7th Grade EOC Part I

Which knob is paired correctly with its objective lens?

• Low power objective: fine focus; high power objective: coarse adjustment
• Low power objective: coarse adjustment; high power objective: fine focus
• It doesn’t matter which knob you use with either objectives.
• Are one celled

Which one of the following questions can best be answered scientifically?

• Do plants grow taller in the summer?
• Does salt have a smell?
• What color will strontium burn?
• Does the amount of fertilizer affect plant growth?

A scientist is studying the effects of temperature on wakefulness in white mice. She will measure the number of minutes per hour the mice are awake. 1.  Which groups should the scientist use to conduct her experiment?

• Groups 1 & 2
• Groups 2 & 3
• Groups 1 & 3
• All Three Groups

A student wants to find out which brand of fertilizer will make plants grow fastest. She collects 4 different brands of fertilizer and 4 different plants. She places brand 1 on a pepper plant. Brand 2 on a broccoli plant. Brand 3 on a corn plant and brand 4 on a strawberry plant. After running the experiment she sees that brand 3 caused the corn plant to grow most and concludes that brand 3 is the best fertilizer to use to make plants grow the fastest. What is wrong with the design of this experiment?

• She was testing more than one variable at a time.
• She used fruit and vegetable plants; she should have only used vegetable plants.
• All brands of fertilizers are exactly alike.
• Plants do not grow at the same rate.

Consider this hypothesis: “The amount of salt in water will increase the rate at which water will leave the cells of a potato placed in the solution.”  What is the independent variable in this experiment?

• Temperature of water
• Percent of salt in water
• Surface area of potato
• Rate that water leaves the cells of the potato

1.  Based on the chart below, chose the best graph that represents this data. All potatoes started with having a mass of 10 grams.

• A
• B
• C

Lisa, a life science student, wants to know, “What effect temperature will have on the number of corn seeds that germinate in a 48 hour period?” After doing several trials, she graphs the data that she has collected to try and answer her question. Below is the graph of her data.

• As the temperature decreases, the number of corn seeds that germinate increases.
• As the number of corn seeds that germinate increases, the temperature decreases,
• As the temperature increases, the number of corn seeds that germinate increases.
• As the number of corn seeds that germinate decreases, the temperature increases

A student wants to find out which brand of fire ant killer will kill the most fire ants. She buys four different brands of fire ant killer and collects ten different colonies of fire ants from her yard. She places 150 ants from each colony into an individual container and places 3 grams of ant killer into each container. After running the experiment, she notices that Brand 3 kills the most fire ants for each colony that she collected. The data table summarizes the design and the results of her experiment. What's the IV?

• The number of fire ant colonies
• The number of ants killed
• Number of fire ants
• The brand of fire ant killer

What is the dependent variable?

• The number of fire ant colonies
• The number of ants killed
• Number of fire ants
• The brand of fire ant killer

What part of the microscope allows more or less light pass through the slide?

• eyepiece
• stage
• low power objective lens
• iris diaphragm