Saturday, January 25, 2020

The Effect Of Temperature On Permeable Membranes Biology Essay

The Effect Of Temperature On Permeable Membranes Biology Essay The aim of this experiment was to determine what effect an increase in the surrounding temperature has on the selectively permeable membranes of plant cells, e.g., red cabbage (Lane, 2010a). The cell membrane is the fluid-mosaic model. The proteins are embedded in the cell membrane. The lipid exists as a phospholipid bilayer form. The hydrophobic which mean water hating portions of the lipid molecule face the inside while the hydrophilic which mean water loving parts face either the cytoplasm or extracellular aqueous environment. The protein molecules are of two types in the membrane. Internal proteins are embedded in the phospholipid bilayer which enhance the membranes shape, providing passageways for the movement of substances through the membrane while the peripheral proteins are attach to the surface of membrane and are easier to extract (Losos, Manson and Singer, 2008) The purpose of a cell membrane is to controls what enters and exits the cell. It acts as a selective barrier between the internal and external fluid that means the cell membrane to be selectively permeable. This process supplies the cell with useful material and removes waste products. Normally, this is done by active or passive transportation. The passive transportation allows substances to move from high concentration to low concentration without energy required. The active transportation carries substances such as ions and glucose from low concentration to the high concentration, requiring energy and a carrier to support (Losos, Manson and Singer, 2008). Figure 2 (Adapted from Garland, 2004) shows the process of transportation through the cell membrane Figure 2: Transportation through the Membrane (Adapted from Garland, 2004) Certain conditions can damage the cell membrane. For instance, high temperature leads to violent collisions that can destroy a membrane. There is a hypothesis that an increase in temperature denatures the membrane and causes the substances within the membrane to leak out (Answers, 2010). The high temperature can make the cell membrane more permeable and allow it to be more prone to leakage. Red cabbages are used as a model to investigate how the temperature affects the selectively permeable membranes. Red cabbages contain a large mount of a water-soluble red pigment called anthocyanin, which is located in the vacuole and unable to pass through the tonoplast membrane. If these cells are affected by changes in temperature, the integrity of the cell membrane becomes damaged. As a result, anthocyanin which as antioxiants and protects cell from oxidative damage can leak out of the cells and into the surrounding water. The extent of damage to the cell membrane is directly associated to the intensity of red color and it would appear in the water surrounding the red cabbage (Manhattan, 2009). Method Apparatus 7 test tubes Test tube rack Cork borer Scalpel Tile Small beaker Mounted needle Large beaker Thermometer Burner (Lane, 2010b) Firstly, a leaf of red cabbage tissues was cut into 42 discs of the same size (approximately 1mm wide) by a cork borer. 42 red cabbage discs were placed in a small beaker and were washed. 7 test tubes were labelled 30à ¢Ã¢â‚¬Å¾Ã†â€™, 40à ¢Ã¢â‚¬Å¾Ã†â€™, 50à ¢Ã¢â‚¬Å¾Ã†â€™, 60à ¢Ã¢â‚¬Å¾Ã†â€™, 70à ¢Ã¢â‚¬Å¾Ã†â€™, 80à ¢Ã¢â‚¬Å¾Ã†â€™ and 100à ¢Ã¢â‚¬Å¾Ã†â€™. The first two test tubes which labelled 30à ¢Ã¢â‚¬Å¾Ã†â€™, 40à ¢Ã¢â‚¬Å¾Ã†â€™ and approximately 6 cm3 cold water was added using a measuring cylinder. The remaining test tubes had 6 cm3 cold water added to each. Meanwhile, a water bath was prepared using a large beaker, tripod and gauze. The 7 test tubes with 6 cm3 water were heated in the water bath. A thermometer was placed into each test tube to measure the temperature. 6 red cabbage discs were impaled on a mounted needle with space between each disc. When the water inside the test tube labelled 30à ¢Ã¢â‚¬Å¾Ã†â€™ reached 30à ¢Ã¢â‚¬Å¾Ã†â€™ temperature, the burner was removed a nd 6 discs on the needle was placed in the test tube for exactly 1 min then the test tube was removed from the water bath. The disks were left in this tube. When the water inside the test tube labelled 40à ¢Ã¢â‚¬Å¾Ã†â€™ reached 40à ¢Ã¢â‚¬Å¾Ã†â€™ temperature, the above procedure was repeated. The test tube labelled 50à ¢Ã¢â‚¬Å¾Ã†â€™ reached the temperature. All the procedures were restarted according to the guide. To all the test tubes were added 6 cm3 cold water and a water bath was prepared using a large beaker, tripod. When the water was heated gently to 30à ¢Ã¢â‚¬Å¾Ã†â€™, the burner was removed and the 6 red cabbage discs on an impaled needle were placed in the water bath for exactly 1 minute. The discs was pushed off and dropped into the test tube labelled 30à ¢Ã¢â‚¬Å¾Ã†â€™. The procedure was repeated for the other tubes. From 40 °to 90 °C, all the procedures in own water bath. For 100à ¢Ã¢â‚¬Å¾Ã†â€™ the discs, needle were placed in others water bath with the temperature at 100à ¢Ã¢â‚¬Å¾Ã†â€™ for 1 minute, then the discs were pushed off and dropped into the test tube labelled 100à ¢Ã¢â‚¬Å¾Ã†â€™. The discs in the test tube s were left for 20 minutes and then the tubes were shaken and compared. Result Temperature /à ¢Ã¢â‚¬Å¾Ã†â€™ Observation 30 The 6 red cabbage discs were still purple and unchanged the water was still colourless. 40 The colours of the 6 red cabbage discs were remained and unchanged purple and the water was still clear. 50 The colours of 6 red cabbage discs were a little faded and the water became a little purple. 60 The colours of 6 red cabbage discs were faded lighter purple more than 50à ¢Ã¢â‚¬Å¾Ã†â€™ and the colour of water changed from colourless into light purple. 70 The colours of 6 red cabbage discs were faded more than 60à ¢Ã¢â‚¬Å¾Ã†â€™ and the colour of water changed from transparent into a light blue. 80 The colours of 6 red cabbage discs were very faded than 70à ¢Ã¢â‚¬Å¾Ã†â€™ and the colour of water changed from transparent into a light green. 100 The colours of 6 red cabbage discs changed from purple into white and the colour of water was strongly changed from transparent into green. Table 1: Heating the Red Cabbage Discs Discussion Table 1 shows clearly that an increase temperature on the red cabbage fades the purple of these discs and they become more and more faded while the colour of the surrounding water inside the test tube becomes darker and darker. This phenomenon purple-blue-green result from that the red cabbage dices have permeable membranes losing the permeability of their cell membranes. If the temperature goes against what the membranes can withstand, the permeability of membranes increases as the protein becomes denatured, the lipid parts of membranes liquefies and the proteins create holes in the fabric, and the membranes fall apart. The high temperature produces an increase in kinetic energy that makes atoms in the protein to vibrate and move more breaking hydrogen and ionic bonds in protein molecules and changing the 3D shape of the system. These proteins are unable to translate substances in and out of the membrane. All the factors lead to the anthocyanin leaking out of the membranes producing a colour in the water surrounding the red cabbage cells (Erik, 2002). The results of investigating the effect of temperature on permeable membranes are largely as predicted. There were several variables that controlled this experiment to make sure the results were comparable. The first major key variable was the size of red cabbage discs. The red cabbage tissue was cut into discs which were used to ensure accuracy by increasing precision in the volume of water. The cylinders should be same for all experiments because the volume of water affected the concentration of the pigment. The second variable was allowing enough time (20 minutes) for colour to be seen. All the test tubes should be left the same and enough time for observations after putting the red cabbage discs into the test tubes. Time altered the effect of the experiment; some tubes had a longer effect than others, more of the pigments in the red cabbage cells will leak out and the pigments in the surrounding water. All the material should be washed very thoroughly after cutting. This process made the experiment more highly accurate, because using water to wash the material meant that impurities were minimised. Possible errors may have arisen during this experiment. Firstly, the procedure at the beginning of the experiment was not correctly followed according to the instructions (Lane, 2010c). For instance, 6 cm3 cold water was measured not accurate, the red cabbage leaf did not wash under running water and using another water bath which resulted from the instruction had not been read carefully and seriously. Secondly, the phenomenons purple-blue-green in this test was a little different from the theory that as the temperature increases, the colour of the surrounding water will become darker (Lane, 2010d). This may stem from much of the red pigment escaping from the discs while heating the red cabbage in the beaker. The result of the higher temperature may have affected this more as a lot of the pigment has already leaked out into the beaker. Another reason may be the concentration of pigment leading to change the stability of the pigment molecule. Thirdly, the time was not sufficient for r epeating the experiment, which made the results less accurate. A future experiment should be improved in follow ways. The instruction should be read carefully and thoroughly, so the experiment can go on logical. Secondly, the temperature should be checked at the start of when the red cabbage was put in the water and at the end of the last minute using a thermometer to maintain the temperature of the heated water. Thirdly, a colorimeter should be provided to measure the amount of light absorbed by solution of each reaction temperature. The higher concentration of anthocyanin means a higher reading on the colorimeter. Fourthly, the experiment should be repeated more times to make sure the results were not obtained by chance or by external factors. In addition, the effect of cooler temperature even under 0à ¢Ã¢â‚¬Å¾Ã†â€™ could be tested to observe if the membrane is broken down in a similar way. Conclusion It can be concluded that as the temperature was increased, more of the red pigment leaked out of the permeable membrane. The permeability of the membrane in red cabbages can be damaged by high temperature.

Friday, January 17, 2020

Ensuring People Support for Education and Training Programs Essay

A collaborative effort is a key to success in the field of continuing education.   That is to maintain partnership with the learners, the supervisors and, the managers.   To ensure support from each participant it is important that there is connectivity before, during, and after the training program.   After all, learning is effective when it is applied as well as teaching is assimilated when it is explained. In Cafarella’s book, the five primary purpose of education was explicitly stated that is; â€Å"to encourage growth, to assist with practical problems, to prepare people for current and future opportunities, to assist with change for desired results, and to examine community or social issues (Schultz, 2002).†   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Educators are tasked to elaborate from the beginning the reason of the training program and if it is presented to learners as useful and not mandatory support from the learner is ensured even from the start of the program.   Key people or the supervisors can be invited in the planning process so that they can tell the planner or the educator actual experiences on how the knowledge will be applied.   Also it is best to include the supervisors in giving decisions on when is the training program be scheduled so that critical schedule in their operations will not be hampered.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   During trainings learners should get involved in the discussion by inviting them to give examples and with those actual situations mentioned by the participants, trainers should help the learner to reflect on the subject and how it could be applied.   Supervisors at the same time can be asked to mentor or assist in the on-going program.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Training program does not end at the venue but probing whether the learning process is blocked after instruction was given ensures effectiveness of the course.   Learners should be encouraged to help one another and evaluate the learning process.   Supervisors should be asked on the feedback if the course has been effective by checking if what is learned was applied in each participants actual work situation.   To ensure continuous support and partnership, endings should be addressed whether it is positive or negative (Caffarella, 2002).   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Managers are tasked to implement goals and objectives; they are the one who manage change.   To ensure their support from beginning to end, they should be asked to provide consultations before and after.   They should be convinced that the program is helping their organization to grow. References Schultz, J. D. (2002). Book Review: Planning Programs for Adult Learners, 2nd Edition by Rosemary A. Caffarella [Electronic Version]. Retrieved 12 February 2008 from http://www.exchangesjournal.org/reviews/review_1107.html. Caffarella, R.A. (2002).   Planning Programs for Adult Learners (Chapter 5), 2nd Edition, 403 pages ISBN: 0-7879-5225-7.

Thursday, January 9, 2020

Solar Energy The Ultimate Renewable Energy Resource Essay

The current use of fossil fuels as our main energy source has two drawbacks: their inevitable depletion and the pollution associated with combustion. These two drawbacks in addition to the growing concern of global warming has pushed for the development of more sustainable sources of energy, namely solar energy and its derivatives (i.e. wind power). Solar energy is appealing for its potential to meet all our demands, while proving to be a pollution free resource.(Bohn, 2009) Solar energy originates from the thermonuclear fusion reactions occurring in the sun. Leaving all the byproducts of the reactions behind in the sun, the energy that reaches the Earth is pure radiant energy. This energy represents the entire electromagnetic†¦show more content†¦The clouds absorb 10% off the energy, while reflecting about 25%, and allow about 17% to pass through. The atmosphere absorbs 9%, reflects 9%, and transmits 6% of the solar energy. Twenty-four percent of the solar energy directly reaches the ground. Overall, about 47% (17+6+24) of the sun’s energy striking the Earth reaches the ground, where it is collectable by solar devices. These devices are used generally for two purposes: to heat water and/or living spaces and to produce electricity. Solar energy is used to heat water for homes and buildings. Two methods used to accomplish this are the passive system, which has no moving parts and strictly relies on the convection currents, and an active system which uses pumps to move the liquid. In both systems, a solar device called a flat bed collector absorbs the sun’s energy to heat the water. The collector consists of a thin, broad box with a glass or clear plastic top and a black bottom with water tubes embedded in it. The black bottom allows for the maximum amount of heat absorption while the clear cover and interior insulation prevent heat loss. As water is heated in the pipes it rises up to a storage tank where it can then be sent throughout the house for consumption. Cooler water moves into the pipes and forms a convection cycle or current. In the active system, antifreeze is used as the fluid instead of water so it remains a liquid if the outside temperature drops below freezing. Also, a heatShow More RelatedSolar Energy : The Ultimate Renewable Resource Manish Kumar1264 Words   |  6 PagesSOLAR ENERGY IS THE ULTIMATE RENEWABLE RESOURCE   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚     Manish Kumar (EE B.Tech)   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Universal Institute of Technology, Garhi (Hisar)   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã ‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  manishboora13@gmail.com       Abstract-The energy availability is essentially needed for all living beings in life .TheRead MoreNew And Alternative Sources Of Energy1311 Words   |  6 Pages Today s society uses enormous amounts of energy. *The shadow of our presence on this planet is a result of generations upon generations of production and utilization of energy*. 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This led to a de crease in economic activity that reflected as a decrease in the demand for energy in the form of oil. Alternative energy sources needed to be considered in order to maintain the economic activities of society without further depleting the natural resources. Besides these crises inRead MoreThe Current Demand For Energy1224 Words   |  5 PagesEurope experienced two energy crises during the 1970s, which led to escalating demand for energy resources (specifically, oil) that could not be adequately supplied (Bonny, 1987; Donatos Mergos, 1989). This led to a decrease in economic activity that reflected as a decrease in the demand for energy in the form of oil. Alternative energy sources needed to be considered in order to maintain the economic activities of society without further depleting the natural resources. Besides these crises inRead MoreThe Current Demand For Energy1238 Words   |  5 PagesEurope experienced two energy crises during the 1970s, which led to escalating demand for energy resources (specifically, oil) that could not be adequately supplied (Bonny, 1987; Donatos Mergos, 1989). This led to a decrease in economic activity that reflected as a decrease in the demand for energy in the form of oil. Alternative energy sources needed to be considered in order to maintain the economic activities of society without further depleting the natural resources. Besides these crises inRead MoreThe Cost Of Fossil Fuels1147 Words   |  5 PagesEnergy Policy Sheldon Fogle Telescope to Microscope April 22, 2015 Global Crisis Our species as a whole is very successful in many advancements such as technology, in society all together, and just overall in life but, currently we are failing our environment. Since our world is an immense place that consumes so much energy our demand is high. 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Wednesday, January 1, 2020

Ten Facts About Cells and Cell Function

Cells are the fundamental units of life. Whether they be unicellular or multicellular life forms, all living organisms are composed of and depend on cells to function normally. Scientists estimate that our bodies contain anywhere from 75 to 100 trillion cells. In addition, there are hundreds of different types of cells in the body. Cells do everything from providing structure and stability to providing energy and a means of reproduction for an organism. The following 10 facts about cells will provide you with well known and perhaps little known tidbits of information about cells. Key Takeaways Cells are the basic units of life and are very small in size, ranging from approximately 1 to 100 micrometers. Advanced microscopes allow scientists to be able to see such small entities.There are two major types of cells: eukaryotic and prokaryotic. Eukaryotic cells have a membrane bound nucleus while prokaryotic cells do not have a nucleus that is membrane bound.A cells nucleoid region or nucleus contains the cells DNA (deoxyribonucleic acid) which contains the cells encoded genetic information.Cells reproduce by different methods. Most prokaryotic cells reproduce by binary fission while eukaryotic cells can reproduce asexually or sexually. Cells are too Small to be Seen Without Magnification Biologists are able to obtain detailed observations of cells with microscopes. PeopleImages / E / Getty Images Cells range in size from 1 to 100 micrometers. The study of cells, also called cell biology, would not have been possible without the invention of the microscope. With the advanced microscopes of today, such as the Scanning Electron Microscope and Transmission Electron Microscope, cell biologists are able to obtain detailed images of the smallest of cell structures. Primary Types of Cells Eukaryotic and prokaryotic cells are the two main types of cells. Eukaryotic cells are called so because they have a true nucleus that is enclosed within a membrane. Animals, plants, fungi, and protists are examples of organisms that contain eukaryotic cells. Prokaryotic organisms include bacteria and archaeans. The prokaryotic cell nucleus is not enclosed within a membrane. Prokaryotic Single-Celled Organisms were the Earliest and Most Primitive Forms of Life on Earth Prokaryotes can live in environments that would be deadly to most other organisms. These extremophiles are able to live and thrive in various extreme habitats. Archaeans for example, live in areas such as hydrothermal vents, hot springs, swamps, wetlands, and even animal intestines. There are More Bacterial Cells in the Body than Human Cells Scientists have estimated that about 95% of all the cells in the body are bacteria. The vast majority of these microbes can be found within the digetive tract. Billions of bacteria also live on the skin. Cells Contain Genetic Material Cells contain DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), the genetic information necessary for directing cellular activities. DNA and RNA are molecules known as nucleic acids. In prokaryotic cells, the single bacterial DNA molecule is not separated from the rest of the cell but coiled up in a region of the cytoplasm called the nucleoid region. In eukaryotic cells, DNA molecules are located within the cells nucleus. DNA and proteins are the major components of chromosomes. Human cells contain 23 pairs of chromosomes (for a total of 46). There are 22 pairs of autosomes (non-sex chromosomes) and one pair of sex chromosomes. The X and Y sex chromosomes determine sex. Organelles Which Carry Out Specific Functions Organelles have a wide range of responsibilities within a cell that include everything from providing energy to producing hormones and enzymes. Eukaryotic cells contain several types of organelles, while prokaryotic cells contain a few organelles (ribosomes) and none that are bound by a membrane. There are also differences between the kinds of organelles found within different eukaryotic cell types. Plant cells for example, contain structures such as a cell wall and chloroplasts that are not found in animal cells. Other examples of organelles include: Nucleus - controls cell growth and reproduction.Mitochondria - provide energy for the cell.Endoplasmic Reticulum - synthesizes carbohydrates and lipids.Golgi Complex - manufactures, stores, and ships certain cellular products.Ribosomes - involved in protein synthesis.Lysosomes - digest cellular macromolecules. Reproduce Through Different Methods Most prokaryotic cells replicate by a process called binary fission. This is a type of cloning process in which two identical cells are derived from a single cell. Eukaryotic organisms are also capable of reproducing asexually through mitosis. In addition, some eukaryotes are capable of sexual reproduction. This involves the fusion of sex cells or gametes. Gametes are produced by a process called meiosis. Groups of Similar Cells Form Tissues Tissues are groups of cells with both a shared structure and function. Cells that make up animal tissues are sometimes woven together with extracellular fibers and are occasionally held together by a sticky substance that coats the cells. Different types of tissues can also be arranged together to form organs. Groups of organs can in turn form organ systems. Varying Life Spans Cells within the human body have different life spans based on the type and function of the cell. They can live anywhere from a few days to a year. Certain cells of the digestive tract live for only a few days, while some immune system cells can live for up to six weeks. Pancreatic cells can live for as long as a year. Cells Commit Suicide Cell Apoptosis. Dr_Microbe / iStock / Getty Images Plus When a cell becomes damaged or undergoes some type of infection, it will self destruct by a process called apoptosis. Apoptosis works to ensure proper development and to keep the bodys natural process of mitosis in check. A cells inability to undergo apoptosis can result in the development of cancer. Sources Reece, Jane B., and Neil A. Campbell. Campbell Biology. Benjamin Cummings, 2011.