autodirigidas
Universidad de Buenos Aires Facultad de Ciencias Exactas y Naturales Licenciatura en Cs. Biológicas Int. Güiraldes 2620 Ciudad Universitaria - Pab. II, 4º Piso CPA: C1428EHA Ciudad Autónoma de Buenos Aires ARGENTINA. ?: +54 11 4576-3349 ? Fax: +54 11 4576-3384 Conmutador: 4576-3300 Int.: 206 http://www.bg.fcen.uba.ar Carrera: Licenciatura en Ciencias Biológicas Código de la carrera: 05 Código de la materia: CARÁCTER: [SI / NO] PUNTAJE: Curso obligatorio de licenciatura (plan 1984) NO -- Curso optativo de licenciatura (plan 1984) SI -- Duración de la materia: 6 Semanas Cuatrimestre en que dicta: 2º Cuatrimestre Frecuencia en que se dicta: ANUAL Horas de clases semanales: Discriminado por: Hs. Teóricas 6 Problemas _ Laboratorios 6 Seminarios 2 Carga horaria semanal: 4 Carga horaria total cuatrimestral: 224 Asignaturas correlativas: Genética I - Física II Forma de Evaluación: 2 parciales teórico- práctico. Exámen final Profesor/a a cargo: Dr. Dante Agustín PAZ Firma y Aclaración: Fecha: / / DEPARTAMENTO DE BIODIVERSIDAD Y BIOLOGÍA EXPERIMENTAL FACULTAD DE CIENCIAS EXACTAS Y NATURALES UBA BIOLOGÍA CELULAR Objetivos de la asignatura. Proporcionar al alumno el conocimiento de los métodos de estudio aplicables para el conocimiento de la estructura y función de las
The comparison of bacterial content in a range of milks.
Yasmin White 1210 The comparison of bacterial content in a range of milks Introduction Milk is a nutritious food. It is an excellent source of calcium, phosphorus, riboflavin, and vitamin D and a good source of protein, vitamin A, potassium, and several B vitamins. These constituents differ widely in molecular size and solubility, therefore milk is a complex physiochemical system. The enzymes found in cow's milk are: protease, amylase, lactase, lipase, xanthine oxidase, phosphatase, aldolase, catalase, and peroxidase. It's the lipase here that can cause hydrolytic rancidity. The smallest molecules, those of salts, lactose, and water-soluble vitamins, are in 'true solution'. The proteins, including the enzymes, are in the colloidal state (suspension in the liquid) because of the large size of their molecules. Lactose (milk sugar) is a white crystalline disaccharide, it has the same molecular formula as sucrose (C12H22O11) but it differs in structure, making it an isomer. It contains the simple sugars, glucose and galactose. Galactose is catalysed by lactase. When milk sours, the lactose is converted by bacteria to lactic acid, this causes a change in the milk's consistency. Milk is often naturally contaminated with bacteria. Lactobacillus and Streptococcus Lactis (the two most common lactic acid bacteria) produce lactic acid during fermentation: Bacteria: Bacteria are
Find out how the rate of hydrolysis of an organic halogen compound depends on the identity of the halogen atom, and the nature of the carbon-hydrogen 'skeleton'.
PLANNING AIM: The purpose of this experiment is to find out how the rate of hydrolysis of an organic halogen compound depends on the identity of the halogen atom, and the nature of the carbon-hydrogen 'skeleton'. I will be comparing the rates of hydrolysis of the primary substances 1-chlorobutane, 1-bromobutane, 1-iodobutane, and will investigate the rate of hydrolysis of the tertiary substance 2-bromo-2-methylpropane. From the results I will then go on to deduce a rate expression/equation and a possible mechanism for the reaction. Calculations that are to be carried out include that of gradients and rates of the graph. This is needed because the gradient of the graph gives us the rate of reaction. A rate for each tangent taken needs to be worked out so that a rate graph can be constructed, which will give the order of the hydrolysis of the haloalkane. Example: Figure 1 (I) Rate = Gradient Gradient = Y2 - Y1 X2 - X1 = [reactants at Y2] - [reactants atY1] (where [ ] refers to the concentration) t2 - t1 (where t refers to the time) Rate = ?[reactants] (where ? refers to the change) ?t The initial rate will be taken, therefore the gradient line will start at
Effect Of Substrate Concentration On The Activity Of Catalase
Effect Of Substrate Concentration On The Activity Of Catalase Effect Of Substrate Concentration On The Activity Of Catalase AIM This is an experiment to examine how the concentration of the substrate hydrogen peroxide affects the rate of reaction of the enzyme catalase. PREDICTION I predict that as the substrate concentration increases, the rate of reaction will go up at a directly proportional rate until the solution becomes saturated with the substrate hydrogen peroxide. When this saturation point is reached, then adding extra substrate will make no difference. The rate steadily increases when more substrate is added because more of the active sites of the enzyme are being used which results in more reactions so the required amount of oxygen is made more quickly. Once the amount of substrate molecules added exceeds the number of active sites available then the rate of reaction will no longer go up. This is because the maximum number of reactions are being done at once so any extra substrate molecules have to wait until some of the active sites become available. BACKGROUND INFORMATION Enzymes such as Catalase are protein molecules which are found in living cells. They are used to speed up specific reactions in the cells. They are all very specific as each enzyme just performs one particular reaction. Catalase is an enzyme found in food such as potato and liver. It
The effects of organic effluent from the seweage on the biodiversty in a freshwater stream.
AIM: The aim of this investigation is to find out the effects of organic effluent from the seweage on the biodiversty in a freshwater stream. This will be done by looking at biotic(such as food supply, competition and predation) and abiotic factors (such as oxygen concentration in water, light and nitrate levels in the water) neccessary for the servival of most sea organisms. Biotic index will be used to determine levels of organic effluent from the seweage in the fresh water stream and Diversty index will be obtained to see how diverse species are in a given area of the stream according to the levels of organic effluent present.The areas selected will be at random and they will be selected by considering all the health and safety measures when I reach the fresh water stream.This method will ensure that the results obtained are reliable. I will back up my results for the biotic index and the diversty index by carrying out BOD, light and nitrate levels test for the abiotic factors so that the biodiversty of selected areas can be explained by taking into consideration the various levels of organic effluent. BACKGROUND RESEARCH: Water is vital for the existance of life. The man uses water for various reasons. e.g. 1. Used for drinking and for domestical livestock. 2. Seweage is removed by water. 3. It is used to irrigate crops. 4. It has industrial uses e.g a coolant
An in Investigation into the Resistance of a Wire.
An in Investigation into the Resistance of a Wire Aim: To investigate the factors affecting resistance There are four main factors which affects the resistance and they are: > The material > The cross-sectional area (thickness) > The length > The temperature But in this investigation I am only going to investigate in the factors length and cross sectional area Background Information Electricity cannot be seen but you can see the effect electricity has. It can: > Make things hot-as in the heating element of an electric fire > Make things magnetic-as in an electromagnet > Produce light-as in a light bulb > Break down certain compounds and solution-as in electrolysis In a nutshell, electricity is very good at transferring energy. To understand this, a simple model of what happens in electrical circuits can help. If an electrical circuit is made using a battery and a lamp, the battery can be thought of as pushing electrical charge round the circuit to make a current. The battery also transfers energy to the electrical charge. The voltage of the battery is a measure of how much 'push' it can provide and how much energy it can transfer to the charge. Scientists now know that electric current is really a flow of electrons. The electrons actually flow around the circuit from negative to positive. Unfortunately, although early scientists knew that there must be
Human biology short notes
Name of organelle Structure Function Cell membrane Composed of mainly proteins and lipids Forms the outer boundary of the cell Partially permeable (Selective)- has special pores Controls the transfer of substances into and out of the cell Prevents cell contents from escaping or mixing with the neighboring cells medium Cytoplasm Structure less, semi- fluid, jelly like substance Provides a medium for chemical reactions Suspends organelles within the cell Nucleus Spherical body Contains a nucleolus Neucleoplasm suspends chromatin Nuclear membrane contain special pores Controls cellular activities Contains chromosomes responsible for cell division Plastids *Chloroplast (Only in Plant Cells) Colourless plastids contain starch (used as a food store) Plastids which contain a green pigment- chlorophyll are called chloroplast Chlorophyll present absorbs the energy from the sunlight and uses it for photosynthesis in plants Cell wall (Only in Plant Cells) Made up of mainly cellulose Forms the outer boundary of the plant cell Not selective Non-living Keeps the rigid structure of the cell Since it is not selective allows any dissolved substances to pass through Mitochondria Doubled membrane- inner membrane is highly folded to increase the surface area Responsible for generating energy for cellular activities Aerobic
Investigating the amazingness of theBouncing Ball!
Physics A2 Coursework Investigating the amazingness of the Bouncing Ball! In this investigation I will lead you through my experiments and findings on the decaying bounce of balls. From this investigation I want to have worked out the effect of temperature change on the decaying bounce of a ball. However, at first I will have to choose suitable variables for this experiment. First of all I had to distinguish a method for measuring the heights reached by the bouncing ball. My initial idea was to have a white ball bounce against the backing of a grided black board, so as the ball bounced I'd mark out where the ball bounces. Using a light gate the second time, I'd make sure that the ball did indeed reach that point. However, the ball wouldn't bounce to the exact same height every time, as the ball may bounce sideways and so the height reached would change. Where I mark out the height depends on my eye level and how quick I am to mark out this height may be delayed by i.e./ how tired I am at the time. This method is very prone to error. Another method that may have worked would be to have metal claws, interlocking however not making contact ie. like a grid, but with a charge running through them. A metal or a ball wrapped with tin foil or just a thin layer of metal on the outside of a ball would be bounced onto this grid. Each time the metal plated ball bounces
The role of mass customization and postponement in global logistics
The role of mass customization and postponement in global logistics "Mass Customisation is - the customisation and personalisation of products and services - for individual customers at a mass production price. So, what does mass customisation mean for manufacturers and retailers? Simply this, that there's money to be made and customer satisfaction to be achieved by allowing the buyer to customise his or her own purchases by choosing the size, colour and style from a predetermined, often extensive, list of 'options'. The ultimate goal is to manufacture on a mass scale, retain or improve the margins associated with mass production, and supply a final product that meets each buyer's individual desires. Apparel captures a major share of mass-customised products, but the concept stretches far beyond a single industry - to furniture, automobiles, eyeglasses, aeronautics, Barbie dolls, computers and so on. For the manufacturer, mass customisation offers an advantage because it differentiates his product from that of his competitors. It enables him to charge a premium for allowing his customer the 'privilege' to specify the final details of his purchase. Moreover, it allows the consumer to 'buy in' emotionally to the purchase, thereby reducing the risk that he will return the product he's purchased - forcing the manufacturer to restock or mark down, or even worse scrap, the
To investigate how the length (mm) and the cross-sectional (mm2) area of a wire affects its resistance (ohms).
GCSE COURSEWORK PHYSICS : RESISTANCE OF A WIRE Coursework Coursework Owner : Abu Shoaib Date Submitted : 7 November 2003 Form : 5A TABLE OF CONTENTS . PLAN 3 .1. Aim: 3 .2. Background knowledge: 3 .3. Apparatus: 3 .4. Safety: 4 .5. Variables: 5 .5.1. RESISTANCE (OF ENTIRE CIRCUIT) 5 .5.2. RESISTANCE (OF RHEOSTAT) 5 .5.3. LENGTH 5 .5.4. CROSS-SECTONAL AREA 6 .5.5. SUBSTANCE 8 .5.6. TEMPERATURE 8 .6. Observations to be made: 9 .7. Theory: 10 .8. Method: 12 .9. Prediction: 13 .9.1. LENGTH: 14 .9.2. CROSS-SECTIONAL AREA: 14 .10. Variables table: 15 .11. Preliminary work: 15 2. OBTAINING EVIDENCE 16 2.1. Preliminary Results: 16 2.1.1. LENGTH: 16 2.1.2. CROSS-SECTIONAL AREA: 16 2.2. Length: 17 2.3. Cross-sectional area: 19 3. ANALYSIS 21 3.1. THEORY/HYPOTHESES: 21 3.2. LENGTH: 22 3.3. CROSS-SECTIONAL AREA: 23 3.4. CONCLUSION: 24 4. EVALUATION 26 4.1. LENGTH: 26 4.2. CROSS-SECTIONAL AREA: 28 4.3. OVERALL EVALUATION: 29 5. EXTENSION PLAN 30 5.1. Aim: 30 5.2. Apparatus: 30 5.3. Safety: 31 5.4. Theory: 31 5.5. Prediction: 33 6. GRAPHS 34 - 68 . PLAN .1. Aim: To investigate how the length (mm) and the cross-sectional (mm2) area of a wire affects its resistance (ohms). .2. Background knowledge: Electricity, or more specifically, the flow of electrons carrying an electrical charge through a metallic conductor is known as an
