Purpose: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas).
Does caffeine affect heart rate? Purpose: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). INTRODUCTION: Caffeine is a drug that is naturally produced in the leaves and seeds of many plants. It is also produced artificially and added to certain foods. These days, caffeine is also used as flavour enhancer in wide range of cola and other soft drinks. In addition, it has medicinal use in aspirin preparations and is found in weight-loss drugs and as a stimulant in Red Bull. In humans, caffeine acts a stimulant drug, causing increased amount of stimulatory neurotransmitters to be relaxed. At high levels of caffeine consumption can lead to restlessness, insomnia and anxiety, causing raised stress level and high blood pressure. This can lead to heart and circulatory problems. Safety: . Handle glassware with care. 2. Wear a lab coat to prevent spill on fabrics. 3. The microscope is fragile and the light bulbs can get hot so handle with care. Apparatus: . Culture of Daphnia (water fleas) 2. Cavity slides 3. Dropping pipettes 4. Distilled water 5. Cotton wool 6. Standard glassware (beakers, measuring cylinders, etc.) 7. Stopwatch 8. Filter paper 9. Microscope Hypotheses: I believe that the Daphnia subjected to caffeine solution will show a rise in heart rate, this rise in heart rate will depend on the concentration of
Effect of Anaerobic Respiration On Yeast
The Effect of Temperature on the Anaerobic Respiration of Yeast Aim: To investigate the effect of temperature on the rate of respiration in a suspension of yeast Saccharomyces cerevisiae. Background Knowledge: Yeasts are a form of eukaryotic microorganisms classified in the kingdom Fungi, with approximately 1,500 species known. They reproduce asexually by budding mainly, although some species reproduce by binary fission. They are unicellular, although some species with yeast forms may become multicellular due to way in which they normally reproduce. Typically the size of a yeast cell is approximately 3-4 µm in diameter but this can vary greatly depending on the species. The yeast species Saccharomyces cerevisiae has been used in baking and fermenting alcoholic beverages for thousands of years. It is also extremely important as a model organism in modern cell biology research, and is the most thoroughly researched eukaryotic microorganism. Researchers can use it to gather information into the biology of the eukaryotic cell and human biology. These microbes are thought to be one of the first domesticated organisms. People have used yeast for fermentation and baking throughout history. Archaeologists digging in Egyptian ruins found early grinding stones and baking chambers for yeasted bread, as well as drawings of 4,000-year-old bakeries and breweries. It has many
Ethics behind selective breeding of animals
Ethics behind selective breeding of animals Selective breeding, also known as artificial selection involves identifying individuals with the desired characteristics and using them to parent the next generation. Ethical concerns and benefits of selective breeding Alongside the potential benefits, selective breeding of animals raises a variety of ethical concerns. There are two main concerns. These are: Fundamental moral objections against doing something "unnatural" or, specifically to their artificial selection, for example concerns about the consequences of reduced genetic diversity. As stated above some believe that selective breeding interferes with nature. Selective breeding has produced livestock that gives greater yields. This has given rise to a reliable cheap food source throughout the year. It could considerably raise the standard of living in developing countries where starvation is a prevalent problem. However some believe the development of new varieties should be allowed to take place naturally. We should accept a lower standard of living in return for natural breeding. When looking at this problem we should look at how useful the varieties will be in terms of helping humans. Perhaps one way forward would be to allow selective breeding only in countries where it is most needed. Many people however would take the attitude that human wellbeing is more
'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to utilise different carbon sources as substrates for cellular respiration'.
'An investigation into the ability of two strains of the yeast Saccharomyces cerevisiae to utilise different carbon sources as substrates for cellular respiration' Introduction The purpose of this investigation is to compare the ability of two different strains of yeast to respire, when using different sugars as respiration substrates. Considering the lengths that have been reached to develop varieties of yeast with greater suitability and effectiveness for very particular fermentation purposes, it seems reasonable to suppose that two different strains of the same species of yeast, selected for their different fermentation properties, have developed requirements that are not uniform. As a result of the selection and development process, yeast best suited to ferment in a given application, possess a range of different characteristics. One such characteristic may be the ability to metabolise different carbon sources at different rates. This quality is important because in each application where different respiration substrates are available, a specific strain of yeast may be required. Yeast unable to utilise the available carbon sources will have undesirable fermentation rates, and therefore may not be selected for use in that application. The two yeast here compared, have two such different applications. The first yeast from the Saccharomyces cerevisiae variety is of the
A comparative study of the density of patella vulgata (common limpet) across a sheltered shore and an exposed shore.
A comparative study of the density of patella vulgata (common limpet) across a sheltered shore and an exposed shore Aim: - To investigate the limpet density of patella vulgaris (common limpet) across a sheltered rock shore and an exposed rocky shore at the optimum niche level at both shores. Introduction: - Limpets are distinctive animals that are best known for their ability to cling onto rocks. Patella vulgata (common limpet) can be found wherever there is a rock layer firm enough for it to attach to the rocks or stones, this can be from the high shore down to the lowest part of the tide. It is abundant on all rocky shores of all wave exposure. The limpet is usually not abundant on shores where there are large growths of seaweed. The conical shell of Patella vulgata is up to 6 cm long with radiating ridges and the top central or slightly forward. Individuals from the high shore generally have a taller shell and smaller shell length when compared to juveniles and low shore animals. The outer surface of the shell is greyish white, sometimes with a yellow tint, and has crude radiating ridges and well-marked growth lines. The inner surface is smooth and greenish-grey in colour. The sole of the foot is yellowish, dull orange or brown with a grey or greenish tinge. The mantle skirt is fringed with transparent tentacles arranged in three series of different lengths,
How is ATP produced and used in living organisms?
How is ATP produced and used in living organisms? ATP (adenosine triphosphate) is required in all living cells as a continual supply of energy, to be used in processes, which keep the organism alive such as muscle contraction. ATP is made up of three main components, the base (adenine), a phosphate chain (made of three phosphate groups) and a ribose sugar backbone. The energy released from the respiration of Glucose is used to add inorganic phosphate groups to ADP to form ATP. Below is a diagram of ATP. The first step in the production of ATP and the store of energy is Glycolysis, which occurs in both aerobic and anaerobic respiration. In both cases Glycolysis takes place in the cytoplasm of the cell, because glucose is too big to get in to the mitochondria. The process starts with glucose (a six carbon sugar) and two ATP molecules needed to start off the process, (as sugars aren't very reactive) the glucose is transferred to another 6 Carbon Sugar (Fructose Bisphoshate). This breaks it down into two 3Carbon Sugars called Pyruvates. Two ATP molecules per Pyruvate is produced through the condensation reaction of a phosphate group called phosphorylation and ADP (adenosine diphosphate) forming ATP. The excess hydrogen ions are removed by the aid of NAD to form one molecule of reduced NAD per pyruvate. If the organism is anaerobic or when the supply of oxygen is not enough
The Carbon Cycle
The Carbon Cycle The Carbon Cycle is a complex series of processes through which all of the carbon in existence rotates. Carbon is an essential element which is used in life process like photosynthesises which occurs in daytime in the presence of sunlight and carbon in the gaseous form of carbon dioxide. All green plants are known as producers because they can produce their own food via the process of photosynthesis. The green plant is always the start of any food chain and is consumed by the primary consumer. Photosynthesis occurs in the green part of a plant, usually the leaf as chlorophyll is present here, were the carbon dioxide is absorbed from the atmosphere through the stomata which are pores caused by guard cell and is stored in the spongy mesophyll layer of the plant were it used alongside light and the green pigment chlorophyll which produces glucose, water and oxygen as the products of the process. The glucose is used by the plant as a food source and the water is mainly lost via transpiration to the atmosphere and oxygen is secreted by the processes of simple diffusion. Plants are autotrophic as they produce their own food. As explained above carbon dioxide is absorbed from the atmosphere into the plant for photosynthesis. Another life process which occurs in animals all the time but in plants only in night time in the absence of sun light is Respiration.
Biological Importance of Water
Biological Importance of Water: Water is a truly incredible molecule, biological life as we know it evolved from the water. It is the main constituent of all organisms and we humans are made up of around 70% of it. In order to understand why the water molecule is so important, we have to examine its structure. The Structure: A molecule of water consists of two hydrogen and one oxygen atoms (see diagram left). The atoms are joined covalently and the water molecule formed is very stable. Water is a polar molecule, and since it has two charges it is dipolar which means that it has negative ends (Oxygen) and positive ends (Hydrogen) as shown in the diagram. This dipolar quality gives an electrostatic, albeit weak, force and allows adjacent molecules to bond together resulting in water having a high boiling point. Water as a Solvent: Water is an exceptional solvent in particular when dissolving salts, simple alcohols and sugars all otherwise known as polar substances. For example an ionic salt such as potassium chloride would dissolve because the charged particles (ions) will dissociate within the water. The positive ions attract to the negative oxygen atom and the negative ions to the positive hydrogen. Substances that are non polar however, for example lipids, do not mix with water and consequently can be easily separated from aqueous solutions. For example, when droplets
In this study I will investigate the length and width of Fucus Serratus fronds found at two different zones on a rocky shore in Abbotsham, Devon, UK. I will look at an upper shore line zone and in comparison to a lower shore line to collect data from
The investigation into the length and width (morphology) of Fucus Serratus varies in different zonations from the lower and upper shore Synopsis In this study I will investigate the length and width of Fucus Serratus fronds found at two different zones on a rocky shore in Abbotsham, Devon, UK. I will look at an upper shore line zone and in comparison to a lower shore line to collect data from. Using the data that will be collected I will see whether there is a significant difference between the mean lengths and widths. Introduction This experiment will be investigating how Fucus Serratus length and width (morphology) varies with respect to different zonations along the upper and lower shore. The research will be conducted along Abbotsham rocky shore in Bideford, Devon. This specific location has been allocated as it has varied abiotic conditions such as pH, temperature, humidity and water salinity. These various aspects lead to the belief that there will be a diverse selection of species available. Null Hypothesis There will be no significant difference between the different zonations and the width and length (morphology) of Fucus Serratus fronds. Variables Dependant variables are the things I will be measuring, such as: - The length and width of Fucus Serratus fronds; To measure the length of the fronds, a measuring tape will be used. The units for the
Tuberculosis and its treatment
Tuberculosis Introduction T uberculosis (TB) is an infectious disease that is caused by several species of Mycobacterium, collectively called the tubercle bacillus. The bacillus is a small, rod shaped bacterium that is extremely hardly; it can survive for months in state of dryness and can also resist the action of mild disinfectants. Tuberculosis is a contagious disease. Like the common cold it spreads through the air. Only people who are side with pulmonary tuberculosis are infectious when infectious people cough, sneeze, talk or spit, they propel TB germs, known as bacilli, into the air. A person needs only to inhale small number of theses to be infected. The tubercle bacillus was discovered and identified as the cause of tuberculosis in 1882 by the German physician Robert Koch. Tuberculosis occurs in humans worldwide, and in many developing countries it is still cause of death. The disease reached near epidemic proportions in the rapidly urbanizing and industrializing societies of Europe and North America in the 18th and 19th centuries. Indeed, tuberculosis was the leading cause of death for all age groups in the western world from that period until the early 20th, at which time improved health and hygiene caused a gradual but continuing decline in its mortality rates. New cases of TB worldwide roughly correlate with economic conditions: the highest
