- Join over 1.2 million students every month
- Accelerate your learning by 29%
- Unlimited access from just £6.99 per month
International Baccalaureate: Biology
Meet our team of inspirational teachers
The main purpose of cellular respiration is to produce energy which can be used by living organisms to complete different tasks. Yeast is able to perform both types of respiration. When oxygen level depletes yeast functions anaerobically and then carries out Ethanol Fermentation. Fermentation in brewer's yeast is used in industries to manufacture baked good and alcoholic beverages. Depending on the substance being fermented the variety of Yeast being used, and carbon dioxide availability produced during the process yeast fermentation may be used to produce different substances like wine, champagne, syrupy drinks and ciders.
- Word count: 1625
In this sense I will prove that all biotic features depend strongly upon their environment. I will also prove interconnection of various organisms found in the environment by displaying food chains, and food webs. This will prove that organisms are highly dependant on other organism in their community. Environmental conditions such as temperature and soil pH will also be observed during this experiment. Variables Dependant Variables: * Air temperature (at ground level and 1m above ground) * Soil temperature * Soil pH Independent Variables: * Biotic factors Apparatus * 1x Measuring tape * 2x Thermometer * 2x pH meter *
- Word count: 987
Variables: Independent variable --> They type of potato used --> The molarity of the sugar solution Dependent Variable --> Weight change in the pieces of potato in the 20 hour period Fixed Variables: -The volume of solution that is used in each test tube - The initial weight of the potato when placed in the test tube. Materials: - 1 Big potato 10 g - 1 Big Sweet Potato 10 g - Cutting Blade - 1 Test Tube Rack - Distilled Water - 5 different types of sugar solutions 0.0M, .25M, .50M, .75M, 1.0M - Weighing Scale - Forceps - 5,20 ml test tubes - observation glass Method: - Label 5 test tubes with the molarity of the sugar solutions.
- Word count: 795
Determine the energy content of different types of Seed: Compare the calorie content of different seeds.
(When the seed is used as an energy source) Risk assessment: Firstly, a lab coat should be worn in order to protect clothing from the sharp scalpel and any residue from the potato or splashes of water. The scalpel should be stored carefully and used with caution to prevent harm to the user. In order to protect the surfaces in which you cut on, use a tile whilst cutting. Water is a good conductor of electricity and spillages on electrical devices could cause electrocution. During the experiment any spillages should be mopped up quickly and entirely.
- Word count: 1452
Natural selection or "struggle for existence" as Darwin believe it, is a local process, consisting of a generation by generation adjustment to local conditions. The power of natural selection can be seen in the phenomenon of convergent evolution, in which distantly related species come to resemble one another very closely by adapting to similar ecological niches. The mollusc Littorina saxatillis is a snail species that is found on the shores around Iceland. There are usually found on rocks, under the stones.
- Word count: 1310
top, sticking to one side, small and big bubbles in between the strands, mostly clustered together DNA split up throughout the tube, not clumped together at all, flowing randomly, white pieces, thin 2 Large amount of DNA clumped together at the top, not really sticking to one side, taking up the whole circumference of the tube, small bubbles in between the DNA strands, transparent white color DNA clumped in a small amount at the top, sticking to one side of the tube, larger bubbles in between the strands, DNA breaking off into the rest of the mixture, creating a trail
- Word count: 1012
Genetically Modified Foods can cause environmental hazards, human health risks and economic concerns. The process in which food is genetically modified is entirely based on science. This process involves molecular biology and the insertion of a gene or DNA of one organism into another. There are three traditional ways in which scientists genetically modify foods. The first method of Genetic Modification is 'Selecting For Variability'. In this method, scientists choose a crop that has been naturally produced, extract the genes from this crop and insert it into other crops in order to duplicate the original crops features.
- Word count: 2955
There are two traditional methods in which doctors, with the help of scientists, perform gene therapy. The methods that the doctors used are generalized into two gene therapy techniques known as 'ex vivo' and 'in vivo' gene therapy techniques. The ex vivo gene therapy technique consists of those methods that require the cells from the affected tissue area in the patient's body to be surgically removed. The doctors then inject or splice (merge) the new DNA that will correct the disease into the affected cells and allow the cells to divide.
- Word count: 3438
This is because the increase in temperature reduces the relative humidity of air outside the leaf, therefore evaporation occurs faster. Variables Independent variable: Soil temperature Dependent variables: Rate of transpiration of Hibiscus sp Controlled variables: - Type of plant - Size of plant specimen - Light intensity - Humidity - Wind speed - Amount of water - Type of potometer - Time ASPECT 2 Controlling variables Plant Use the same type of plant for every experiment and cut them into the same size.
- Word count: 685
For few people, medicine may help reduce phenylalanine blood levels when used with a PKU diet. Although any brain or nervous system damage that develops is irreversible, problems are less likely to occur if a PKU diet commences by 3 weeks of age. 6) Fatty acids have many variations in molecular structure. One variation is in the length, or how many carbon atoms are in the molecules. Another variation is whether there are double bonds between carbon atoms in the hydrocarbon chain or not. If there is a double bond, the fatty acid is unsaturated because the number of hydrogen atoms it can bond to is reduced.
- Word count: 1731
As a result, it is expected that their theoretical offspring will have distinctive phenotypes and genotypes. It is predicted that for traits which the parents have heterozygous alleles or different genes than each other, there is a greater probability of having a more varied genotype in the offspring. Whereas, for the attributes for which the parents have homozygous alleles or equivalent genes, the number of possibilities of allele combinations in the offspring will decrease, and thus, the probability of having a varied genotype and phenotype from the parent to the offspring will also decrease.
- Word count: 1907
Amount of water through the CLEAN soil (�0.2ml) Amount of water though the DIRTY soil (�0.2ml) 0-10cm 387.5ml 408ml 10-20cm 160.0ml 854ml 20-30cm 0.5ml 171ml Rate at which water passes through each sample in each minutes Displacement from the surface of the soil taken(�1cm)
- Word count: 500
Also the treadmill is indoors with the air temperature staying at a consistent level. Hypothesis From prior background knowledge about running, I believe the runner's breathing rate will not change too much between the 12 minute mile and the 10 minute mile pace but will get faster than the breathing rate taken at rest. These two speeds are not as difficult to keep up; it is more of a fast walk. However, when the runner goes to the 8 minute pace, she will have to go through the motions of running as opposed to walking.
- Word count: 846
Now, monoclonal antibodies are antibodies which have been artificially produced against a specific antigen. They are extremely specific and bind to their target antigens. In the lab, monoclonal antibodies are produced from the clones of one cell. That's why they are called "monoclonal." This basically means that every monoclonal antibody produced by this cell is exactly the same. This gives them the collective specificity that can be used in treatment and diagnosis. Summarizing the two conceptualizations - anibodies are one of the existing mechanisms of the body that are being used to treat and diagnose disease; monoclonal antibodies are like antibodies except they are artificially produced from the clones of a single cell.
- Word count: 1185
About 20 percent is absorbed in the atmosphere. About 50 percent of the Sun's energy, largely in the form of visible light, passes through the atmosphere to reach Earth's surface. Soils, plants, and oceans on Earth's surface absorb about 85 percent of this heat energy, while the rest is reflected back into the atmosphere where absorbed by different gases including water vapor, carbon dioxide, methane, and nitrous oxide. These functions have warmed up the surface of our planet for over 4 billion years. The atmospheric gases responsible for the greenhouse effect are also known as greenhouse gases.
- Word count: 1243
Laws in Victoria Australia are the strictest in the country. Parents of surrogate (where the embryo is inserted into another women's uterus and she then carries it through the pregnancy) children were not legally considered to be the parents of the child unless they were related to the surrogate mother. Laws in Victoria also required Lesbian and single women to have medical prove that they were infertile before they were able to undergo IVF treatment. Religious views often hold a lot of controversy with IVF treatment. Many people don't believe it is up to us to "play God."
- Word count: 926
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 seen through the blue iodine solution.
- Word count: 874
5 oC -->the third room should be set at 15 oC -->the fourth room should be set at 25 oC -->the fifth room should be set at 35 oC -five small camcorders (make sure they work and have a zoom in and out function) -scooper (to collect the rat feces) -ten metal bowls -electric balance -goggles -gloves -paper and pencil **Note that the rate of digestion is equal to: temperature + (6.23 x weight in pounds) + (12.7 x height in inches)
- Word count: 698
By the use of a spectrophotometer, the percentage transmittance relative to a positive test from a control will give quantitative data to determine which method was most effective in killing the E. coli. Variables: * Independent variables: 1. For the physical methods of disinfection (boiling and UV light) the contact time to act will be changed. Time periods: 30 seconds, 2 minute and 8 minutes. 2. For the chemical methods of disinfection (sodium hypochlorite and calcium hypochlorite) the dosage, that is, the concentration will be changed.
- Word count: 837
0.2, 0.4, 0.6, 0.8 and 1.0 mol/dm3. The dependent variable is the mass of the potato cylinders before and after leaving them in the sucrose solutions. The controlled variables were the amount of solution in each test tube. Apparatus and reagents * Test tubes * Stoppers * Cork borer ( of 10mm diameter) * Metal knife * Filter papers * Forceps * Digital balance( to weigh intervals of 0.01g) * Distilled water * Sucrose solutions ( 0.2, 0.4, 0.6, 0.8, 1.0 mol/dm3) * Potato tuber Method 1)
- Word count: 917
A protein is formed by amino acids, which mRNA is coding for. When now this mRNA is expressed again into DNA, the sequence of the DNA is identified, which codes in the beginning of the chain for the certain protein. This technique is used as well in the Human Genome Project, where thousands of sequences have been identified, which code for certain proteins in the human body. The sequence of DNA is indentified so the sequence has to be separated from the DNA to be able to introduce it to the host DNA.
- Word count: 1402
Other relevant variables- concentration, size of molecules, pore size of dialysis membrane, temperature, security of bag closure. Control of Variables: using distilled water, using one solution source of starch and glucose, constant temperature, using only one type of dialysis membrane, securely tying the bag. Materials: ~20 cm dialysis tubing, ~40ml starch solution, ~ 75 ml distilled water, 200 ml beaker, scale, benedicts solution, iodine, hot plate, funnel, string. Procedure: 1. Open the dialysis tubing by running cool tap water over one edge and rubbing layers together with fingers. 2. Tie off one end securely with a piece of string.
- Word count: 959
* Light Source (colour, intensity, distance from plants) * Size of Elodea * Method of Measurement * Temperature * Equipment in Experiment * Amount of Carbon solution placed in solution Materials: * Pencil * Pen * Paper * Stopwatch * 5 Beakers * 10 test tubes (five for solutions, 5 for funnel) * Elodea plant * Water * Varying percentage of carbon solution (0.1%, 0.2%, 0.3%, 0.4%) * 2 lights * 2 funnels * Accurate scale * Tiny spoon * Test tube rack Method: 1.
- Word count: 1228
Grind grass in mortar pestle 2) Soak grass grindings in chromatography solution 3) Cut chromatography strip into about 12.5 cm 4) Draw a straight, horizontal line about 2 cm from the bottom of the strip using a pencil 5) Paint thin line of grass solution over the pencil line and let it dry under the heat lamp; repeat 5 times 6) Place chromatography paper strip in chromatography jar with about 1 cm of solution in the bottom of the jar. Make certain the line is not in the solution. 7) Allow the pigments to separate for about 15-20 minutes 8)
- Word count: 777
Evaluation: 1. Which color, other than aluminum, has the highest reflectivity? Of all the colors, red had the highest reflectivity next to aluminum. 2. Which color has the lowest reflectivity? Of all the colors, black had the lowest reflectivity. 3. What materials might give a planet a high reflectivity or albedo? Explain. Since aluminum gave the highest albedo, materials that are similar to aluminum might give a planet high reflectivity or albedo. For example, I would expect a planet containing lustrous metals to have a high albedo.
- Word count: 752