1. Test Taking Strategies: Keys to Success
STAAR BIOLOGY

2. Test Taking Tip: Read Question, Cover up Choices, Predict your Answer
Key 1: Circle the clue/key words
(1) Get a basic idea about the topic
(2) Recall basic definition or description
Key 2: Use the drawings
(1) Facts On the Figure (FOF)
(2) Draw it
Test Taking Tip: Working Backwards through the Answer Choices,
Key 1: Begin at answer (D) and work toward (A)
(1) You force yourself to examine answer choices more carefully
(2) Eliminate careless reading errors
Key 2: Eliminate Distractors (incorrect answers)
(1) Physically mark them out in your test booklet
Test Taking Tip: Answer The Question Asked (ATQA)
Key 1: Can be multiple questions in text of a problem
(1) Answer the last question asked

3. Which structure is indicated by the letter X? F Active Site
G Substrate
H Enzyme-Substrate Complex
J Competitive Inhibitor
Answer: F

4. C Cells use enzymes to manage cell metabolism
Which statement best describes the specificity of enzymes for the substrate in a chemical reaction?
A The suffix – ase is used to identify the specific enzyme-substrate pairing
B The bonding sites of enzymes to substrate fit like pieces in a jigsaw puzzle
C Cells use enzymes to manage cell metabolism
D Enzymes are created during protein synthesis
Answer: B

5. F Which enzymes work in solutions with a pH of 8?
A group of students is interested in learning how enzymes work in conditions of varying pH, and they discuss several questions to use as a focus for an investigation. Which is the most appropriate investigable question for an experiment about enzyme reaction rates and pH?
F Which enzymes work in solutions with a pH of 8?
G How does the pH of citric acid compare to the pH of hydrochloric acid?
H What is the optimal pH for catalase?
J What types of solutions have a pH of 6?
Answer: H

6. Examine the chemical equation above
Examine the chemical equation above. Which molecule stores the greatest potential energy?
A 6CO
B 6H2O
C C6H12O6
D 6O2
Answer: C

7. F There is more energy stored in the reactants than in the products.
Compare the reactants and products in the chemical equations above. Which statement best describes the relation between matter and energy?
F There is more energy stored in the reactants than in the products.
G Energy is transferred through metabolic processes.
H Carbon dioxide is the basis for carbohydrates.
J Breaking down glucose requires 36 molecules of ATP.
Answer: G

8. B Repeat the experiment to see if the results are the same.
Students perform an experiment to determine if plants carry out cellular respiration. They set up two test tubes using Elodea, a water plant. Each test tube contains water, 10 drops of bromthymol blue (BTB), and an Elodea sprig. Students seal the test tubes with stoppers and place Test Tube A in a test tube rack by a window and Test Tube B in a rack inside a cabinet. After two days, students discover the solution in Test Tube A is unchanged and the solution in Test Tube B has changed color. They wonder if plants only respire in dark conditions. Which lab setup would help them test their new hypothesis?
A Place different species of water plants under the same conditions as Test Tube B.
B Repeat the experiment to see if the results are the same.
C Set up Test Tubes C and D exactly like Test Tubes A and B. Place an aquatic snail in C and D. Place C by the window and place D in the cabinet.
D Repeat the experiment using a CO2 sensor to test for carbon dioxide in Test Tube A and Test Tube B.
Answer: D

9. Which two species are most closely related?
A Species 1 & 2
B Species 2 & 3
C Species 3 & 4
D Species 1 & 4
Answer: C

10. Which statement best represents the illustration?
F Wolves, bison, and horses are mammals.
G Wolf, bison, and horse structures show no evidence of relationships.
H Wolves, bison, and horses evolved in the same habitat.
J Wolves, bison, and horses share homologous structures
Answer: J

11. According to the diagram, which of the following pairs of insect groups likely share the most homologies?
A aphids and bees
B wasps and beetles
C bees and wasps
D moths and mosquitoes
Answer: C

12. G grasshoppers and mosquitoes H mosquitoes and flies
According to the diagram, which of the following pairs of insect groups likely share the least homologies?
F beetles and moths
G grasshoppers and mosquitoes
H mosquitoes and flies
J beetles and bees
Answer: G

13. The letter A in the food web most likely represents an organism that is –
A saprophytic
B heterotrophic
C autotrophic
D parasitic
Answer: C

14. Self-sustaining ecosystems must have the greatest biomass at trophic level –
J 4
Answer: F

15. According to the diagram, gases released during animal respiration contain carbon atoms that will most likely become part of –
F the ozone layer
G glucose molecules
H root respiration
J ocean uptake
Answer: G

16. Peptide bonds in proteins can be broken down by the enzyme peptidase
Peptide bonds in proteins can be broken down by the enzyme peptidase. Adrian orders a hamburger and French fries for lunch. He adds cheese and mayonnaise to his hamburger, and then sits down to eat lunch with his friends. Which structure would most likely results from the action of peptidase in Adrian’s small intestine?
A lipid
B glucose
C amino acid
D hydrocarbon
Answer: C

17. The overall roles of DNA and RNA are illustrated
The overall roles of DNA and RNA are illustrated. Which process is represented at Point 3?
F transcription
G replication
H translation
J mutation
Answer: C

18. A The offspring experienced a genetic mutation.
A plant that grows red flowers was crossed with the same kind of plant that grows white flowers. Their offspring grew pink flowers. Which best explains why the offspring grew pink flowers?
A The offspring experienced a genetic mutation.
B The offspring resulted from asexual reproduction
C The genes for flower color exhibited incomplete dominance
D A gene for pink-colored flowers was recessive in one of the parents
Answer: C

19. A student’s mother is heterozygous for attached earlobes, a recessive trait. The student’s father is also heterozygous for that trait. What is the percent likelihood that this student has attached earlobes?
A 0 %
B 25%
C 50%
D 75%
Answer: B

20. A The amount of cellular energy would decrease.
During an experiment on aerobic cellular respiration, a biologist limits the amount of phosphorous available to a cell culture. How might this affect the cell?
A The amount of cellular energy would decrease.
B The amount of cellular energy would increase.
C The amount of glucose produced would increase.
D The amount of glucose produced would decrease.
Answer: A

21. Catalase is an enzyme that speeds up the decomposition of hydrogen peroxide (H2O2) into water and oxygen. Students conducted two investigations to determine the ideal conditions for the function of catalase. One investigation compared catalase activity at different values of pH. The other investigation compared catalase activity at different temperatures.
Answer: H
According to the data in the graph, which pH and temperature combinations provides the best conditions for catalase to function?
F pH 5 and 4°C H pH 7 and 37°C
G pH 5 and 25°C J pH 7 and 50°C

22. A Eukaryotic organelles contain DNA similar to bacterial DNA.
The endosymbiotic theory of eukaryote evolution states that organelles in eukaryotic cells are derived from bacteria. Which statement is the strongest evidence in support of the endosymbiotic theory of eukaryote evolution?
A Eukaryotic organelles contain DNA similar to bacterial DNA.
B Eukaryotic organelles stop functioning outside of a plant cell.
C Eukaryotic organelles are similar in size and shape to bacteria.
D Eukaryotic organelles can reproduce through sexual reproduction.
Answer: A

23. What is the main function of the projections on the HIV?
F They protect the virus and give it its structure.
G They aid in respiration.
H The help the virus invade its host.
J The help the virus move and grow.
Answer: H

24. In order to digest milk, the human body must manufacture a protein called lactase. When the digestive system requires lactase, it manufactures the protein based on information stored in what molecule?
A DNA
B ATP
C CO2
D H2O
Answer: A

25. A an anaerobic environment outside the cell
Shira is analyzing samples of red blood cells using a microscope. Her observations are shown below.
Shira observes that the shape of Cell A appears normal, which Cell B appears swollen and Cell C is shrunken. The apparent shrinking of Cell C indicates the reaction of the cell to what?
A an anaerobic environment outside the cell
B lower solute concentration outside the cell than inside
C more oxygen inside the cell than what can be utilized
D higher solute concentration outside the cell than inside
Answer: D

26. G by reflecting sunlight H by deflecting desert sand
An ocotillo shrub is a desert plant that is characterized by small leaves and a wax coated stem. How do these structures most likely provide a survival benefit for this plant?
F by conserving water
G by reflecting sunlight
H by deflecting desert sand
J by protecting it from predators
Answer: F

27. J complex organic compounds
Plants make sugars in the presence of sunlight in a process called photosynthesis. What form of carbon do the plants take in for this process?
F glucose molecule
G carbon dioxide
H single carbon atoms
J complex organic compounds
Answer: B

28. Sheila ran around a track four times
Sheila ran around a track four times. She felt the need to breathe harder and faster. What were her muscles requiring?
A more carbon dioxide
B more nitrogen
C more oxygen
D more water
Answer: C

29. A A disease has affected only the dark winged peppered moth.
Peppered moths can have either a light wing color or a dark wing color. A scientist studied populations of both light and dark peppered moths over a 10year period. A graph of the data he collected is shown.
Based on the graph, which is the best conclusion to make about changes in the moth populations by the end of the study period?
A A disease has affected only the dark winged peppered moth.
B At present, wing color is not a factor in the success of peppered moths.
C A new food source has become available only to the light winged peppered moth.
D At present, dark winged peppered moths are being naturally selected for survival.
Answer: D

30. Which statement concerning the reproductive cells shown is correct?
A The cells are produced by mitosis and contain all the genetic information of the father.
B If one of these cells fertilizes an egg, the offspring will be identical to the father.
C Each of these cells contains only half the genetic information necessary for the formation of an offspring.
D An egg fertilized by one of these cells will develop into a female with the same characteristics as the mother.
Answer: C

31. F Heat allows the sugar molecules to bond more quickly.
Illustration 1 shows sugar that has formed a bond by the action of an enzyme. Illustration 2 shows the enzyme, and Illustration 3 shows the enzyme after the addition of heat.
How does the addition of heat affect the ability of an enzyme to help the sugar molecules form a bond?
F Heat allows the sugar molecules to bond more quickly.
G Heat provides places on the enzymes for other molecules to bond
H Heat changes the enzyme so that the sugar molecules can no longer bond.
J Heat changes the chemical composition of the sugar molecules so they no longer need the enzyme.
Answer: H

32. Segment 1 Segment 2 Segment 3 Segment 4
Four different segments of a DNA molecule are represented below.
Segment 1 Segment 2 Segment 3 Segment 4
T–A–G–G–C G–G–T–G–A G–A–T–T–A C–A–A–T–G
A–T–C–C–G C–C–A–C–T C–C–A–A–T G–T–T–A–C
There is an error in the DNA molecule in
F segment 1, only
G segment 3, only
H segments 2 and 3
J segments 2 and 4
Answer: G

33. A presence of pathogens in antibiotics
If the same antibiotic is used too many times, it can become less effective against a certain type of bacteria. This observation is best explained by the
A presence of pathogens in antibiotics
B production of antibiotics by white blood cells
C replication of viruses that attach bacteria
D survival and reproduction of unaffected bacteria
Answer: D

34. When changes occur in the genes of sex cells, these changes
A lead to mutations in the parent organism
B are always harmful to the offspring
C can be the basis for evolutionary change
D only affect asexually reproducing organisms
Answer: C

35. F environmental factors causing gene mutations in plants
On hot, dry days, guard cells often close stomata in plant leaves, conserving water. This is an example of
F environmental factors causing gene mutations in plants
G finite resources acting as selecting agents for evolution
H a feedback mechanism for maintaining homeostasis
J differentiation in plants as a result of stimuli
Answer: H

36. F both substances to enter the cell G substance B to enter the cell
The diagram above shows two molecules, A and B, entering a cell. Active transport is being utilized for?
F both substances to enter the cell
G substance B to enter the cell
H substance A to enter the cell
J neither cell is being moved via active transport
Answer: H

37. A live bacteria that ingest viruses
When a new viral infection appears in a population, scientists usually try to develop a vaccine against the virus. Which substances would most likely be contained in the new vaccine?
A live bacteria that ingest viruses
B white blood cells from an infected individual
C weakened viruses associated with the infection
D a variety of microbes that will attack the virus
Answer: C

38. H tissues and organelles J organelles and cells
Which levels of biological organization do stages 2 and 7 have in common?
F cells and organs
G cells and tissue
H tissues and organelles
J organelles and cells
Answer: J

39. The correct order for the stages of the cycle is A B, F, D, A, C, E
B A, B, C, D, E, F
C A, F, C, E, B, D
D C, B, A, D, E, F
Answer: C

40. If 15% of a DNA sample is made up of thymine, T, what percentage of the sample is made up of cytosine, C?
F 15%
G 35%
H 70%
J 85%
Answer: G

41. A Species B and C can be found in today’s environment.
Which statement concerning the evolution of species A, B, C, D, and E is supported by the diagram below?
A Species B and C can be found in today’s environment.
B Species A and D evolved from species E.
C Species A and C can still interbreed.
D Species A, B, and E all evolved from a common ancestor and all are successful today.
Answer: A

42. Which two processes are most closely associated with structure A?
The amoeba represented in the diagram below is a single-celled organism.
Which two processes are most closely associated with structure A?
F insertion and deletion
G nervous regulation and circulation
H active transport and diffusion
J replication and photosynthesis
Answer: H

43. F producers are not as important as consumers
One season, there was a shortage of producers in a food web. As a result, the number of deer and wolves decreased. The reason that both the deer and wolf populations declined is that
F producers are not as important as consumers
G more consumers than producers are needed to support the food web
H organisms in this food web are interdependent
J populations tend to stay constant in a food web
Answer: H

44. A Chloroplasts are visible inside the cells.
Scientists studying ocean organisms are discovering new and unusual species. Which observation could be used to determine that an ocean organism carries out autotrophic nutrition?
A Chloroplasts are visible inside the cells.
B Digestive organs are visible upon dissection.
C The organism lives close to the surface.
D The organism synthesizes enzymes to digest food.
Answer: A

45. An organelle that release energy for metabolic activity in a nerve cell is the
F chloroplast
G ribosomes
H mitochondrion
J vacuole
Answer: H

46. A wing shape is controlled by behavior
A student notices that fruit flies with the curly-wing trait develop straight wings if kept at a temperature of 16°C, but develop curly-wings if kept at 25°C. The best explanation for this observation is that
A wing shape is controlled by behavior
B wing shape is influenced by light intensity
C gene expression can be modified by interactions with the environment
D gene mutations for wing shape can occur at high temperatures
Answer: C

47. F twenty kind of amino acids in each protein
In all organisms, the coded instructions for specifying the characteristics of the organism are directly determined by the arrangement of the
F twenty kind of amino acids in each protein
G twenty-three pairs of genes on each chromosomes
H strands of simple sugars in certain carbohydrate molecules
J four types of molecular bases in the genes
Answer: J

48. The DNA of a human cell can be cut and rearranged by using A a scapel
B electrophoresis
C hormones
D enzymes
Answer: D

49. F can be used for photosynthesis
Much of the carbon dioxide produced by green plants is not excreted as a metabolic waste because it
F can be used for photosynthesis
G is too large to pass through cell membranes
H is needed for cellular respiration
J can be used for the synthesis of proteins
Answer: F

50. The females of certain species of turtles will sneak into a nest of alligator eggs to lay their own eggs and then leave, never to return. When the baby turtles hatch, they automatically hide from the mother alligator guarding the nest and go to the nearest body of water when it is safe to do so. Which statement best explains the behavior of these baby turtles?
A More of the turtles’ ancestors who acted in this way survived to reproduce, passing this behavioral trait to their offspring.
B The baby turtles are genetically identical, so they behave the same way.
C Turtles are not capable of evolving, so they repeat the same behaviors generation after generation.
D The baby turtles’ ancestors who learned to behave this way taught the behaviors to their offspring.
Answer: A

51. F decreasing competition G environmental carrying capacity
The size of a frog population in a pond remains fairly constant over a period of several years because of
F decreasing competition
G environmental carrying capacity
H excessive dissolved oxygen
J the depth of water
Answer: G

52. C biological catalysts D complex carbohydrates
Plants such as the Venus flytrap produce chemical compounds that break down insects into substances that are usable by the plant. The chemical compounds that break down the insects are most likely
A fats
B minerals
C biological catalysts
D complex carbohydrates
Answer: C

53. H Ecological succession will no longer occur in this marine ecosystem.
In December 2004, a tsunami (giant wave) destroyed many of the marine organisms along the coast of the Indian Ocean. What can be expected to happen to the ecosystem that was most severely hit by the tsunami?
F The ecosystem will change until a new stable community is established.
G Succession will continue in the ecosystem until one species of marine organism is established.
H Ecological succession will no longer occur in this marine ecosystem.
J The organism in the ecosystem will become extinct.
Answer: F

54. A increasing the diversity of life B recycling of nutrients
Many homeowners who used to collect, bag, and discard grass clippings are now using mulching lawnmowers, which cut up the clippings into very fine pieces and deposit them on the soil. The use of mulching lawnmowers contributes most directly to
A increasing the diversity of life
B recycling of nutrients
C the control of pathogens
D the production of new species
Answer: B

55. Which row in the chart below contains an event that is paired with an appropriate response in the human body?
Answer: Row 1

56. The diagram below represents a genetic procedure.
Which statement best describes the outcome of this procedure?
F Bacterial cells will destroy defective human genetic material.
G Bacterial cells may form a multicellular embryo.
H The inserted human DNA will change harmful bacteria to harmless ones.
J The inserted human DNA may direct the synthesis of human proteins.
Answer: J

57. This process is considered a mechanism of evolution because it
The diagram below represents the genetic contents of cells before and after a specific reproductive process.
This process is considered a mechanism of evolution because it
A decreases the chance for new combinations of inheritable traits in a species
B decreases the probability that genes can be passed on to other body cells
C increases the chance for variations in offspring
D increases the number of offspring an organism can produce
Answer: C

58. The diagram below represents a biochemical process.
Which molecule is represented by X?
A DNA
B starch
C protein
D ATP
Answer: D

59. G an antigen-antibody reaction H maintenance of homeostasis
The graph below shows the levels of glucose and insulin in the blood of a human over a period of time.
The graph represents
F an allergic reaction
G an antigen-antibody reaction
H maintenance of homeostasis
J autotrophic nutrition
Answer: H

60. The products would most likely contain A simple sugars B fats
C amino acids
D minerals
Answer: A

61. Strategies
Think about it
Apply knowledge
And
Recall