Biology

2012 Practice Test

1  A biology student wears protective gloves as he studies a bacterium cell under a microscope. Using the microscope, what observation does the student make that allows him to correctly classify the bacterium cell?

A The student observes that the bacterium cell is a single-celled organism, and therefore, the bacterium is a eukaryote.

B The student observes that the bacterium cell does not have a cell membrane, and therefore, the bacterium is a prokaryote.

C The student observes that the bacterium cell cannot reproduce, and therefore, the bacterium is a eukaryote.

D The student observes that the bacterium cell does not contain a nucleus, and therefore, the bacterium is a prokaryote.

2  Felicity draws and labels a model of a mitochondrion organelle in an animal cell seen under the microscope.

Which of the following is a function of mitochondria?

A Mitochondria convert fats to carbohydrates.

B Mitochondria process and package proteins.

C Mitochondria convert the energy of food into ATP.

D Mitochondria make their own food.

3  Amoebas are single-celled organisms that acquire food by surrounding food particles with their cytoplasm. This process is called –

A phagocytosis

B diffusion

C metabolism

D respiration

4  Wendell Stanley was an American biochemist who studied crystals of the tobacco mosaic virus. By studying the crystals, he inferred that viruses are not living organisms. More recently, some scientists have questioned whether viruses act as living organisms because they can manage to form replicates of themselves. By which process does a virus reproduce?

A A virus reproduces by producing four genetically unique haploid cells through meiosis.

B A virus reproduces by producing two genetically identical diploid cells through mitosis.

C A virus reproduces by incorporating its DNA or RNA into a host cell and using the host cell to make copies of the virus.

D A virus reproduces by forming spores that disperse when the virus explodes.

5  People with HIV have an increased risk of dying from secondary infections. Which of these best explains how HIV increases the danger of secondary infections?

A HIV produces antigens that damage red blood cells.

B HIV adds genetic material from harmful microbes.

C HIV destroys Helper T cells.

D HIV consumes beneficial microbes in the body.

6  Cell growth and the rate of cell division in multicellular organisms vary between different types of cells. Organism growth and repair occur as cells progress through the different phases of the cell cycle. Why is the cell cycle important to the growth of organisms?

A The cell cycle allows for all genetic information to be copied before cell division occurs so that each daughter cell has everything it needs to survive.

B The cell cycle allows for new genetic information to be processed so that the daughter cells can be altered to meet new needs of the organism.

C The cell cycle allows cells to grow to larger sizes to accommodate the increase in size of the organism as the organism grows.

D The cell cycle allows for the organism to make its own food when food sources are scarce.

7  Heather reads an article that describes how frogs within a specific species can change their gender. She reads that when the population of female frogs is high, some of the female frogs change their gender to become male frogs to maximize breeding opportunities. What should Heather conclude as the most likely mechanism through which the gender change occurs?

A cell differentiation as a result of an environmental factor

B cell differentiation as a result of a viral infection

C natural selection as a result of an environmental factor

D natural selection as a result of a viral infection

8  Scientists have discovered that certain cells with a defect in a gene called p53 can cause a serious disease. Gene p53 normally prevents the cell cycle from continuing until proper chromosome replication has occurred. Defective p53 genes can cause cells to undergo uncontrolled growth. Which type of disease is most likely to be caused by a defect in p53?

A cancer

B chicken pox

C strep throat

D pneumonia

9  Organic compounds found in living organisms are called biomolecules. Study the incomplete table comparing the structures of the four groups of biomolecules found in living organisms.

Biomolecule / Subunit in Biomolecule
carbohydrates
lipids
proteins
nucleic acids

Which table correctly matches the biomolecules with their subunits?

Biomolecule / Subunit in Biomolecule
carbohydrates / amino acids
lipids / glucose
proteins / glycerol and fatty acids
nucleic acids / nucleotides
Biomolecule / Subunit in Biomolecule
carbohydrates / glucose
lipids / amino acids
proteins / glycerol and fatty acids
nucleic acids / nucleotides

A C

Biomolecule / Subunit in Biomolecule
carbohydrates / glucose
lipids / glycerol and fatty acids
proteins / amino acids
nucleic acids / nucleotides

B D

Biomolecule / Subunit in Biomolecule
carbohydrates / glycerol and fatty acids
lipids / glucose
proteins / amino acids
nucleic acids / nucleotides

10  All organic molecules found in living organisms contain carbon. In addition to carbon, biomolecules contain atoms of other elements. Which element is found in nucleic acids that is not found in amino acids?

A oxygen

B nitrogen

C phosphorus

D hydrogen

11  The study of DNA began long before Francis Crick and James Watson developed the double-helix model of the DNA structure. The basic structure of the nucleotides, which make up a DNA molecule, was discovered in 1919 by Phoebus Levene. Levene discovered that nucleotides consisted of three parts. What are the three parts of every nucleotide?

A a nitrogenous base, a 5-carbon sugar, and a phosphate group

B a glycerol molecule and one to three fatty acids

C an amino group, a carboxyl group, and a side chain called an R-group

D carbon, hydrogen, and oxygen atoms

12  There are four types of nitrogenous bases found in DNA. Which of the following is not a nitrogenous base.

A Guanine

B Cytosine

C Leucine

D Adenine

13.

Some organisms, such as a chimpanzee and a human, have many similarities. Others, such as a zebra and a worm, have fewer similarities. What do scientists think is TRUE about the ancestors of these organisms?

A.  Chimpanzees and humans share a common ancestor with each other, but zebras and worms do not share a common ancestor with each other.

B.  Chimpanzees and humans share a common ancestor with each other, and zebras and worms share a common ancestor with each other, but chimpanzees and humans do not share a common ancestor with zebras and worms.

C.  Because chimpanzees, humans, zebras, and worms are separate species, none of them shares a common ancestor with any other.

D.  Chimpanzees, humans, zebras, and worms all share an ancient common ancestor.

14  RNA translation is represented in the diagram.

What is the purpose of translation?

A Each strand of DNA is paired with a complimentary strand to create a new DNA molecule.

B Hydrogen bonds between complementary strands of DNA are broken, creating two separate molecules.

C Part of a DNA sequence is copied into a complimentary RNA sequence.

D An mRNA message is decoded into a polypeptide.

15  Groups of genes that work together in prokaryotes are called operons. What role does an operon have in a prokaryotic cell?

A An operon halts DNA replication.

B An operon regulates gene expression.

C An operon destroys foreign DNA.

D AN operon creates new DNA.

16  Look at the drawing of a normal strand of mRNA and a mutation that takes place in the strand of mRNA.

What type of mutation has occurred?

A A substitution of the cysteine polypeptide with the stop polypeptide has caused the mRNA strand to delete the code for alanine.

B An insertion of an adenine base has caused changes in every amino acid on the mRNA strand following the point of insertion.

C An insertion of an adenine base has caused the mRNA strand to code for a stop codon.

D A substitution of the uracil base with an adenine base has caused the codon for cysteine to be changed to a stop codon.

17.

According to the theory of evolution by natural selection, which of the following is true?
A. / genetic traits that aid evolution are not passed on to offspring
B. / variation does not exist between members of the same species
C. / populations will change over time to better fit their environment
D. / no more offspring are born into a population than can survive

18  The Punnett square shows a cross between a homozygous red flowering plant and a homozygous white flowering plant.

Because neither the allele for the color red nor the allele for the color white is dominant, the flower color of the F1 generation produced by this cross is predicted to be –

A red.

B white.

C pink.

D red and white striped.

19  A Punnett square shows the predicted outcome of a dihybrid cross. In what ratio do the different traits in the dihybrid offspring almost always appear?

A 1:3:6:9

B 9:6:6:1

C 9:6:3:1

D 9:3:3:1

20  Diploid human cells have 46 chromosomes. How many chromosomes are in each human daughter cell produced by Meiosis 1?

A 13

B 23

C 46

D 47

21  Advances in DNA technologies have allowed scientists to sequence small genomes such as that of viruses and bacteria. In 1990, scientists from the United States and from other countries began the Human Genome Project. The goal of the Human Genome Project is to –

A create a new organism using human genetic material.

B find cures for the most common genetic illnesses in humans.

C develop a world-wide fund to pay for genetic research in humans.

D analyze the human DNA sequence.

22 A man treated his home with a pesticide that kills roaches. The first application of the pesticide killed 92% of the roaches. Two months later, he applied the pesticide to his home again, but the application killed only 65% of the roaches. What would best explain the decrease in the effectiveness of the pesticide?

A.  The pesticide is only effective against mature roaches.

B.  Once roaches learned how to fight the pesticide, they taught others.

C.  The surviving roaches were naturally resistant to the pesticide, and that resistance was inherited by their offspring.

D.  The pesticide caused some of the roach’s digestive systems to mutate and metabolize the pesticide.

23.

Which process results in greater genetic diversity in offspring?

A / genetic linkage
B / recombination of DNA during meiosis
C / crossing-over during mitosis
D / rearrangement of chromosomes in germ cells

24.

The diagram above shows a model of species divergence among some primates. If this model is correct, the greatest genetic differences would be found in the DNA sequences of which two species?

A. Tarsius bancanus and Cebus albifrons

B. Macaca sylvanus and Macaca mulatta

C. Hylobates lar and Pongo pygmaeus

D. Pan troglodytes and Lemur catta

25.

Which sequence of organization is the same as that of carbon dioxide, the blood and the heart?

A. eggs, sperm, zygote

B. proteins, esophagus, stomach

C. oxygen, stomata, plant

D. water, phloem, leaf

26.


A student was using a dichotomous key to classify theorganisms above.The first set of characteristics is:
I. vertebrate
II. invertebrate
According to the first set of characteristics, which of these would be classified as a vertebrate?
A. / spider
B. / fly
C. / frog
D. / crab

27.

The diagram illustrates how some characteristics of the horse have changed over time. Along with differences in size, what is another anatomical difference between the modern horse and its ancestors?

A. The structure of the tooth has been adapted for eating meat.

B. The size of the molars has decreased.

C. The length of the forefoot has decreased.

D. The number of toes has decreased.

28.


Each region of this diagram represents a collection of organisms or members of a taxonomic level. Region D represents flying mammals. Region A represents birds. Which of the following is most likely the taxonomic level region C represents?
A. / Invertebrates
B. / Birds
C. / Mammals
D. / Vertebrates

29.

Which molecules would be represented in the figure above by the number 2?

A. H20 and O2

B. H2O and CO2

C. Sugars and O2

D. Sugars and CO2

30.

Which diagram represents a system of biological taxonomy showing evolutionary relationships among groups of organisms?
A. /
B. /
C. /
D. /

31.

Students place a plant in a dark and windowless closet for two days. Which of the following will help the plant maintain homeostasis?

A. growing deeper roots

B. using the stored sugars

C. decreasing the stem size

D. losing all of its leaves

32.

The Kaibab squirrel lives on the Kaibab Plateau, north of the Grand Canyon. Another very similar squirrel, the Abert squirrel, lives only south of the Colorado River, on the other side of the Grand Canyon. These two species share a common ancestor that lived many years ago.

In this case, speciation most likely occurred because the two species of squirrels -
A. / utilize different resources
B. / are geographically separated
C. / have different mating behaviors
D. / have different-sized populations

33.