The Effects of Light Intensity on the Growth Rates of Green Algae

We used to florets from the cauliflower and disrupted the cell walls using a cold isolation buffer (0.3 M D-mannitol, 0.02 M phosphate buffer, pH 7.2) and an abrasive, we then strained the homogenate with cheesecloth into a centrifuge tube suppoerted by ice. The homogenate was then centrifuged at 600 g for 10 minutes at 4⁰C. The postnuclear supernatant was removed and centrifuged at 12,000 g for 30 minutes at 4⁰C. The post mitochondrial supernatant was removed and the mitochondrial pellet was resuspended in a cold assay buffer (0.3 M D-mannitol, 0.01 M KCl, 0.005 M MgCl₂, 0.02 M phosphate buffer, pH 7.2). Both samples were stored at

Introduction: Photosynthesis can be defined as a solar powered process that removes atmospheric carbon dioxide and transforms it into oxygen and carbohydrates (Harris-Haller 2014). Photosynthesis can be considered to be the most important biochemical process on Earth because it helps plants to grow its roots, leaves, and fruits, and plants serve as autotrophs which are crucial to the food chain on earth. Several factors determine the process of photosynthesis. Light is one these factors and is the main subject of this experiment. The intensity of light is a property of light that is important for photosynthesis to occur. Brighter light causes more light to touch the surface of the plant which increases the rate of photosynthesis (Speer 1997). This is why there is a tendency of higher rates of photosynthesis in climates with a lot of sunlight than areas that primarily do not get as much sunlight. Light wavelength is also a property of

The role of an enzyme is to catalyse reactions within a cell. The enzyme present in a potato (Solanum Tuberosum) is catechol oxidase. In this experiment, the enzyme activity was tested under different temperature and pH conditions. The objective of this experiment was to determine the ideal conditions under which catechol oxidase catalyses reactions. In order to do this, catechol was catalyzed by catechol oxidase into benzoquinone at diverse temperatures and pH values. The enzyme was exposed to its new environment for 5 minutes before the absorbance of the catechol oxidase was measured at 420 nm using a spectrophotometer. The use of a spectrophotometer was crucial for the collection of data in this experiment. When exposed to hot and cold temperatures, some enzymes were found to denature causing the activity to decrease. Similarly, when the pH was too high or low, then the catechol oxidase enzyme experienced a significant decrease in activity. It can be concluded after completing this experiment that the optimal pH for catechol oxidase is 7 and that the prime temperature is 20º C. Due to the fact that the catechol oxidase was only tested under several different temperatures and pH values, it is always possible to get a more precise result by decreasing the increments between the test values. However, our experiment was able to produce accurate results as to the

When using algae beads and a CO2 indicator, the process of Photosynthesis and Cellular Respiration can be measured. In this experiment the intensity of light will be altered in each trail, and the rate of Photosynthesis will then be measured. As you rise from low light intensity to higher light intensity, the rate of photosynthesis will increase because there is more light available to drive the reactions of photosynthesis. However, once the light intensity gets high enough, the rate won’t increase anymore since there will be more-light than water and CO2; there will not be enough components from light, water, and CO2 to create the process of Photosynthesis. As CO2 dissolves and the amount of CO2 goes up, the pH will lower, which means the solutions color will change varying form red, orange and yellow, all pending on what the pH is at. CO2 will be produced from respiration, all while photosynthesis absorbs the CO2. This means that when the rate of photosynthesis is less than respiration, pH levels will decrease, and CO2 concentration will increase. Vis versa, when pH levels increase

The rate of photosynthesis can be determined different ways. Because oxygen is a product of photosynthesis and the Elodea plant is submerged in water, the oxygen is released in bubbles that rise to the surface of the water in the beaker. In this experiment, the rate of photosynthesis for each degree of light intensity can be measured by counting the number of bubbles released every 30 seconds for five minutes at each distance. The rate is the number of bubbles released per minute.

Photosynthesis is a vital process that requires to utilize energy for plants. This experiment was done to evaluate the effects of carbon availability on photosynthetic activity. The aquatic plant Elodea densa was placed into sodium bicarbonate solutions of five concentrations ranging from 0.1% to 1.0%, in five independent trials (excluding the negative control treatment of water). The temperature and light intensity was constant. The results indicated a directly proportional relationship between the availability of carbon dioxide and the rate of photosynthesis of Elodea Densa, as photosynthesis continued to increase with increasing amounts of bicarbonate. The most O2 amount of oxygen produced was with the 0.7% NaHCO3 concentration and least with the control of water. The null hypothesis that stated carbon concentration does not affect rate of photosynthesis of the aquatic plant was rejected. The predicted hypothesis that an increase in bicarbonate concentrations results in an increase in the photosynthetic rate was accepted. In conclusion, there is a significant increase in photosynthetic activity as the concentration of NaHCO3 increases.

In order to see the effects of pH and temperature on the enzymatic reaction of catechol oxidase when separated from potato tissue. We used a spectrophotometer to measure how much blue light energy is absorbed by benzoquinone. Benzoquinone is a product of catechol when it has been oxidized by different temperatures and pHs. We hypothesized that the benzoquinone absorbance rate would be faster when the pH added to the cuvettes were greater than the pH of the potato tissue. The pH of the potato tissue was pH 6. Our results show that pH 7 had the faster absorbance rate, slightly slower at pH 4, and slowest at pH

5.) Given that white light contains all colors of the spectrum, what growth results would you expect under white light?

13) If you ran the same experiment without passing light through a prism, what would you predict?

The purpose of this lab is to isolate photoheterotrophic bacteria using an enrichment culture from a sample of marine sediment. The enrichment culture provides the photoheterotrophic bacteria with specific conditions to promote growth.

Introduction: I am going to do an experiment that will test whether algae effects mud snails. I want to test this because I have learned about the effects of algae on certain ecosystems, and I want to know how it will affect the salt marsh. I am interested in how algae growth will effect mud snails. This project will help me learn the effects of algae on organisms living in the salt marsh.

The organism studied in these experiments was the Spinacia oleracea that was obtained from a local grocery store in Lincoln Nebraska. One experiment that was conducted was used to determine the rate of oxygen production of Spinacia oleracea in the dark. Another experiment conducted was used to determine the effect of light intensity on the net photosynthetic rate of a Spinacia oleracea. The effect of light wavelength on the net photosynthetic rate of a Spinacia oleracea was also conducted and observed. The last experiment conducted was conducted to identify the pigments in Spinacia oleracea in order to determine its chloroplast chromatography.

There should only be chads made from spinach leaves to allow for consistency in light receptor molecules. We could then use different food coloring in the petri dishes above the chads, with two beakers per color/ wavelength of light. If the beakers are filled with 20 chads each, this would allow a more exact representation of the rate of photosynthesis, based off of light absorption of the light receptors. Then, make measurements every minute for as long as it takes for all of the chads to float. As a result, I would predict that a graph of average chads floating/minute would look similar to the light absorption spectrum graph for chlorophyll

Cellular respiration is a procedure that most living life forms experience to make and get chemical energy in the form of adenosine triphosphate (ATP). The energy is synthesized in three separate phases of cellular respiration: glycolysis, citrus extract cycle, and the electron transport chain. Glycolysis and the citric acid cycle are both anaerobic pathways because they do not bother with oxygen to form energy. The electron transport chain however, is aerobic due to its use of oxidative phosphorylation. Oxidative phosphorylation is the procedure in which ATP particles are created with the help of oxygen atoms (Campbell, 2009, p. 93). During which, organic food molecules are oxidized to synthesize ATP used to drive the metabolic reactions necessary to maintain the organism’s physical integrity and to support all its activities (Campbell, 2009, pp. 102-103).

Six experiments were carried in this report concerning the effect that different environmental factors have on microbial growth. The results were recorded into tables where (+) symbolises growth and (–) symbolises no growth.