Experimental Design Basics
When heavy rains occur while apple or orchards are in bloom, the apple crop the following year is much smaller than normal. This information can best be described as a)an inference b)a hypothesis c)a prediction d)an observation
What is an observation?
A way to verify the result (improve the validity) of your experiments is ________.
*Answers may vary* What is repeating the experiment?
A decrease in pH of the water will decrease of the heights of the radish plants. This statement is known as the ______ in a experiment
What is the hypothesis?
1.Define the problem 2.Formulate a hypothesis 3.Perform the experiment 4.Analyze the experimental data
What are the steps of scientific method?
It is the variable that is being measured.
What is the dependent variable?
****An experiment was carried out to answer the question “Does the pH of water affect the growth of radish plants?” Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. Which sentence is a possible hypothesis that was tested in this experiment? (1) Does the pH of water affect the growth of radish plants? (2) Will the amount of water alter the heights of the radish plants? (3) The temperature of the water will affect the heights of the radish plants. (4) The pH of the water will affect the heights of the radish plants.
What is "The pH of the water will affect the heights of the radish plants"?
Tomato plants in a garden are not growing well. The gardener hypothesizes that the soil is too moist. To test this hypothesis accurately, the gardener could 1)plants seeds of a different kind of plant 2) Move the tomato plants to an area with less sunlight 3) change the pH of the soil 4) reduce the amount of water available to the plant
What is reduce the amount of water available to the plant?
****An experiment was carried out to answer the question “Does the pH of water affect the growth of radish plants?” Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. Which activity might help to increase the validity of this experiment? (1) repeating the experiment several times (2) using two different types of radish seeds in each group (3) using the same pH for both groups of plants (4) placing one set of plants in sunlight and one in darkness
What is repeating the experiment several times?
*****An experiment was carried out to answer the question “Does the pH of water affect the growth of radish plants?” Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. What was the dependent variable in this experiment? (1) heights of the plants (3) temperature of the water (2) pH of the water (4) type of soil
What is heights of the plants?
A student placed five geranium plants of equal size in five environmental chambers growing conditions were the same for each plant except that each chamber was illuminated by a different color of light of the same intensity. At the end of 20 days, plant growth was measured. Identify one constant factor.
What is -fertilizer -location of the plants (sunlight or shade) -temperature
Scientists have been experimenting with different forms of alternate energy to help reduce the amount of fossil fuels that are burned. They studied yeast, which convert plant materials into ethanol, a form of alcohol that can be used in automobiles. These experiments were carried out at room temperature. The scientists wondered whether more ethanol would be produced at different temperatures? - What is the independent variable and dependent in this experiment?
IV= Temperature
DV= production of ethanol
An explanation of natural events that is supported by strong evidence.
What is theory?
Define control group
What is a conclusion based on observation or evidence?
What is the difference between the control and experimental groups?
The control group is not given the independent variable while the experimental groups is given the independent variable.
A scientist is concerned about the effects of acid rain on newly fertilized fish eggs in lakes in the Adirondack Mountains of New York State. The scientist would like to investigate the hatching rates of these fish eggs in water at different acidic pH levels. The scientist designed an experiment that could show the effect of an acid pH on the hatching of these fish eggs. ______ is the dependent variable.
What is hatching of the fish eggs?
A_____ is a statement that can be tested and falsified (proven incorrect) using an experiment.
What is hypothesis?
An experiment was carried out to answer the question "Does the pH of water affect the growth of radish plant?" Two groups of ten radish plants were set up. One group was watered with water having a pH of 3.0, and the other group was watered with water having a pH of 7.0. Both groups of plants received the same amount and intensity of light, the same amount of water, and they were grown in the same type of soil. The heights of the radish plants were measured every 2 days for a period of 2 weeks. What is the experimental question? 1) Does the pH of water affect the growth of radish plants? 2) Will the amount of water alter the heights of the radish plants? 3) The temperature of the water will affect the heights of the radish plants 4) The pH of the water will affect the heights of the radish plants.
What is "Does the pH of the water will affect the heights of the radish plants"?