1. Conceptually speaking, order the following structures from smallest to largest: DNA, gene, genome, chromosome, nucleotide.
a. DNA, gene, genome, chromosome, nucleotide
b. genome, DNA, chromosome, nucleotide, gene
c. nucleotide, gene, DNA, chromosome, genome
d. gene, chromosome, nucleotide, genome, DNA
2. Which of the following are living things? DNA, gene, genome, chromosome, cell, nucleotide.
a. DNA, gene, and genome
b. chromosome and DNA
c. cell, chromosome, and genome
d. cell only
3. Which structures are considered the “basic unit of life” and the “basic unit of heredity”?
a. The basic unit of life is the cell, and the basic unit of heredity is the gene.
b. The basic unit of life is the cell, and the basic unit of heredity is the nucleotide.
c. The basic unit of life is the protein, and the basic unit of heredity is the nucleotide.
d. The basic unit of life is DNA, and the basic unit of heredity is the gene.
4. What is a gene?
a. the protein that results after translation is complete
b. a segment of DNA that is three nucleotides long
c. a segment of DNA that carries a unit of information
d. one arm of a single chromosome
5. Genes exist in pairs in cells. Where did each member of a pair of genes originate?
a. one from each parent’s gametes
b. the duplication of chromosomes during the S phase
c. crossing over during prophase I
d. the growth during G1 produced each member of the pair
6. What is wrong with this example? A heterozygous pea plant produces yellow seeds and its genotype is Yg, where Y represents the dominant yellow seed allele and g represents the recessive green seed allele.
a. The genotype should be presented as Gg because green is the recessive trait.
b. A heterozygous pea plant with yellow seeds would have the genotype YY or yy.
c. The correct genotype is Yy because yellow is the dominant trait.
d. The genotype Yg would produce green seeds.
7. Use your newfound knowledge of the inheritance of traits and Punnett Squares to predict the chances that a Gg pea plant producing green pods and a gg pea plant producing yellow pods, when crossed with one another, will produce offspring with yellow pods.
a. There is a 0-percent chance of this cross producing yellow pods.
b. There is a 25-percent chance of this cross producing yellow pods.
c. There is a 50-percent chance of this cross producing yellow pods.
d. There is a 100-percent chance of this cross producing yellow pods.
NOTE: Questions 8–13 refer to the offspring of the plant described in question 7.
8. What is the genotype of these offspring?
9. What is the phenotype of these offspring?
10. Is this plant heterozygous or homozygous? Why?
a. Heterozygous—the genotype consists of two different alleles.
b. Heterozygous—the genotype consists of two identical alleles.
c. Homozygous—the genotype consists of two different alleles.
d. Homozygous—the genotype consists of two identical alleles.
11. What dominant alleles, if any, does this plant have in its cells?
12. What recessive alleles, if any, does this plant have in its cells?
13. Where are the alleles located in this plant?
a. on the golgi apparatus
b. in the nucleolus
c. on the amino acids
d. in the DNA
14. If purple flowers are dominant on pea plants, what alleles does a pea plant have if it produces purple flowers?
c. PP only
d. PP and Pp
15. A particular pea plant has the following characteristics:
height: tall, with a genotype of Tt seed
texture: wrinkled, with a genotype of rr pod
color: green, with a genotype of pp (purple is the dominant color)
Is the genotype for the color of the pea plant heterozygous or homozygous?
c. neither of the above
16. What are the two general types of chromosomes in human cells?
a. autosomes and sex chromosomes
b. homozygous and heterozygous
c. dominant and recessive
d. X and Y
17. How many autosomes and sex chromosomes does a human male liver cell have?
18. How many autosomes and sex chromosomes does a human egg have?
19. How many Y chromosomes does a woman have in her cells?
20. Normal human lung cells contain two copies of chromosome 3. Together these are called a pair of homologous chromosomes. How are homologous chromosomes similar and how are they different from one another?
a. Homologous chromosomes are identical to each other in every way.
b. They have the same genes, but they are located in different places on the chromosome.
c. They have the same length and shape but carry different genes.
d. They have the same length and shape and carry the same genes but may have different alleles.
21. Is it possible to have an autosomal sex-linked gene?
22. Is it possible to have a dominant recessive trait?
23. Neither Mr. nor Mrs. Abbott has the genetic disease cystic fibrosis, but their newborn son, James, does. Based on this information alone, is it most likely that cystic fibrosis is an autosomal dominant, autosomal recessive, or sex-linked genetic disease?
a. autosomal dominant
b. autosomal recessive
d. none of the above
24. The glucose dehydrogenase gene is located on chromosome 1 in humans. Is this an autosomal or a sex-linked gene?
c. neither of the above
25. What holds the nucleotides in one strand of DNA together?
a. hydrogen bonds between adjacent nucleotides
b. covalent bonds between adjacent nucleotides
c. ionic bonds between adjacent nucleotides
d. electron bonds between adjacent nucleotides
26. If the sequence of one strand of a DNA molecule is AGTGCCAGATCGCATCC, what does the other strand of the molecule look like?
27. How are these two strands held together in the double helix?
a. hydrogen bonds between base pairs
b. covalent bonds between base pairs
c. ionic bonds between base pairs
d. electron bonds between base pairs
28. When does DNA replication occur?
a. during the G1 phase of interphase
b. during the S phase of interphase
c. during the G2 phase of interphase
d. during prophase
29. Why do cells duplicate (replicate) their DNA?
a. to have enough DNA available to act as a template for RNA during transcription
b. to reduce the number of chromosomes present in each gamete
c. to ensure genetic variability among all cells
d. so that each of the daughter cells formed during mitosis will have an identical copy of the DNA
30. How is information stored and coded in DNA and genes?
a. in sets of three nucleotides called codons
b. in amino acids that are bonded together to form proteins
c. as mRNA, tRNA, and rRNA
d. by an RNA polymerase
31. Put the following in the correct sequence to show the general path in which genetic information “flows” from genes to traits: DNA, protein, RNA, trait, transcription, translation.
a. DNA, translation, transcription, protein, RNA, trait
b. transcription, DNA, translation, protein, RNA, trait
c. DNA, transcription, RNA, translation, protein, trait
d. DNA, RNA, transcription, translation, protein, trait
32. What is meant by the term genetic code?
a. the DNA in cells that carries information in genes to assemble proteins
b. all DNA and RNA found in cells
c. the proteins assembled during translation
d. the base pairing rules: A to T and G to C
33. What are the subunits from which DNA, RNA, and proteins are built?
a. uracil, thymine, and methionine
b. DNA and RNA = nucleotides, protein = amino acids
c. histones and nucleosomes
d. simple sugars
34. Compare and contrast transcription and translation.
a. In translation, RNA makes a copy of DNA in the nucleus; and in transcription, the RNA provides the code to assemble proteins in the ribosome.
b. In transcription, RNA takes DNA from the nucleus to the ribosome; and in translation, the DNA separates into proteins.
c. In transcription, DNA makes a copy of RNA in the nucleus; and in translation, the DNA provides the code to assemble proteins in the mitochondria.
d. In transcription, RNA makes a copy of DNA in the nucleus; and in translation, the RNA provides the code to assemble proteins in the ribosome.
35. What does the phrase differential gene expression mean?
a. Each cell has different genes present in its genetic code.
b. The protein coded for by a single gene may change in different cells.
c. Only some genes are turned on in each particular cell.
d. Different genes may code for the same protein in different cells