Name: __ANSWER KEY_________________
Block: ______
Test Review Sheet:
Scientific Investigation/Characteristics and Basic Needs
(For questions 1-9 use the following problem)
You want to determine which kind of light plants grow best under, natural sunlight, fluorescent light, or
blacklight. You think that the plant under normal sunlight will grow the most. You measure the starting
heights of three house plants and then place each one under a different kind of light for 24 hours a day for
two weeks. You use the same kind of houseplants in the same kinds of pots, with the same amount of water
and the same kind of soil. At the end of the two weeks, you measure to see how much the plants grew. You
find that the plant under normal sunlight grew 4 cm, the plant under fluorescent light grew 2 cm, and the
plant under blacklight did not grow at all.
Identify the following from the experiment described above:
1. Problem:
What is the effect of the type of light on plant growth?
2. Hypothesis:
If a house plant is exposed to normal sunlight, it will grow taller than plants exposed to fluorescent
lights and blacklight.
3. Independent Variable:
Type of light
4. Dependent Variable:
Height of plant
5. At least 2 constants:
type of plant, pots used, amount of water, type of soil, time of experiment
6. Observation/Data:
Type of Light
Sunlight
Fluorescent
Blacklight
Height (cm)
4cm
2cm
0cm
7. Conclusion:
The hypothesis was proven since the house plant exposed to the sunlight grew the tallest (4cm)
compared to the fluorescent light (2 cm) and blacklight (0cm). One source of error is the lack of control
for light intensity. If one plant was exposed to a type of light which was more intense than the other
two lights, this may affect plant growth. In the future, you can further your research by testing the
effect of light intensity on plant growth.
8. Possible sources of experimental error:
It is possible for there to have been measurement error if you did not measure plant height
consistently each time (e.g. from the base of the stem to the top tip).
9. What is the control group in this experiment?
There is no control group because the plants are being compared to each other.
10. Why are control groups important to have when possible?
Control groups allow scientists to compare their experiment with what would happen under normal
conditions so that they can see if the independent variable had a significant effect on the experimental
group.
11. Explain the difference between qualitative and quantitative data:
Qualitative data describes observations taken with the five senses. These descriptions are usually
written in words.
Quantitative data describes numerical observations.
12. Why is it important to communicate the results of an experiment?
This allows scientists to share important findings with the community. This prevents the same
experiment from being done twice. This can also have a potential effect on laws and how humans live
everyday lives.
13. T or F, you always need to use ALL parts of the scientific method.
False.
14. T or F, the parts of the scientific method are always completed in order.
False.
15. Scientists often make tables and graphs to interpret data. Why do we analyze data?
We analyze data to learn from our experiment and to clearly present our findings to the public.
16. Why should you refer back to your hypothesis when writing a conclusion?
This keeps the experimenter focused on the original problem being investigated and allows them to
see whether their results supported their original hypothesis.
17. ____Uni-cellular___________ organisms are made up of one cell, and ____Multi-cellular___________
are made up of more than one cell.
18. If you are given an unknown specimen and you want to know if it is alive, what characteristics would
you look for? Include all of the characteristics of life.
Organisms that are alive need energy, can reproduce, are made of cells, have DNA, respond to stimuli
and can grow and develop.
19. Why are some organisms bigger than others? (think in terms of cells)
Organisms that are bigger than others have more cells.
20. How do living things get bigger if we all start out as one single cell?
Cells can grow, divide and multiply into more cells.
21. Mrs. Renaghan walked her dog outside yesterday morning, and as soon as she stepped outside she
started to shiver? Explain what the stimulus and response is in this situation and explain what it has to
do with homeostasis:
Stimulus: cold
Response: shivering
Homeostasis is when the body tries to maintain balance and healthy conditions. As humans our normal
healthy body temperature is 37 degrees Celsius (98.5 degrees Fahrenheit), as a result the cold
temperature alerted Mrs. Renaghan’s brain to tell her that the body was experiencing irregular
conditions. This stimulus caused the response of shivering which generates warmth.
22. ____Heredity_______ is the passing down of traits from parents to offspring.
23. Your hereditary information is found in your __DNA_______. It is known as the blueprint of your cells.
24. Define the word abiotic and give an example of something that is abiotic.
Abiotic –nonliving e.g. water, sunlight, soil
25. Define the word biotic and give an example of something that is biotic.
Biotic –living e.g. plants, animals
26. Explain the difference between sexual and asexual reproduction:
Sexual reproduction –when two parents make an offspring
Asexual reproduction –when one organism itself can produce offspring with the same DNA
27. Why do living things need to get and use energy?
All living things need energy for metabolism. Living organisms use energy to do daily activities e.g. eat,
move etc.