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10 questions
What happens during meiosis that does NOT happen during mitosis?
new cells are formed
DNA is passed on to the daughter cells
two rounds of cell division
Parent cells grow before both types of cell division.
In pea plants, purple flowers are dominant to white flowers. If one parent is heterozygous and the other parent is homozygous recessive, what percent of the offspring are expected to be purple?
0
50
75
100
Zach is conducting an experiment to observe which type of fertilizer will allow a plant to grow the tallest. He puts three plants in identical pots and places them in the same location. He waters the plants each day with the same amount of water. Then, Zach measures the plant growth and records his observations.
Which of these is the control group in Zach’s experiment?
the growth rate of each plant
the amount of water given to each plant
the type of fertilizer used in each plant
the pot that does not contain fertilizer
In Mrs. Garza’s science class, the students are reading about research done on a group of birds on the endangered species list. The researcher is an animal behaviorist who studies bird behaviors using video recordings to identify clues as to why the population is decreasing. Mrs. Garza asked the class if this researcher’s method could be considered an acceptable and reliable technique to discover scientific knowledge. She had students get into groups, vote on whether the research is acceptable or unacceptable, and provide reasons for the decision.
Which student group provides a reason that correctly supports its vote?
group 1
group 2
group 3
group 4
A scientist uses a computer model to investigate how heat flow in Earth's mantle results in the motion of tectonic plates. Which of these statements describes a benefit of using a computer model to simulate interactions in Earth's layers?
The model allows scientists to more reliably prevent the motion of tectonic plates.
The model allows scientists to more directly observe the motion of tectonic plates.
The model allows scientists to more carefully change the motion of tectonic plates..
The model allows scientists to more accurately predict the motion of tectonic plates.
A 9-kilometer-wide meteorite hit Earth 65 million years ago. Scientists have found a high concentration of iridium in the sedimentary clay layer from this time period. Iridium is very rare in Earth’s crust, but it is abundant in meteorites. Scientists believe this impact ended the Cretaceous Period and caused the dinosaur extinction. Which of these statements correctly describes whether this is a theory or a law and why?
It is a law because it includes a numerical analysis.
It is a law because it explains all causes of animal extinction.
It is a theory because it explains the cause of the dinosaur extinction.
It is a theory because it shows regular patterns from a generalization of the data
A construction company recently filled in a local pond to build new houses. During the following weeks, a local scientist noticed a decline in the mosquito population in the area. The scientist wants to conduct a study that will measure the change in the local mosquito population over a period of three months. Which research method would give the scientist the best data for conducting his study?
a survey asking residents about their observations of the local mosquito population
a collection device in the area that counts the number of mosquitoes caught weekly
a controlled lab experiment with mosquitoes that limits water access for the experimental group
a three-month case study observing the behavior of animals that depend on mosquitoes for food
Greek philosophers such as Democritus and Aristotle had ideas about the composition of matter. For example, Democritus believed matter was made of tiny, solid spheres that he called atomos, and Aristotle thought matter was made of earth, water, fire, and air. Aristotle's idea of matter was the accepted idea for over 2,000 years until John Dalton came up with a new theory about matter based on his experimental data. Which of the following best explains why Dalton’s theory became more widely-accepted over Aristotle's theory?
Dalton’s theory had repeated observations which were supported by extensive evidence.
Aristotle’s theory did not have enough direct evidence due to poor observational tools.
Dalton’s theory was more complete because more respected scientists found the ideas possible.
Aristotle’s theory became the law of conservation of mass when he documented phase changes of matter.
The formula for calculating density, D, is D=M/V
D=MV, where M represents mass and V represents volume.
For liquids, volume is often given in cubic centimeters (cc), which is the same as cm 3. If the density of an unknown liquid is 1.6 g/cc, what is the mass of 800 cc of the unknown liquid in grams (g)?
0.002 g
1.6 g
500 g
1280 g
If two stars had equal absolute brightness, what else would most likely be equal?
energy
distance from Earth
apparent magnitude
chemical composition
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