympathetic and parasympathetic nervous systems, causing changes in heart rate?

Factors affecting heart rate Research Question To what extent does watching different genres of movies affect our sympathetic and parasympathetic nervous systems, causing changes in heart rate? Introduction There are many reasons which cause change in normal heart rate (60 - 100 beats per minute). Watching different genres of movies causes our sympathetic and parasympathetic nervous systems to release certain hormones particular hormones which make us react in different manners. The sympathetic components increase heart rate by releasing the neural hormone catecholamines - epinephrine and norepinephrine. These hormones are cardio accelerators. Acceleration of the heart rate is called tachycardia. The parasympathetic nervous system located in the brain stem and upper or sacral portion of the spinal cord slows heart rate. The parasympathetic components decrease heart rate. These neurons release the neurohormone acetylcholine, which inhibits heart rate. The slowing of heart rate is called bradycardia. Another major role playing hormone is adrenaline which causes an immediate hike in the heart rate. Hypothesis Different stimulus causes different changes in heart rate because of varied responses from the sympathetic and parasympathetic nervous systems. Watching horror and action movies should cause a greater increase in the heart rate, whereas, comedy and romance are more

  • Word count: 804
  • Level: International Baccalaureate
  • Subject: Biology
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Penicillin - its discovery, properties and uses.

Introduction Penicillin is a familiar word to everyone. The first idea that comes to people's mind is Penicillin is a group of antibiotics, as Penicillin is a very common antibiotic that kills bacteria. Apart from killing bacteria, what else do people know? Probably is nothing. In this project, I would like to find out what do Penicillin is and how people discovery Penicillin. First of all, go with the basic thing, what antibiotic1 is. Antibiotics are molecules that stop microbes, both bacteria and fungi, from growing or kill them outright. Antibiotics can be classified as either bactericidal or bacteriostatic. Antibiotics that stop bacteria from growing are bacteriostatic. Antibiotics that cause bacterial cell death are bactericidal. They lower the bacterial count, penicillin, is bactericidal. Some antibiotics can display bacteriostatic activity in some circumstances and bactericidal activity in other, where sufficient damage to one or more cell pathways or structures occurs such that a net bactericidal response is triggered. Many antibiotics are bacteriostatic at low concentrations and bactericidal at higher concentrations2. This distinction is often not important clinically. Antibiotic can either be natural products or man-made synthetic chemicals. Most of the antibiotic introduced into human clinical use to treat infections disease in the past 60 years have been natural

  • Word count: 4653
  • Level: International Baccalaureate
  • Subject: Biology
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affect of light intensity on rate of photosynthesis

Biology experiment: photosynthesis The effect of light intensity on Inelodea's rate of photosynthesis Aim: Investigating the effect of increasing light intensity on rate of photosynthesis of Inelodea (water plant) Light intensity is manipulated by changing the distance of the beakers from the lamp Rate of photosynthesis is measured by looking at the pH change of NahCO3 solution. CO2 makes water more acidic. As CO2 is gradually used up during photosynthesis, the change in pH of the solution per time implicates the rate of photosynthesis. Hypothesis: The increase of light intensity will increase the rate of photosynthesis of Inelodea Apparatus: * 5g of NaHCO3 (powder) * 5 beakers (100 ml) * Stirring rod * Balance * Universal pH indicators * 5 Inelodea plants (7 Cm long) * Distilled water * Lamp * 1 metre long ruler * Stop watch Method: ) Fill each of the 5 beakers with 75 ml of distilled water 2) Dissolve 1g of NaHCO3 (use balance to weight NaHCO3) in water to give CO2 supply 3) Mark each beaker with letters A, B, C, D, and E 4) Measure pH level of the 5 beakers before the experiment 5) Place same size Inelodea (7 cm long) in to beaker A 6) Place the beaker 20 cm apart from the lamp (using ruler to measure this distance) 7) Measure the pH of the solution each 2, 4, 6 and 8 minutes 8) The experiment is repeated for beakers B, C, D with distance 40 cm,

  • Word count: 1045
  • Level: International Baccalaureate
  • Subject: Biology
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Amylase Lab

Hypothesis: After swabbing the starch auger with the source, a positive reaction will occur if amylase is present in the source. Hypothesis of Reaction of Sources Substance Number Substance Shape Reaction Hypothesis Carrot Carrot Negative ( - ) 2 Saliva Smiley face Positive ( + ) 3 Radish Ball Negative ( - ) 4 Snow Pea Sun Negative ( - ) Independent Variables: amylase source Dependant Variable: quantity of starch digested by source DC Reaction of Sources Substance Number Substance Reaction Shape Reaction Blue Color Intensity Carrot No shape visible Negative ( - ) 5 2 Saliva Clear smiley face Positive ( + ) 0 3 Radish Faint ball Positive ( + ) 3 4 Snow Pea No shape visible Negative ( - ) 5 Key: Blue Color Intensity of Shape 0 - no blue is present - faint blue 2 - light blue 3 - medium blue 4 - blue 5 - dark blue Conclusion The hypothesis that was stated in the beginning was proven by the reaction of the sources to the starch auger. The sources that had the most amylase in their makeup were the saliva and the radish. This was seen by the positive reaction by the auger after iodine was added to it. A positive reaction was determined by how light or dark the location that the source was swabbed appeared when blue iodine was added to it. The saliva was seen to have the most amylase in its makeup because it was most clearly

  • Word count: 874
  • Level: International Baccalaureate
  • Subject: Biology
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Lung Capacity Fitness Level

High Level Biology Human Physiology 1 Digestive or Respiratory System Open Investigation Will increasing levels of fitness enable one to have larger vital lung capacity? DESIGN Background Information Notice how short distance professional swimmers, for example, a 50m freestyle swimmer, breathe only once or twice throughout the whole course. Why is it that it is nearly impossible for normal recreational swimmer to do that? If a person's lung size cannot increase, how is it possible for professional swimmers to have such large lung capacity thereby able to hold large amount of air? The answer has to do with fitness level and exercise. Breathing comprises of two actions, inspiration and expiration. Breathing is one of the required bodily functions of human beings. Our lungs deliver oxygen breathed in (inspire) from our surrounding air into the blood inside our body, and contrary exhale (expire) carbon dioxide out of the body. When inspiration occurs, the diaphragm and the intercostal muscles contract and causes the diaphragm to move downwards, increasing the volume of the chest cavity. The intercostals muscles also causes the rib cage to expand, further increasing the volume. Contrary to inspiration, expiration causes the diaphragm and intercostal muscles to relax therefore the thoracic cavity returns to its original volume, increasing the air pressure in the lungs and

  • Word count: 6468
  • Level: International Baccalaureate
  • Subject: Biology
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Carrot growth with differing wavelegnths of light

Introduction: Daucus carota is a root that has small flowers but is capable of self fertilization and is biennial since it grows vegetatively in the first season and produces seeds in the second (Plants for a future 2008). It was originally native to Asia in colors ranging from purple to yellow to white with orange being the most prominent today (Carrots). The Daucus carota is capable of growing in many different conditions and regions from Asia to the Americas and Europe and Africa as long as there is direct sunlight (Carrots). This plant is hardy since it can grow in many temperatures from 10°C to 25°C, however from 15°C to 20°C is optimal, but can still grow in colder conditions, though much slower (Carrots). Daucus carota also prefers loose, deep soil that is well irrigated, but in more compacted soil it can grow however the root tends to be crooked or split. (Carrots). Lastly, this plant can grow in many pH ranges from 4.2 to 8.7 with 6.5 to 7.5 being the optimal range (Plants for a future 2008). In order for photosynthesis to occur, there must be a light source to provide energy for the necessary reactions. This experiment will use different wavelengths of light to discover which one promotes growth the most for Daucus carota. Explained by the action spectrum diagram, different colors of light promote growth more or less efficiently than others. As shown, light in

  • Word count: 3107
  • Level: International Baccalaureate
  • Subject: Biology
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Biology Cell Lab

Biology Cell Lab Design Question What are the differences between the structures and sizes of plant and animal cells? Materials Microscope Slide Cover slip Water Elodea Human Wooden stick Methylene blue Procedure The microscope was set up and the elodea leaf was picked off using tweezers and placed on a slide. A drop of water was added to the slide and a glass cover was dropped at a 45 degrees angle. The slide was examined under the microscope starting at the low objective lens then the medium objective lens and lastly the high power objective lens. The diagram of the elodea was drawn and the measurements were written down. Next, the human cheek cell slide was prepared. A drop of water was added to the slide and saliva scraped from the side of the cheek using a wooden stick was dabbed onto the drop of water. Then a drop of methylene blue was added to the mixture and a slipcover was placed on top of the specimen. Data Collection and Processing Raw Data Table Length (µm ±50µm) Width (µm ± 50µm) 26.7 22.9 50 33.3 56.3 34.6 84 42 84 52.5 00 50 00 50 67.4 31.8 55 22.5 70 40.7 70 44.5 70 21 Mean= 77.7 Mean= 37.2 Class values of the sizes of Elodea Class values of the sizes of Human Cheek Cell Length (µm±50µm) Width (µm ± 50µm) 46.7 30 32.1 40 34.3 30 53 53 36.2 38.2 32 31.6 70 26 51 38.2 46.7 30.5

  • Word count: 1098
  • Level: International Baccalaureate
  • Subject: Biology
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How are interactions between neural cells established and maintained?

How are interactions between neural cells established and maintained? The human embryo is a collection of clusters of non-specific cells, which then develop into the tissues of the adult human. In particular immature, non-specific neuroblasts must be differentiated into the highly specialised cells of the nervous system, each with a unique structure, function and synaptic interactions (Whatson 2004). The whole function of the nervous system relies on the synaptic and other interactions between neural cells being developed appropriately and maintained throughout life. This account covers the initial development of specific neural cells from immature precursor stem cells and also the methods by which the growing specialised neurons grow along the correct routes to form their interactions with other cells, both neuronal and non neuronal. Establishing neural cells from stem cells Progenitor or stem cells are non-specific immature cells that are able to differentiate and form specialised cells in the adult organism. There are relatively few types of neural stem cells, with the potential to differentiate into many different types of specialised neural cells, depending on specific, localised requirements. Multipotent (able to form many types of daughter cells) neural stem cells were first identified in the early 1990s (Imitola et al. 2004) and subsequent research has focussed on

  • Word count: 1440
  • Level: International Baccalaureate
  • Subject: Biology
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