21. Which of the following is not a common feature shared by all metabolic pathways? A) Each pathway contains multiple intermediate products, and there are small
molecular differences between the intermediates. B) Each pathway is regulated to ensure the optimal use of resources and to
maintain the health of the cell. C) Each step within the pathway, or the conversion from one intermediate to the
next, is catalyzed by a nucleic acid with a reactive R group. D) Many pathways are universal among living organisms.
22. A child is born with a rare disease in which mitochondria are missing from certain skeletal muscle cells. Physicians find that the muscle cells function. Not surprisingly, they also find that ______. A) the muscle cells cannot split glucose to pyruvic acid B) the muscles contain large amounts of carbon dioxide following even mild
physical exercise C) the muscles require extremely high levels of oxygen to function D) the muscles contain large amounts of lactic acid following even mild physical
exercise 23. Which statement best describes the relationship between plants and
animals on earth? A) Plants produce O2 and sugars from CO2 B) Animals produce CO2 and H2O from sugars and O2 C) Plants produce CO2 and H2O, and animals produce O2 and sugars and D) Plants produce O2 and sugars and animals produce CO2 and H2O E) None of the above.
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24. The ultimate source of the energy in food is ______. A) producers B) the sun C) ATP D) consumers E) lipids and nucleic acids
25. A researcher planted seeds from four types of quinoa (Types A, B, C, and D) in a greenhouse to determine which type of quinoa grew the tallest. The plants were grown for 10 days and measured. The results are shown below. Choose the data set that demonstrates that Type B quinoa grew the tallest. A) A = 30 cm, B = 21 cm, C= 15 cm, D= 12 cm. B) A = 22 cm, B = 27 cm, C = 11 cm D= 4 cm C) A = 2 cm, B = 5 cm, C= 1 cm, D= 2 cm D) A = 30 cm, B = 12 cm, C= 28 cm, D= 1 cm E) A = 21 cm, B = 12 cm, C= 20 cm, D= 15 cm
26. A replicated chromosome consists of two ______ joined at the _____.
A) diploid genes; locus B) homologous chromosomes; crossing over point C) genomes; centrosome D) sister chromatids; centromere E) haploid chromosomes; fertilization point
27. Homologous chromosomes ______.
A) are both inherited from the female parent B) are a set of chromosomes that the cell received from one parent C) include only the autosomes D) carry the same versions of all genes E) carry genes controlling the same inherited characteristics
28. In meiosis, how does prophase I differ from prophase II?
A) During prophase I there is one diploid cell; during prophase II there are two haploid cells.
B) During prophase I chromosomes line up single file in the middle of the cell; during prophase II the chromosomes line up in double file in the middle of the cell.
C) During prophase I the chromosomes coil up; the chromosomes are not coiled up during prophase II.
D) In prophase I the sister chromatids are attached; in prophase II the sister chromatids are separated.
29. This diagram of the human life cycle shows that ______. A) meiosis produces a diploid
zygote B) meiosis produces diploid
sperm and egg cells C) fertilization produces a haploid
zygote D) a diploid zygote undergoes
meiosis to produce an adult human
E) None of the above. 30. A couple has two male children. What is the probability that their next child
will be female? A) 100% B) 25% C) 33% D) 50% E) 67% F) 0%
31. How can one recognize polygenic inheritance?
A) A mating between a homozygous and a heterozygous individual produces more than the expected number of offspring expressing the dominant trait.
B) All of the alleles of the gene for that trait are equally expressed. C) The trait varies along a continuum in the population. D) Pleiotropy occurs.
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Please read the following scenario to answer the following question.
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Widow’s peak, a pointed hairline on the forehead, is a genetic trait caused by a somatic dominant allele. It can be traced back through a family’s history using pedigree analysis. The pedigree shown here shows three generations of a family. Individuals shown in gray have a widow’s peak. (W = dominant allele and w = recessive allele)
32. Jonathan’s genotype is _______.
A) WW B) ww C) Ww D) WW or Ww E) impossible to tell
33. Translation converts the information stored in ______ to ______.
A) DNA… RNA B) DNA… a polypeptide C) RNA… DNA D) RNA… a polypeptide E) a polypeptide…. DNA
34. After replication, ______. A) each new DNA double helix consists of two new strands B) each new DNA double helix consists of two old strands C) one new DNA double helix consists of two old strands and the other new DNA
double helix consists of two new strands D) each new DNA double helix consists of one old strand and one new strand
35. What is the smallest number of nucleotides that must be added or
subtracted to change the triplet grouping of the genetic message? A) one B) two C) three D) four
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36. What is the ultimate source of all diversity? A) natural selection B) sexual recombination C) meiosis D) mutation
Please read the following scenario to answer the following two question(s). While working with cultured mouse cells, a researcher unknowingly treated the cells with a mutagen that causes the deletion or insertion of individual nucleotides in DNA. Subsequently, she isolated and cultured a single cell from this group. She noticed that the progeny of this cell were not producing a certain protein and that this affected their survival. 37. The mutation would be most harmful to the cells if it resulted in ______.
A) a single nucleotide insertion near the start of the coding sequence B) a single nucleotide deletion near the end of the coding sequence C) a single nucleotide in the middle of an intron D) deletion of a triplet near the middle of the gene
38. The mutation that resulted from her accident was probably ______.
A) an amino acid substitution B) a loss in regulation of gene expression C) one that changed the triplet grouping of the genetic message D) an error in translation
39. Why doesn’t your tongue grow hair?
A) because the genes for keratin have been deleted from the cells of your tongue
B) because different genes are expressed in different tissues C) because skin cells have extra DNA that encodes hair proteins D) because saliva prevents hair from growing E) because tongue cells contain enzymes that destroy the genes for hair
production 40. Which of the following are homologous structures?
A) the forelimb of a dog and the hindlimb of a cat B) the mouth of a mosquito and the beak of a hummingbird C) wings of a butterfly and wings of a sparrow D) the forelimb of a dog and the forelimb of a cat
