I LEAP PRACTICE QUESTIONS (answers are located at the end of the questions on the last two pages)

1. Which statement correctly describes a difference between plant cells and animal cells?

A. Animal cells have cell membranes, but plantcells do not.

B. Plant cells have cell membranes, but animalcells do not.

C. Animal cells have chloroplasts, but plant cellsdo not.

D. Plant cells have chloroplasts, but animal cellsdo not.

2. A student wants to perform an experiment to test how much water bean plants need for good growth. Which factor should be changed?

A The temperatureB The amount of lightC The amount of waterD The amount of soil

3. How much more rain fell in February than in November?A 4 centimetersB 6 centimetersC 14 centimetersD 16 centimeters

4.If the volume of the rock immersed in thegraduated cylinder is 60 mL, what will the level

of the water be after the rock is removed?A 30mLB 90mLC 120mLD 150mL

Look at this picture of a candle.

5. -Which statement is a direct visual observation?A. The candle is heavy.B. The flame is hot.C. The candle is lit.D. The wax is soft.

A Euglena contains a structure called a flagellum.What is the function of the flagellum?

A ReproductionB MovementC ProtectionD Food gathering

7. This is a diagram of a genetic cross. In guineapigs, black hair color is dominant (B) and whitehair color is recessive (b). What hair color are theguinea pigs’ offspring?

A. All blackB. All whiteC. Mostly black with some whiteD. Mostly white with some black

8. In a food chain, which are the most efficient users of solar energy?

A. HerbivoresB. CarnivoresC. OmnivoresD. Parasites

9. Green plants are important to animals because theplants________

A. consume food and give off oxygenB. consume food and give off carbon dioxideC. produce food and give off oxygenD. produce food and give off carbon dioxide

10. Snakes feed on mice. The mice eat grain crops.When the crops are plentiful, what will happen?

A. The mouse population will decrease.B. The snake population will increase.C. The snake population will decrease.D. The mouse population will not change.

11. If foxes and hawks are removed from this foodweb, one result will be —

A. a decrease in snakesB. an increase in rabbitsC. an increase in insectsD. a decrease in moles

12. After a recent experiment, a scientist noticed thatthe computer simulation varied from the actualexperiment. What should the scientist do?

A. Repeat the experiment several times in order toverify the results.

B. Adjust the computer’s program so it matchesthe actual results.

C. Ignore the actual results as inaccurate becausecomputers are very precise.

D. Ignore the simulation as inaccurate because ofa possible computer virus.

13. Why does a gamete produced during meiosis havehalf as many chromosomes as a daughter cellproduced during mitosis?

A. Meiosis does not involve a step in which theoriginal cell makes a copy of its chromosomes.

B. Meiosis involves a second cell division thatseparates identical chromosomes.

C. Mitosis does not involve a step in which theoriginal cell makes a copy of its chromosomes.

D. Mitosis involves a second cell division thatseparates identical chromosomes.

14. Which best describes the function of a ribosome?A. storing waste productsB. manufacturing proteinsC. digesting food particlesD. providing support

. A student draws and labels the parts of an animal cell, as shown below.

15. What organelle is labeled incorrectly?A. MitochondrionB. Golgi ApparatusC. VacuoleD. Ribosomes

16. The chart shows some levels of organization in anorganism.

CellTissueOrgan ? Organism

Which term best completes the chart?A. OrganelleB. Organ SystemC. MuscleD. Chemical

17. A student put a few drops of lemon juice into an uninflated balloon. The student tied a knot in the balloon, placed it in a shoebox and covered it with a lid.

The following day, the student opened the box and was able to smell lemon in the box. Through whatprocess were molecules able to pass through the balloon?

A. respirationB. fermentationC. diffusionD. radiation

18. Students were studying how temperature affectswater movement. The students added drops offood coloring to different temperatures of water.They measured the rates at which the food coloringspread throughout the water. Which tools wouldbest help the students complete their investigation?

A. beaker, thermometer, stopwatchB. meter stick, thermometer, beakerC. spring scale, thermometer, stopwatch

D. graduated cylinder, thermometer, balance

19. During photosynthesis, carbon dioxide (CO2) andwater (H2O) react in the presence of sunlight toproduce

A. oxygen (O2) and carbon ( C).B. glucose (C6H12O6) and carbon monoxide (CO.)C. glucose (C6H12O6) and oxygen (O2).D. hydrogen (H2) and oxygen (O2).

20. Which diagram best represents an exchange of gases between plants and animals?

A B

C D

21. The diagrams represent the way that three different organisms reproduce.

Which of these classifies the reproductive method of all the organisms shown above?A. segmentationB. buddingC. asexual reproductionD. sexual reproduction

22. The image shows a chromosome.

What is located on the chromosome?A. cellsB. genesC. enzymesD. organelles

23. In pea plants, tall plants (T) are dominant to short plants (t). The cross of two heterozygous tall plants is shown in the Punnett square below.

What ratio describes the most probable phenotypes resulting from this cross?A. 4 tall : 0 shortB. 3 tall : 1 shortC. 2 tall : 2 shortD. 1 tall : 3 short

24. Which pair of characteristics is common to allliving things?

A. having lungs to breathe and using wings tomoveB. having a vascular system and producing cellsduring growthC. having one or more cells and having the abilityto reproduceD. having a digestive system and responding tocertain environmental factors

25. The ability to respond to environmental stimuli isobserved inA. rocks.B. plants.C. rain drops.

D. sugar crystals.

26. Even on a windy day, most plants can remainupright. Which structure plays the greatest role inproviding a plant with this type of support?A. nucleusB. mitochondrionC. cell wallD. skeleton

27. Which statement correctly identifies a function of a chloroplast in eukaryotic cells?A. It contains cellulose, which helps a plant

conduct respiration.B. It contains cellulose, which helps an animal

conduct respiration.C. It contains a green pigment, which helps a

plant capture energy from sunlight.D It contains a green pigment, which helps an animal capture energy from sunlight.

28. What is the primary function of cell structure X?A. maintaining the cell’s shapeB. providing energy for the cellC. storing the cell’s food, water, and wastesD. monitoring what materials enter and exit the Cell

29. A scientist examines a structure within a cell thatcontains a large amount of genetic material. Whichstatement best identifies this structure’s function?A. It controls cellular activities.B. It stores food, water, and wastes.C. It gives the cell shape and support.D. It uses light energy to make sugars.

30. Which organelle provides evidence that this cellcan produce its own food from sunlight?

A. organelle 1B. organelle 2C. organelle 3D. organelle 4

31. Which statement describes how a plant cell’sfunctions would change in the absence of avacuole?A. The cell would not be able to produce proteins.B. The cell would lack energy to destroy foreign

objects.C. Fluid and wastes would not be stored within

the cell.D. Materials would not be transported between

the nucleus and cell membrane.

32. A scientist wanted to study a cell which lackedthe structure that contains the materials needed tocontrol cell activities. Which structure would needto be missing from the cell for this study to takeplace?A. nucleusB. vacuoleC. lysosomeD. mitochondrion

33. Sometimes when people eat, the food accidentallyenters a tube near the beginning of the respiratorysystem instead of the digestive system. This causesa person to cough. In which part of the respiratorysystem can food sometimes get stuck and causedifficulty in breathing?A. lungB. alveoli

C. tracheaD. diaphragm

34. A patient is having trouble reabsorbing excesswater from the digestive system. The first organthe doctor will most likely examine is theA. stomach.B. esophagus.C. small intestine.D. large intestine.

35. Redness and swelling may develop in an area neara wound. This reaction by the body means thatwhite blood cells are being carried to that area bywhich of the following?A. circulatory systemB. nervous systemC. muscular systemD. skeletal system

36. A walking stick is an insect that looks like a twigfrom a tree. Which characteristics are best used toclassify the walking stick as an animal, and not aplant?A. It is mobile, and it is a consumer.B. It is multicellular and eukaryotic.C. Its cells have nuclei and a cell membrane.D. It reproduces and makes energy using sex cells.

37. Which statement correctly describes a difference between plant cells and animal cells?A. Animal cells have cell membranes, but plant cells do not.B. Plant cells have cell membranes, but animal cells do not.C. Animal cells have chloroplasts, but plant cells do not.D. Plant cells have chloroplasts, but animal cells do not.

38. Which statement identifies a characteristic ofplants, but not animals?

A. They are producers.B. They need mitochondria.C. They conduct cellular respiration.D. They have internal vascular structures.

39. Which statement describes a major reproductive difference between plants and animals?

A. Plants are producers and animals are consumers.B. Most plants are dormant in winter; most animals are not.C. Plants have special cell structures that animals do not have.D. Most plants have both male and female structures; most animals do not.

40. Which statement correctly describes a difference between prairie dogs and strawberry plants?

A. Prairie dogs can reproduce sexually and asexually; strawberry plants can only reproduce sexually.B. Prairie dogs can reproduce sexually and asexually; strawberry plants can only reproduce asexually.C. Prairie dogs can only reproduce asexually; strawberry plants can reproduce both sexually and asexually.D. Prairie dogs can only reproduce sexually; strawberry plants can reproduce both sexually and asexually.

41. A gardener is investigating whether Brand Xfertilizer will increase the growth rate of the roseplants growing in an outdoor garden. Which roseplant would be the control for this investigation?

A. a rose plant in the garden given only water and sunlightB. a rose plant in the garden given Brand X fertilizer, water, and sunlightC. a rose plant in a container given Brand X fertilizer and placed inside a greenhouseD. a rose plant in a container given only water and sunlight and placed inside a greenhouse

42. Use the procedure below to answer the question.

Investigation Procedure1. Place ice cubes in a small metal dish.2. Pour some warm water into a jar.3. When the metal dish feels cold, place it on top of the jar.4. Watch the inside of the jar carefully to see if a cloud forms near the top of the jar.

Which drawing best represents the correct setup for the investigation?

A B C D.

43. A genetic mutation in a lizard population makes iteasier for the lizards to find food. Which statementbest describes what must also happen for naturalselection to occur?

A. The lizards must migrate to another area.B. The lizards must continue to have genetic mutations.C. The lizards must pass the mutated gene on to their offspring.D. The lizards must share their food with other lizard populations.

44. In some horses, black hair is a dominant genetic trait to white hair. The trait for black hair is represented as B, and the trait for white hair is represented as b. Which Punnett square shows a cross between two horses resulting in a 75% chance of the offspring having black hair and 25% chance of the offspring having white hair?

A B C. D

45. Scientists wanted to identify ways of studying dinosaur fossils without damaging them. Computerized scanners and X-ray machines were used to create detailed images. These images were used to produce three-dimensional computer models of the fossils. Which statement best describes the relationship between science and technology that helped scientists to study these dinosaur fossils?

A. Science relies on technology for all of its discoveries.B. Technology is a tool used to advance scientific knowledge.C. Science answers the questions that technology introduces to scientists.D. Technology is a process that informs scientists about the natural world.

46. Which of these best identifies biotic factors in a forest environment?

A. plants, animals, and their surroundings; including wildflowers, birds, rocks, and waterB. the features of the habitat and decaying material; including soil, air, dead trees, and bacteriaC. the things living plants and animals need; including air, water, soil, and nutrientsD. producers, consumers, and decomposers; including wildflowers, deer, songbirds, and mushrooms

47. Abiotic factors in an environment include all of theA. plants, animals, fungi, and bacteria living in a habitat.B. air, water, and food that living organisms use to stay alive.C. organisms, including those currently alive and those that were once living.D. rocks, water, sunlight, nutrients, climates, and other nonliving characteristics.

48. Which statement does not describe a possiblefunction of chromosomes?

A. They regulate the proteins in a cell.B. They provide a cell with energy.C. They determine the gender of an individual.D. They influence the traits of the entire organism

49. How does the number of chromosomes in egg andsperm cells at the end of meiosis compare with thatin body cells?

A. They have half the number of chromosomes.B. They have twice the number of chromosomes.C. They have the same number of chromosomes.D. They have one-fourth the number of chromosomes.

50. A relative of the giraffe called an okapi has44 chromosomes in its skin cells. How manychromosomes does a female okapi have in her eggcells?

A. 11 chromosomesB. 22 chromosomesC. 44 chromosomes

D. 88 chromosomes

51. A scientist determines that a specific plant’sreproductive cells have 20 chromosomes. Howmany chromosomes do its non-reproductive cellscontain?

A. 10 chromosomesB. 20 chromosomesC. 30 chromosomesD. 40 chromosomes

52. Which statement describes the beginning and endproducts of meiosis?

A. One diploid cell becomes two haploid cells.B. One haploid cell becomes two diploid cells.C. One diploid cell becomes four haploid cells.D. One haploid cell becomes four diploid cells.

53. A scientist studied the number of eggs a species of bird lays each year. He found that the most common number of eggs laid in a year is three. Which statistical measurement did the scientist find?

A. the mean number of eggs laid in a yearB. the median number of eggs laid in a yearC. the mode of the number of eggs laid in a yearD. the range of the number of eggs laid in a year

54. Joanne’s science teacher cautioned the class to be skeptical when learning about new scientific discoveries. Why is it important to be skeptical about new discoveries in science?

A. because many scientific discoveries are not based on facts B. because most scientific discoveries have no scientific valueC. because most scientists make errors when formulating scientific discoveriesD. because all scientific discoveries must be examined critically before they can be accepted

55. In which situation would osmosis most likely occur in cells?

A. across a permeable membrane that separates solutions of the same concentrationB. across a permeable membrane that separates solutions of different concentrationsC. across a nonpermeable membrane that separates solutions of the same concentrationD. across a nonpermeable membrane that separates solutions of different concentrations

56. Which statement best describes the process of respiration?

A. Oxygen and sugar are used in the process that provides energy to cells; water and carbon dioxide are its waste products.

B. Water and sugar are used to in the process that provides energy to cells; oxygen and carbon dioxide are its waste products.

C. Oxygen and carbon dioxide are used in the process that provides energy to cells; sugar and water are its waste products.

D. Carbon dioxide and sugar are used in the process that provides energy to cells; water and oxygen are its waste products.

57. What is a difference between mitosis and meiosis?

A. Mitosis occurs in all the cells in animals and plants, while meiosis occurs in only in bacteria.B. In mitosis, the products are identical to the parent cell, while in meiosis the products are different from the

parent cell.C. In mitosis, one cell divides into two cells, while in meiosis two cells combine to make one cell.D. Mitosis involves separating the chromosomes, while meiosis involves only the cytoplasm of the cell.

1a. Has external gills Go to 6.1b. Does not have external gills Go to 2.

2a. Has scales Go to 3.2b. Does not have scales Go to 4.

3a. Has a shell turtle3b. Does not have a shell Go to 5.

4a. Has a tail as an adult Go to 6.4b. Does not have a tail as an adult frog

5a. Has legs lizard5b Does not have legs snake

6a. Has coastal grooves along the side salamander6b. Does not have coastal grooves along

the sidenewt

58. Trish constructed a dichotomous key to help identify the reptiles and amphibians living in a certain area. Which phrase describes a lizard?

A. an animal with scaly skin and a shell but no external gillsB. an animal with scaly skin and legs but no shellC. an animal with legs and coastal grooves but no tailD. an animal with external gills and a tail but no coastal grooves

59. What do scientists mean when they refer to a population?

A. all the organisms in an ecosystem B. all the species that share similar anatomical features C. all the animals that acquire resources through similar methodsD. all the interbreeding members of a certain species in an ecosystem

60. Which relationship is mutualistic?

A. an insect that lives and feeds on the body of an alligator B. an ant that lives on a plant and defends the plant from other insects C. a bird that migrates to follow the movements of the butterflies that it eats D. a deer that eats one kind of plant, which allows another kind of plant to grow in its place61. Which example describes a behavioral adaptation?

A. A bird builds its nest in the ash near a volcano.B. A whale has the ability to hold its breath for 20 minutes.C. A fox’s hair is white in the winter and brown in the summer.D. A monkey has long arms that allow it to swing from one branch to another.

62. A forest is flooded when a natural dam breaks, leaving the forest floor under two meters of water. Which animal is most affected by the flooding?

A. a crowB. a rabbitC. a squirrelD. a butterfly

63. Which resource is most likely found in large amounts in forest ecosystems?

A. ironB. woodC. plasticD. petroleum

Rabbit Population

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64. The graph above shows the population of a rabbits in a field over a seven-year period. Based on the data, what is the approximate carrying capacity in the field for rabbits?

A . 200B. 400C. 500D. 600

65. What is the main reason humans need nitrogen to survive?

A. Nitrogen is used in respiration to generate energy.B. Nitrogen is used in making the proteins in the body.C. Nitrogen is used to help the body eliminate wastes.D. Nitrogen is used by nerve cells to conduct impulses.

66. Which statement best describes the roles of photosynthesis and respiration in the carbon cycle?

A. Respiration and photosynthesis both add carbon to the atmosphere.B. Respiration and photosynthesis both remove carbon from the atmosphere.C. Respiration adds carbon to the atmosphere, while photosynthesis removes carbon from the atmosphere.D. Photosynthesis adds carbon to the atmosphere, while respiration removes carbon from the atmosphere.

67. Scientists have observed an increase in global temperatures over the past 100 years. Which phenomena do scientists believe contributes to the increase in temperatures?

A. an increase in undersea volcanic activity B. a decrease in the distance between Earth and the Sun C. an increase in certain gases released during the use of fossil fuels D. a decrease in the amount of water on Earth due to overconsumption

68. Food that is being digested passes from the stomach to the small intestine. There, it mixes with digestive juices such as bile and pancreatic enzymes. Bile helps the body absorb fat while the pancreatic enzymes are capable of digesting carbohydrates, fats, and proteins. During digestion, these juices flow to the small intestine and combine with additional materials to further break down food. Afterwards, the molecules from the digested food are moved into the bloodstream.

Which diagram shows how these structures work together to help digest food?

A. B.

C. D.

A student made this model of the human respiratory system from a plastic soda bottle.

69. Which sentences best explain how the model can be used to show how different parts of the respiratory system work together?

A. Balloon 1 represents the lungs and balloon 2 represents the diaphragm. Pulling balloon 2 down shows how the diaphragm causes air to enter the lungs.

B. Balloon 1 represents an alveolus and balloon 2 represents a capillary. The bottle shows that the alveolus and capillary must be close together for gases to move between them.

C. The bottle represents the lungs and the straw represents the larynx. Squeezing and letting go of the bottle shows how the lungs push air into and out of themselves.

D. The bottle represents the ribs and the straw represents the windpipe. Squeezing the bottle shows how the ribs help push air out of the lungs.

70. The bison herd on Konza Prairie has begun to show a genetic defect. Some of the males have a condition known as "rabbit hock" in which the knee of the back leg is malformed slightly. We do not yet know the genes controlling this trait but for the sake of our question, we shall assume it is a sex-linked gene and that it is recessive. Now, suppose that the herd bull (the dominant one which does most of the breeding) who is normal (XN) mates with a cow that is a carrier for rabbit hock. What are his chances of producing a normal son?

a. 0%b. 25%c. 50%d. 100%

Answer Key

1. D2. C3. B4. C5. C6. B7. C8. A9. C10. B11. B12. A13. B14. B

15. C16. B17. C18. A19. C20. B21. C22. B23. B24. C25. B26. C27. C28. A29. A30. B31. C32. A33. C34. D35. A36. A37. D38. A39. D40. D41. A42. C43. C44. C45. B46. D47. D48. B49. A50. B51. D52. C53. C54. D55. B56. A57. B

58. B59. D60. B61. A62. B63. B64. C65. B66. C67. C68. D69. A70. C