Certify Teacher -Science
According to the velocity time graphs below, which line(s) shows a vehicle that is speeding up?
B and D
All of the following statements about the relationship between force and motion are true except —
As the mass of an object increases, the amount of force needed to move the object decreases.
Genetic information is contained in the DNA of an organism. How does DNA code for specific proteins that are unique in each individual?
DNA codes for RNA which codes for amino acids which hook together to make proteins.
The diagram illustrates the relationships between organisms in an ecosystem. In addition to sunlight, which factor would need to be added to make this a stable ecosystem? (Competency 004)
Decomposers
The diagram below relates to the question that follows.Sarah looked at some pond water with a microscope. She used the low-power objective lens to look at some green algae. The picture below shows what Sarah saw through the microscope. If Sarah switched the lens from low power to high power, what would she see in the field of view?
Fewer cells than with the low-power view, but in greater detail.
Beans and coal both have stored energy. Which of the following correctly identifies where the energy that is stored in beans and coal comes from?
From the Sun's light.
Students in Mr. Rodriguez's sixth-grade class are busy reviewing their folders containing graded assignments submitted during the first semester. They were asked to compare their knowledge/skills on assignments representing their first attempt at experimental design and then their most recent attempt. Which of the following most accurately describes the form of assessment Mr. Rodriguez was implementing during this process?
Portfolios
In the laboratory investigation where students are tasked with measuring the rate of change of a ball rolling down a ramp, students must collect data from a stop watch as the ball rolls down the ramp. The teacher sets the minimum of trials to measure at five. How does the use of repeated trials reduce the amount of error in the experiment?
Repeated trials allow students to collect more data and ensure that the data collected is accurate and precise. If the numbers are not similar, students know that there is an error in the procedure.
Which of the following is the primary advantage of designing and conducting laboratory experiments rather than relying on observations of the natural world? (Competency 004)
Since selected variables can be controlled more easily in the laboratory than in the natural world, cause-and-effect relationships can be detected more readily
The chemical formula for photosynthesis is shown below. Which of the following choices correctly describes this process?
Six molecules of water plus six molecules of carbon dioxide produce one molecule of sugar plus six molecules of oxygen
Refer to the diagram below to answer the question that follows. What do the arrows below in the algae, shrimp, fish, seal, and polar bear food chain indicate?
The flow of energy through the food chain from the algae to the polar bear.
Which of the following is a correct sequence in the life cycle of a butterfly?
The pupa develops from the caterpillar.
Is a hamburger an example of stored energy? Explain why or why not.
Yes. It stores chemical energy that can be converted to other forms of energy.
Mrs. Lara is teaching a lesson to her 4th-grade class about the motion of a pendulum. She tied a string to one end of her yellow highlighter, held the other end of the string fixed, pulled the highlighter back a small angle, and released it. The object went back and forth. She did this several times while asking the class about the differences in the pendulum before it was released and after it was set in motion. Her demonstration to the class is an example of -
conservation of energy
The table below shows the rate of water loss in three different plants. One reason each plant loses a different amount of water is that each has —
different guard cells adapted to maintain homeostasis.
Study the diagram below; then answer the question that follows. Which two numbers in the picture above of a flower show the male and female parts?
1 and 2
Each figure below shows a force measured in Newtons pushing on a block. If there are no other forces pushing on the block, in which case is the acceleration of the block greatest?
4 Newton's ————-> 1 kilogram
Dorothy and Brian are expecting a baby. They would like their baby to have a different eye color than theirs even though they both have brown eyes and know that this is a dominant trait. If both parents are hybrid for eye color, what is the probability that the baby's eyes would be brown?
75%
Ms. Simmons' sixth-grade students are conducting an investigation to determine if mealworms are more active during the morning or afternoon. Student groups are observing and recording the activity levels of the mealworms twice during the morning and twice during afternoon time periods. At the end of a two-week period of time, the students will form their conclusions. What type of scientific investigation is described in this scenario?
A Descriptive study
Mr. Salinas wants to assess his sixth-graders' knowledge of Newton's first law of motion which states that an object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force. Which of the following examples would best illustrate an object being subjected to an unbalanced force?
A ball rolling off of a table
Students in Mr. Neeve's fifth-grade classroom are preparing a presentation highlighting their garden projects. They want to share data which illustrates the growth of two sunflowers over a three month period of time. Which of the following is the most appropriate way for presenting the growth of plants over time?
A line graph
What is the difference between an element and a compound?
An element is composed of only one kind of atom and cannot be separated into simpler substances. Compounds are a combination of elements that are chemically bonded together.
Use the illustrations below to answer the question that follows. In an experiment on photosynthesis, students were instructed to cover a portion of a leaf of a de-starched potted plant with opaque paper as shown in the figure above. Leaf "A"; was covered with a red strip; leaf "B"; with green, leaf "C"; with blue and leaf "D"; with black as shown in the picture above. When the starch test was done on the leaves after 4 hours, the result showed no starch in —
Any of the covered portions.
Ms. Ivy is incorporating constructivism into her lesson on the phases of the moon. Students are to make observations and draw diagrams of the moon twice per week for a total of 6 weeks. In keeping with the ideas of constructivism, which of the following activities should Ms. Ivy use after her students have completed their moon logs?
Ask students questions to help them identify patterns/cycles from the first month of the observations to the second month. With careful questioning, students will begin to see a cycle in the appearance of the moon.
Ms. Corpora wants her sixth-grade students to understand the process used in scientific investigations. She wants them to realize that scientists continually form a hypothesis about ways to solve a problem, test the hypothesis, form a conclusion, and then revise the hypothesis and begin the process again until the problem is solved. Which of the following activities would most effectively help students understand this?
Ask students to make a paper airplane that can fly at least 30 meters in a straight line. After students test the airplanes several times, she will stop them and ask them to think about the steps they went through from one trial to the next.
During a science activity the teacher, Ms. Sanderson, asked her sixth-grade students to close their eyes and sit quietly for 2 minutes. She then asked them to run in place for 2 minutes and then identify the body systems that were affected by the exercise. Even though the list is incomplete, which of the following is the best answer to this question?
Circulatory, excretory, muscular, and respiratory
The picture below shows a way you could hook up a battery, three wires, a light bulb and any other component to the circuit. iHow could you use this apparatus to test an item to see if it is a conductor of electricity?
Connect the item to be tested to the circuit by placing it in the gap shown and attached to both clips. The bulb will light up if the item conducts electricity.
A student tried to connect an electrical circuit as shown below.The light bulb did not light up. What can the student do to make the light bulb light up?
Connect the steel nails with a short piece of wire.
Ms. Sullivan is teaching a lesson to her 2nd-grade students on the environment and focuses on the adaptation and habitat of frogs. She wants her students to learn about the life cycle of frogs, what they require in order to thrive, what they eat, and how they interact with other wildlife. Which activity would have the most instructional impact on the students?
Construct a terrarium with frogs.
Ms. Phillips is a beginning first-grade science teacher. She understands she will be responsible for developing lessons and activities based on grade-appropriate science curriculum. As she presents concepts and introduces her students to concepts embedded within a science lesson, she will want to focus on which of the following as a possible extension activity?
Constructing models
You want to cook an egg in boiling water at the top of a mountain that is much higher than where you normally live. What, if anything, would you change in your normal cooking procedures in order to cook the egg to the same hardness?
Cook it for a longer time
Elizabeth is treading water in a lake talking to her friends when she notices her feet feel cool while her arms and shoulders feel warm. From her science class, she knows that the sun's rays warm the surface of the water and cannot reach toward the bottom of the lake, but doesn't understand why the water doesn't mix and become the same temperature like bath water does. What is the reason for this?
Cool water is more dense than warm water and stays on the bottom.
Students in Mr. Sepolio's sixth-grade science class are working on environmental science research projects designed to compare the natural resource consumption of the United States to that of other industrialized nations in the world. Which of the following most accurately describes the objective of this project?
Create an awareness of the impact people in the United States have on the depletion of natural resources in the world.
DNA is found in the nucleus of all eukaryotic cells. Which of the following best describes the reason DNA is "copied" during cell reproduction and is passed along to new cells in the organism?
DNA contains genetic information or "instructions" from the parent cells.
Mr. Tompson's students are studying heredity. He has asked his fifth graders to organize the labels shown below into the correct order. In which order would the students place the labels if they are organizing the genetic information from the simplest to the most complex?
DNA, genes, chromosomes
The graphs below relate to the question that follows. Grace's class measured the temperature outside four times a day for four days in a row. Their results are shown above. Based on this data, choose two days that were most likely cloudy.
Day 2 and 3
During a long-distance run on a hot day, an athlete produces large quantities of sweat. As a result, the kidneys change the rate of urine production. Why is this change in the human body important?
Decreased urine production allows the body to conserve water.
Select a factor that contributes to hunger in a developing country, and a solution for it.
Degradation of land; agricultural biotechnology
Mrs. Wade is teaching a lesson to her 4th-grade class on the period of a pendulum. She wants her students to perform a laboratory investigation to determine the effects of certain variables by asking them the following question: Does the mass of the object or the length of the string affect the period of the pendulum? She then has her class sorted in small groups, in which they construct their own pendulum and set out to design an experiment to answer this question. In order to minimize any possible inconsistencies in the data, Mrs. Wade might suggest which of the following to her students?
Each group performs several measurements and takes the average.
Ms. Heitman presented the following problems to her students. At the end of the practice she asked them what they noticed about the numbers as they converted them from the larger unit to the smaller unit. What should the students have noticed in the process of working these problems?
Each time the larger unit (m, g) was converted to the smaller unit (cm, mg), the students multiplied and moved the decimal to the right.
Ms. Ely is preparing her classroom materials for the upcoming year. She notices one of the chemicals she planned to use is out of date and should be replaced. How should she dispose of the outdated chemicals? (Competency 001)
Follow the directions described in the Material Safety Data Sheets (MSDS)
A spider has built a large web just outside a window of a kindergarten classroom where the children are able to view it easily. As part of a science activity, the teacher asks the children to take turns observing the spider and drawing a picture of it. When the class gathers to discuss and compare their drawings, the children realize that some of them have drawn different numbers of legs on the spider. An animated discussion follows, with several children insisting they drew the correct number of legs. Which of the following would be the teacher's best response at this point?
Have the children look carefully at the spider again to determine whether they need to change the number of legs on their drawings.
How do rubrics and spending time reviewing expectations foster success in the classroom?
Having a no secrets class means that grades are not a secret. Reviewing expectations and sharing assignment requirements communicates evaluation criteria.
Middle school students are conducting investigations through surveys in their neighborhoods to determine if their neighbors are knowledgeable about the effects of lawn fertilizers on Galveston Bay. Which of the following inferences can likely be drawn from the results of this investigation?
Ignorance about the effects of everyday household chemicals on the environment influences the way they are used.
Read the text below; then answer the question that follows. Deformities, such as legs protruding from stomachs, no legs at all, eyes on backs, and suction cup fingers growing from sides, are turning up with alarming frequency in North American frogs. Clusters of deformed frogs have been found in California, Oregon, Colorado, Idaho, Mississippi, Montana, Ohio, Vermont, and Quebec.Scientists in Montreal have been studying frogs in more than 100 ponds in the St. Lawrence Valley for the past 4 years. Normally, less than 100% of frogs are deformed, but in ponds where pesticides are used on surrounding land, as many as 69% of the frogs were deformed. A molecular biologist from the University of California believes that the deformities may be linked to a new generation of chemicals that mimic growth hormones. The same kinds of deformities found in the ponds have been replicated in laboratory experiments. How could pesticides cause deformities in frogs?
It interferes with DNA replication and gene production.
Read the stimulus information below, then answer the question that follows.Sixth graders in Mr. Miller's science class have been learning about an instrument used to measure acceleration forces - the accelerometer. At the end of class, when the students had just finished experimenting with the accelerometers they built in class the teacher asks them, as a homework assignment, to go to the Internet to learn more and write a short paragraph listing one application of the accelerometer to their everyday lives. At the start of the next class, the students reported back the results of their research. Which of the following best describes the educational benefit of this kind of assignment?
It is important that students connect the science they are learning in school to the world around them.
Sarah and Keith are making candy for a holiday party and begin to argue about whether the melting sugar is a chemical or physical change. Keith says his teacher, Ms. Ortega, said physical changes are only a change in the state of matter, not a change in the chemicals that make up the material. Sarah argues that melting sugar is a change in the chemical makeup of the sugar because it doesn't look like sugar anymore. Who is right?
Keith is correct; melting sugar is a physical change because only the state of matter was changed. After melting, the sugar is still sugar but in a liquid state.
How is using a class competition and artful thinking a good method to foster inquiry in a science classroom?
Learning is social and when students work together to generate questions and then evaluate the questions, they use engaging methods to refine and sort questions.
Students in an elementary school class will be investigating whether various beverages and common household liquids are acids or bases. They will test liquids such as orange juice, milk, water, and ammonia. Which of the following tools would be appropriate for testing whether these liquids are acids or bases?
Litmus paper
Jessie enjoys hiking to the top of Rock Hill when he visits his grandparents' ranch. He studies rocks and adds the best ones to his collection. After many summers of exploring, he has decided that Rock Hill was completely under water at one time. Which statement below best supports his conclusion?
Many of his rocks contain imprints of shells.
Refer to the photo below to answer the question that follows. Considering that the yo-yo was just released, does it possess more potential energy or more kinetic energy in this position?
More potential energy
Isabel is very interested in gerbils and wants to use her pet gerbils in this year's science fair experiment. She questions her teacher about conducting an experiment to determine the effects of varying levels of hormones on secondary sexual characteristics in young gerbils. How should the teacher respond?
Most science fair projects involving the use of animals must be approved by a school district review board
The periodic table of elements is a list of all known substances that make up the universe. These substances, called elements, are the "building blocks" of all other substances. These elements are placed in specific places on the periodic table — Choose the appropriate answer(s) from the list below: I. according to their physical properties or the way they look.II. alphabetically.III. according to their chemical properties or the way they act.IV. according to the period in which they were discovered.
Number I and III
Sixth graders in Mrs. Anderson's science class just finished building a simple device to measure the Earth's air pressure. Next, the teacher asks the students to go to the Internet to learn more and write a paragraph listing one benefit of integrating such an instrument in smartphones. The students reported back the results of their research. Which of the following results correctly represents the interconnected understanding of the concept the students just learned?
One benefit is that elevation readings derived from this instrument inside the smartphone greatly improves navigation information for its GPS.
Students in Mr. Weber's class are learning about cell structures. What is the major difference they should see between plant cells and animal cells?
Plant cells have a cell wall that offers support and chloroplasts containing chlorophyll, and animal cells do not.
Water droplets, prisms, and lenses in the eye all bend light. When light is bent from prisms or water drops in the sky, the individual colors spread out and form a rainbow. When the lens bends light in the eye, it focuses the light on the retina. Which term correctly describes the above phenomena?
Refraction
Jennifer is digging in the sand at the beach during her summer break. She notices that the sand she is sitting on is very hot, but as she continues to dig down, the sand gets cooler. She asks her mom to explain this to her. Which of the following is the best explanation?
Sand is an insulator or a poor conductor of thermal energy
How does studying acid rain's impact on vegetation help scientists understand that a change in pH in a diabetic will harm them due to acidosis?
Science is made of unifying concepts with similarities that can be used to infer.
During the first week of school, Mr. Chang's sixth graders were instructed to do an internet search to find at least 3 people that made significant contributions to scientific discoveries. The contributors the students' chose must match their racial/ethnic identity and gender. What did Mr. Chang want his students to realize during the process of completing this assignment,?
Scientific discoveries are made by men and women from diverse racial and ethnic groups.
Later in the school year, after conducting many experiments, Ms. Nero's students were more knowledgeable about experimental design. She asked them to think about the experiment they designed earlier in the school year to test the effectiveness of shampoo with conditioner included and shampoo with a separate conditioner on the softness and shininess of hair. She wanted them to consider revisions they would make now that they were more knowledgeable. Small groups met to discuss possible revisions to improve the experimental design and other conclusions they could have formed from the collected data. By having the students consider revisions in the design and conclusions formed during the experiment conducted at the beginning of the school year, Ms. Nero was demonstrating an understanding of the importance of —
Self-assessment
Fifth graders in Ms. Timmons class are struggling with understanding the water cycle. A common misconception among the students is that clouds create raindrops. How does the law of the conservation of matter explain this process more accurately?
Since matter cannot be created, the water vapor in the air changes form from a gas state to a liquid state when it is cooled.
Two dogs pull on a flat-bottom sled with forces of equal magnitude in the directions indicated by the arrows below. The dot represents the sled. Which arrow best represents the direction of motion of the sled?
Sled Direction of motion
Right before Anna was about to run in a long race, she drank a large glass of orange juice to get energy. Which of the following describes how the energy in the orange juice actually made its way from the Sun?
Solar energy ⇒ Chemical energy in the tree ⇒ Chemical energy in the orange ⇒ Chemical energy in the orange juice
Students in Ms. Dozier's sixth-grade classroom are conducting an experiment to compare the amount of sugar that can be dissolved in hot tea and cold tea. Each group has added a teaspoon of sugar into each beaker of tea and stirred three times. Students continue to add sugar until a precipitate forms at the bottom of the beaker. What concept will students soon discover about matter in this experiment?
Solubility increases with increasing temperatures.
During a science activity, two students connect two paper cups with a long piece of string. When the students stretch the string tight, they are able to talk to one another by speaking into the cups. Which of the following accurately describes the energy transformations that occur when someone speaks into this device? (Competency 004)
Sound energy ————> mechanical energy ———————> sound energy
Movies often create misconceptions in science because they have details for entertainment that are not true. For example, when a space ship explodes, there is sound. Why isn't there sound in space?
Sound is caused by a disturbance that transfers the energy through matter until it reaches an ear drum that transfers the disturbance to a sound in the brain. Space does not have matter such as air or water to transmit the disturbance.
Applying the principles of balanced forces, determine which team will win the tug of war and by how much force.
Team A by 5 N
Use the information below to answer the question that follows. A box on a table is subjected to a push from the left. At the same time, it is subjected to a push with greater force directly opposite on the right. Which of the following statements describes what will happen to the box?
The box will move toward the left side of the table.
Garbage is a big problem. In many cities and towns, garbage is taken away to landfills, which are often called "dumps." Some landfills are very big and may cover hundreds of acres. But even these big landfills are getting full and may have to be closed. Recycling is a good idea for solving the garbage problem. Which of the following do you think is an advantage of recycling?
The cost of conserving natural resources
An adult toad lays 6,000 eggs at a time in a pond. Which of the following graphs shows the number of tadpoles and toads that will most likely result in the pond from these eggs? (Competency 001)
The graph with more eggs, less tadpoles, and lesser toads. Data in this graph implies that 6,000 eggs will produce roughly 2,00 tadpoles, and from that number a significantly smaller number of toads will result from surviving their development phase. This graph is consistent with challenges toads face in surviving their development as they make their way past a gauntlet of predators
Ms. Bess plans to peak her sixth-grade students' interest in genetics and heredity by introducing her unit with questions about twins. Which of the following statements is not true about twins?
The height of identical twins will be the same when they reach adulthood because they both contain the same genes for height.
Ms. Porter's fourth-graders are observing the moon twice per week for a period of two months. They will draw a diagram of the moon and record the date of the observation in their lunar logs. Which of the following most accurately describes the concept students will learn form this activity? (Competency 004)
The moon phases appear in a repeating cycle. This 29-day cycle can be observed during the two-month time period
Which of the following correctly describes the molecular structure of a gas?
The particles are arranged at random and are so far apart that there is no force of attraction between them.
Ms. Fulton is heating crayon shavings on a hot plate and then pressing them together between bricks and sheets of aluminum foil to illustrate the way sediments in the earth are heated and then pressed to form metamorphic rocks. Which of the following additions to the activity is extremely important for students in understanding the concept about metamorphic rock formations? (Competency 004)
The teacher should guide students in relating the hot plate and pressure from the bricks to what actually happens in the earth
In a science experiment, 10mL of solution A are added to a test tube containing 10mL of solution B. The test tube is immediately sealed with a rubber stopper. The two solutions are both clear and colorless. As the two solutions mix, the test tube becomes warm and the contents become cloudy. Finally, as the test tube is left undisturbed for several minutes, a white solid settles to the bottom of the test tube covered by a layer of clear, colorless liquid. Which of the following is a correct conclusion about this chemical system form the beginning to the end of the experiment? (Competency 004)
The total mass of the system remains unchanged
The diagram below relates to the question that follows. Tara put an ice cube in a jar, put the lid on the jar, then placed the jar on a scale. The jar and the ice cube weighed 3 units as shown in Diagram A above. Tara came back one hour later and the ice cube had melted. Which of the following best describes why the weight did or did not change?
The weight did not change and the arrow should point to 3 units because the melted ice is just in a different form.
All of the following statements concerning exothermic reactions are correct, except _____________.
The word exothermic "within-heating" describes a process or reaction that absorbs energy in the form of heat.
An activity designed to introduce the metric system to fourth graders begins by asking students to use metric measurement to measure the length of their foot, their height, and the length of the classroom. It then asks them to use a thermometer and record the temp of the classroom in degrees Celsius and to use a metric scale to weigh themselves in kilograms. Why is this activity a good way to introduce the metric system?
This activity uses everyday objects and allows students to relate the metric measurements to the standard measurements with which they are already familiar.
Ms. Chen is incorporating the 5E Model of science instruction (Engagement, Exploration, Explanation, Elaboration, Evaluation) in her sixth-grade science lessons. The Elaboration portion of the lesson requires the students to apply the concept learned in the Exploration to a new situation. Why is it necessary for students to apply the concept in a different but related context?
This requires students to generalize the concept to a new situation and deepens their understanding.
In science class the students had been learning about weather and hurricanes. Working in groups, they analyzed the image below and had to answer questions beginning on Blooms Taxonomy Level 1 and progressing to Bloom's Taxonomy Level 5. (See questions below the image). Q1: What is the picture on the right? Q2: What happened to the house? Q3: What type of pressure created the storm? Q4: How does the weather channel and local news stations help families prepare for hurricanes? Q5: How does increased ocean temperatures affect the hurricane seasons? Q6: What would happen if the family was still in the house when the storm hit?Why is this strategy of progression important in the development of students?
This strategy scaffolds and supports the learning process as students move from concrete to abstract thinking.
Students in Ms. Rivera's class are using colored clay to make a model of the basic structure of an atom. If the students are going to use a different color for each part of an atom, how many colors do they need?
Three: one each for the proton, neutron, and electron
Plants are called producers in a food chain because they produce their own energy. How do plants produce their own energy?
Through a process called photosynthesis, plants capture energy from the sun and form glucose.
Use the information in the chart below to answer the question that follows. The Nature Club is planning a field trip to Piney Park to collect plant specimens. According to the newspaper forecast, what day should they go on their field trip?
Thursday, because the ground would have more time to dry out.
Sixth-grade students in Ms. Sandifer's class are working on a question designed to measure their knowledge of the organization of cells in the human body. The statement below is posted on the board. Choose the series of words that will correctly complete the statement. Statement:A group of cells working together to carry out a particular job is called _____________. A group of these working together to carry out a particular job are called _________. A group of these working together to do a particular job are called a(n) _________. A group of these working together to do a particular job make up a(n) __________.
Tissue, organs, system, organism
What is the benefit of using journals, written reports, and projects over formal multiple choice assessments in terms of monitoring student understanding?
Using products offers a window into student thinking and opportunities to coach with feedback.
A student placed a piece of chalk in a jar of vinegar. The student observed the jar each day and saw that the chalk got smaller each day. The student was probably trying to learn how —
Weathering changes rocks
During the Environmental Science Unit, the 6th grade science students collected samples from the fields surrounding the school. Students gathered soil samples, various types of leaves, and plants from the perimeter as well as the center of the field. The teacher tasked the students with measuring and cataloging the samples in their science journals. Which list of tools are the best choice for measuring the mass of the samples and viewing them up close?
a dissecting microscope and a triple beam balance
If the forces acting upon an object are balanced, then the object —
could be moving with a constant velocity.
Which of the following is generally an advantage of sexual reproduction over asexual reproduction?
greater variation in the genetic makeup of a population
Mr. Gonzales explained the lab safety rules to his eighth-grade students at the beginning of the school year but wants to make sure all of the students are aware of the safety guidelines before he begins any experiments. Which of the following would be the best way to insure that all of the students are aware of the lab safety rules?
have each student read and sign a lab safety contract
Raymond is on his skateboard moving with a certain amount of motion energy. He stops pushing forward and begins to slow down. While he is slowing down most of the energy is transformed into thermal energy of the rubbing wheel parts of the skateboard. The rest of the energy -
is transferred to the surroundings.
A part of de-starched leaf of a potted plant was covered with black paper strips on both sides and the plant was kept in sunlight for 8 hours. The leaf was then tested with iodine after boiling it in alcohol. Only the uncovered part of the leaf turned blue black. The inference is that -
light is necessary for photosynthesis.
Use the illustration below to answer the question that follows. The resistors R1 and R2 are connected in —
parallel in circuit I and in series in circuit II.
When cleaning the cage of the turtle in the classroom, the teacher must ensure that students wash their hands when finished because of the risk for illness due to which of the following —
salmonella bacteria that live on the exterior of some reptiles.
Some living things use a system of reproduction that is sexual while other organisms use asexual reproduction. Which type of reproduction is the most advantageous?
sexual reproduction because it provides a greater variety of organisms within the population
Mr. Horn is teaching his fourth-grade students about the process in which ions are formed. He asks students to role play the part of protons, neutrons, and electrons that make up 2 different atoms. He then explains the process by which electrons are lost to the other "atom" while the actors role play for the rest of the class. The strategy described in this passage is effective in aiding students' understanding of this process primarily because —
the role play allows students at this age to visualize a very abstract concept.
Students were given 2 trials at a time and required to draw conclusions. The first conclusion from the data differed from the final conclusion once all of the data was revealed. What was the purpose of this activity?
to demonstrate that repeated trials increase the reliability of data