The movement in response to a stimulus is referred to as taxis. The lab was conducted in order to view the effects of light and water changes placed on environments of certain species. Positive phototaxis will occur if the isopodes exhibit a significant variation of attraction towards the dark side compared to the lighter side of the Petrie dish, and positive hydrotaxis will occur if the isopods migrate toward the wet side in comparison to the dry area. It was hypothesized that the A.vulgare would be attracted toward the dark side of the dish resulting in a negative phototaxis and postivite hydortaxis as the A.vulgare would attract more toward the wet environment then the
Kinesis Behavior Taxis behavior is the direct response of an organism towards a stimulus, while Kinesis is demonstrated in random movement in all directions though unresponsive means, though possibilities of indifference or contentment. For example, if when we were to introduce the fire to one side of the container and immediately all the crickets scuttled to the other side, that would be Taxis movement; As well as if we introduced the fire and the crickets did not change their movement patters in the slightest, that would be Kinesis. Controlled
Separating the halves and putting one in the light and the other in the dark was a condition for the experiment. The experiment could have been improved if we placed each half with soil and observed the new data. A good follow up experiment would be on animals or insects and how the interact with its environment. We could take it to another surrounding and record its reactions to its new habitat. The data would be recorded in a table.
As a whole, the class was asked to create and carry out at least three environmental differences that would help create and single out variables to help find the most desirable environment for the isopods. With background research, isopods are perceived as loving areas with moisture, preferably under rocks and soil, with decaying material for consumption. With this information, and collecting bugs, we were told of a few techniques and different variables to keep them alive until needed for the actual experiment. Our three trials with isolated variables were experimenting with different food sources, consisting of starch and sugar, whether they are attracted to a damp or dry environment, and one of which had a light and dark side. Our hypotheses were that the isopods would prefer the strawberries with the glucose in them, along with a damp environment and a longing for the dark.
Grab two dissecting pins and place them one on each end of the earthworm. After the earthworm is well placed in the tray, grab the scalpel and start opening the worm carefully, do not press too much because then the intestines will open too. Once it’s fully opened, we will use the dissecting pins and the dissecting probe. With the dissecting probe we keep on opening the body to fully see the earthworm from the inside. Grab the pin and place them one on each side, as much as you want to see the whole earthworm’s insides.
IBDP HL BIOLOGY - PRACTICAL 3 The colour of Beetroot is due to the presence of a red pigment, betacyanin in the cell sap. As long as the cells and their membranes are intact (that is not damaged), the betacyanin remains inside the vacuoles in the cells. However, if the membranes are stressed or damaged, betacyanin will leak through the membranes and produce a red colour in the water surrounding the beet tissue. The intensity of this red colour will allow for the assessment of the damage produced by experimental treatment 1) Aim To investigate the effect of temperature on cell membranes in beetroot (Beta vulgaris) 2) Research Question How does the temperature of the water bath (30 °C, 40°C, 50°C, 60°C, 70°C) affect the absorbance reading and the amount of the betacyanin that leaks out of the cell membrane when factors like duration of experiment, number of discs of beetroot used, surface area of each discs and volume of water are kept constant? 3) Hypothesis My hypothesis is that the greater the temperature, the more betacyanin will leak out of the cell through the cell membrane as the cell membranes will be under more stress and be more damaged, the higher temperature will also result in a faster rate of diffusion.
The hypothesized result was that the furthest distance would be the most effective, and absorbance would decrease as the light became closer. The results supported the hypothesis and showed that the three distances all yielded a relatively similar and that all the absorbances were in fact lower than the control group. The results also showed that as the light was moved further away from the chloroplasts the DPIP was reduced faster, producing a lower absorbance. Effect of Light Wavelength In this experiment different colors of light were tested in order to see which caused the photosynthetic process to be the most efficient. Discs made of spinach leaves were deoxygenated and placed in beakers with different wavelengths of light in order to measure which wavelength produced the most oxygen the fastest.
(biotic). The desert hedgehog is an omnivore because it will eat insects such as beetles and wasps along with small vertebrates like mice and birds. The hedgehogs will also eat eggs and some plant material. An interesting fact about the hedgehog is how it protects itself against predators. It will roll into a ball so that its stiff spines are protecting itself.
Its application in agriculture B. How it would affect bees 1. Relations between bees and neonicotinoid-- when bees may absorb neonicotinoids 2. Effects of sub-lethal doses of neonicotinoid exposure on bees: experiment IV. Conclusion : Restate the effect of Neonicotinoids and solutions so far A.
She elaborates on the issue of spraying chemicals and if it is increasing or decreasing the progress in the world. Carson’s article states that we are hurting ourselves more than we benefit ourselves from the spraying of harmful chemicals, and that we endanger our environment with these chemicals. In order to persuade the progressive intellectuals of this argument, Carson provides data to show the actual harm the pollution from the chemicals is causing, and provokes fear in her audience. In order to make her argument appear reasonable, Rachel Carson uses scientific observation to demonstrate how chemicals are the cause of killing pests. Carson provides rational examples to show the harm that pollution is causing to the earth and pests.