Question

1. scientific investigations begin with
2. a logical interpretation based on what scientists already know is called an
3. a hypothesis is a tentative
4. in a controlled experiment, all
5. the variable that is deliberately changed is called the:

the one that changes in response is the:

1. a control group is exposed to the same
2. type of data that involves counting or measuring:

type of data that describes characteristics that cant be measured:

1. why do scientists try to use large sample sizes?
2. data analysis can support or
3. when are hypotheses tested by field observations?
4. a
5. what theory is the central organizing principle of biology?
6. plan an investigation to test the effect of water temperature on goldfish respiration. sketch your design below and identify the independent and dependent variables.

Explanation:

1. Scientific investigations start with an observation.
2. An inference is a logical interpretation based on prior - knowledge.
3. A hypothesis is a tentative explanation that can be tested.
4. In a controlled experiment, all variables are kept constant except the one being tested.
5. The variable that is deliberately changed is the independent variable, and the one that changes in response is the dependent variable.
6. A control group is exposed to the same conditions except for the variable being tested.
7. Quantitative data involves counting or measuring, and qualitative data describes non - measurable characteristics.
8. Scientists use large sample sizes to increase the reliability and accuracy of results and reduce the impact of chance.
9. Data analysis can support or reject the hypothesis being tested.
10. Hypotheses are tested by field observations when laboratory experiments are not feasible or when studying natural phenomena in their natural settings.
11. A scientific theory describes a well - tested explanation for a range of phenomena.
12. The central organizing principle of biology is the theory of evolution.
13. For the investigation on the effect of water temperature on goldfish respiration:

• Independent variable: Water temperature.
• Dependent variable: Goldfish respiration rate.
• Design: Set up multiple aquariums with goldfish. Use a water heater to set different water temperatures in each aquarium (e.g., 15°C, 20°C, 25°C). Count the number of gill movements (as an indicator of respiration) of the goldfish in each aquarium over a fixed time period (e.g., 5 minutes) for each temperature. Keep other factors like water quality, amount of light, and number of goldfish per aquarium constant.

Answer:

1. Observation
2. Inference
3. Explanation
4. Variables
5. Independent; Dependent
6. Conditions
7. Quantitative data; Qualitative data
8. To increase reliability and accuracy and reduce the impact of chance
9. Reject
10. When laboratory experiments are not feasible or when studying natural phenomena in their natural settings
11. Scientific theory
12. Theory of evolution
13. Independent variable: Water temperature; Dependent variable: Goldfish respiration rate. Design: Set up multiple aquariums with goldfish, adjust water temperatures using a water heater, count gill movements over a fixed time period while keeping other factors constant.