Exam 1 Review Course: BIO/GEN 313 SI Leader: Anna Rowzee Date: 09/13/21
This STUDY GUIDE is for your use in preparing for the exam.
This resource does not reflect the questions or format you will see on the exam.
The questions in this study guide are purposefully broad so that you are able to use your recall skills to answer.
This resource is to help you identify what you need to work on more. If there is a concept that you still do not understand, it would be prudent to go back and read that section in the textbook.
There is no guarantee that everything in this resource will be found on the test, nor will everything on the test be found in this resource.
The concepts reviewed in this guide are what I believe will be most helpful to you based on my own experience and past SI sessions. That being said, I do not specifically know what will be on the exam and cannot tell you, nor can I tell you how this study guide compares to the exam you will take.
If you have any questions feel free to contact your professor by email or me through the SI website.
Good Luck!
-Anna :)
1. What is the correct order from largest to smallest?
a. genome>cell>DNA strand>gene>chromosome>nucleotide b. cell>genome>chromosome>DNA strand>gene>nucleotide c. chromosome>genome>DNA strand>cell>nucleotide>gene d. cell>genome>chromosome>gene>nucleotide>DNA strand
2. Name and briefly describe the three subfields of genetics:
Transmission genetics - how genes are transmitted from one generation to the next
Molecular genetics - what molecules are involved in gene expression Population genetics - how do genes and their alleles change in a group of individuals of a population
3. For the following, determine whether the statement is TRUE or FALSE regarding the implications of all organisms having similar genetic systems:
a. All life forms are genetically related TRUE
b. A gene existing in one organism will exist in all other organisms FALSE c. Findings related to the genes of one organism can often be applied to
other organismsTRUE
d. Genes from one organism can often exist in and be expressed by another organismTRUE
e. There is no difference between the genome of one organism and the genome of another organismFALSE
For questions 4-9, choose the answer that best fits the theory of inheritance listed:
(For extra practice, label the other two theories for each question with their theory name) 4. Pangenesis is:
a. The modern theory that all cells contain a complete set of DNA (the entire genome)
b. The theory that genetic information travels from all different parts of an organism’s body to the reproductive organs to form the gametes
c. The theory that genes from each parent mix together so that when the reproductive cells combine the genes mingle together and their origins become indistinguishable
5. Inheritance of acquired characteristics says:
a. traits that are developed by an individual over their lifetime are passed onto their offspring
b. all life is composed of cells, and cells themselves only come from existing cells
c. traits from the parents are inherited according to specific principles
6. Preformation is the idea that:
a. Genetic information travels from all parts of the body to the reproductive organs
b. A miniature being called a homunculus resides in the sex cell from one or the other parent, therefore all traits are inherited from only one parent c. Genes from the parents comingle together are can never be separated out
or distinguished
7. The theory of blending inheritance says:
a. Traits are inherited according to specific principles
b. Genetic information travels to the reproductive organs from all parts of the body
c. That genes from each parent mix together so that when the reproductive cells combine the genes mingle together and their origins become
indistinguishable
8. Germ-plasm theory can be explained as:
a. All cells contain a complete set of genetic information
b. All life is composed of cells and cells themselves only arise from existing cells
c. Genes from the parents blend together until the parent genes cannot be separated out again
9. The principle of Mendelian genetics is:
a. All cells contain a complete set of genetic information
b. Cells are the fundamental unit of life and all new cells must come from existing cells
c. Traits are inherited according to specific principles (in a predictable pattern)
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10.Match the scientists’ with the discoveries listed. Each answer will only be used once, some will not be used at all:
a. Kossel
b. Watson and Crick c. Levene
d. Miescher
e. Hershey and Chase
f. Avery, McLeod, and McCarty
g. Griffith
h. Franklin and Wilkins i. Chargaff
__H__Took x-ray diffraction pictures used in determining the structure of DNA __E__ Identified DNA as the genetic material in bacteriophage
__I__ Discovered regularity in the ratios of different bases in DNA
__F__ Determined that DNA is responsible for transformation in bacteria __B__ Worked out the helical structure of DNA by building models
__G__ Demonstrated that heat-killed material from bacteria could genetically transform live bacteria
11. According to Chargaff’s Rule, which of the following statements is correct?
a. (A + T) / (C + G) = 1.0 b. A + T = G + C
c. (A + G) / (C + T) = 1.0 d. A / C = G / T
12.Varying forms of a gene are called:
a. Copies b. Alleles c. Variants d. Genotypes
For questions 13-15, determine whether the statement describes primary, secondary, or tertiary DNA structure:
13. A linear sequence of DNA nucleotides.
a. Primary structure b. Secondary structure c. Tertiary structure
14.The supercoiling and packing of DNA into a chromosome.
a. Primary structure b. Secondary structure c. Tertiary structure
15.The double-stranded DNA helix (two DNA strands joined into a helix).
a. Primary structure b. Secondary structure c. Tertiary structure
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16.What are the primary differences between an RNA nucleotide and a DNA nucleotide? (circle each correct answer)
a. Type of sugar (Ribose vs. deoxyribose)
b. One has a phosphate group and one has a carboxyl group c. One has uracil and one has thymine
d. One has an OH group on the 2’ carbon and one has H e. One has a 6-carbon sugar one has a 5-carbon sugar
17. Which of the following are pyrimidines (choose the best, most complete answer) a. Thymine, adenine
b. Thymine, cytosine, uracil c. Adenine, guanine, uracil d. Cytosine, guanine
18.Trueor False: Complementary DNA strands align antiparallel to each other.
19.Suppose that you isolate a sample of nucleic acid from a virus and want to determine more information about this material. You analyze the sample and find it is 25% adenine, 20% guanine, 30% cytosine, 0% thymine, and 25% uracil.
Based on this information, pick the best answer from the options below.
The material sampled is:
a. A single strand of DNA b. A double strand of DNA c. A single strand of RNA d. A double strand of RNA
20.True orFalse: Euchromatin is more condensed than heterochromatin, therefore heterochromatin is transcribed more frequently.
21.Trueor False: Heterochromatin is found primarily at the centromeres and telomeres of chromosomes.
22.The nucleosome consists of: (choose the best answer)
a. Two wraps of DNA, 2H1, 2 H2A, 2HB, 2H3, and 2H4 histones
b. Two wraps of DNA, 1H1, 2 H2A, 2HB, 2H3, and 2H4 histones, linker DNA c. Two wraps of DNA, 1 H1, 2 H2A, 2HB, 2H3, and 2H4 histones
23.If each nucleosome encompasses approximately 200bps of DNA, how many nucleosomes would you expect to find in a DNA strand containing 48 million base pairs (48,000,000bp)? How many histone proteins (including H1) would be associated with this DNA?
a. 240,000 nucleosomes; 2,160,000 histone proteins b. 240,000 nucleosomes; 1,920,000 histone proteins c. 12,000,000 nucleosomes; 3,000,000 histone proteins
24.Which theory of replication is the correct?
a. Conservative - The entire double-stranded DNA molecule serves as a template for a whole new molecule of DNA, resulting in one original parent strand and one entirely new strand.
b. Semi-conservative - The two nucleotide strands unwind and each serves as the template for a new strand of DNA, resulting in two helices with one parent strand each.
c. Dispersive - Both nucleotide strands break down into fragments and the pieces serve as templates, resulting in two new helices that contain both parent and new DNA.
25.True orFalse: The leading strand in DNA replication is comprised of Okazaki fragments.
26. Match the proteins below to their functions in DNA replication:
_C_ breaks hydrogen bonds between parent strands A. DNA Polymerase III _F_ bind to separated strands to keep them from
rebonding
B. DNA Polymerase I
_D_ relieves the pressure caused upstream of the fork by the unwinding of the helix
C. DNA helicase
_E_ lays down the RNA primer for DNA polymerase
III to start building off of D. DNA gyrase (topoisomerase) _A_ adds new nucleotides to the 3’ end of the
growing DNA strand
E. Primase
_B_ removes RNA nucleotides laid down by primase (after the new nucleotides have been added) and replaces these single RNA nucleotides with DNA nucleotides
F. Single-stranded binding proteins
_G_ joins the breaks between Okazaki fragments after the RNA primers are removed
G. DNA ligase
27. Identify the location and function of the RNA molecule classes below:
a. Ribosomal RNA (rRNA)
Found in the cytoplasm; it makes up structural and functional components of ribosomes.
b. Messenger RNA (mRNA)
Found in the nucleus and cytoplasm; it carries the genetic code to produce proteins.
c. Transfer RNA (tRNA)
Found in the cytoplasm; it brings amino acids to the ribosome for protein synthesis.
28.What are the three requirements of transcription (from your lecture slides)?
1) Template DNA strand 2) Nucleotides
3) Transcription machinery
29.True orFalse: RNA synthesis requires a primer.
30.True orFalse: An RNA molecule is transcribed from both DNA strands at the same time.
31.Trueor False: RNA is comprised of rNTPS, DNA is comprised of dNTPs.
32. List the three stages of transcription below and briefly summarize each stage.
1) Initiation - RNA polymerase binds to the promoter region of DNA and forms the transcription bubble.
2) Elongation - RNA polymerase cleaves two phosphates from rNTP and adds the nucleotide to the 3’ end of the growing RNA.
3) Termination - occurs by either rho-independent termination (a string of uracil stalls RNA poly so a hairpin can form, which destabilized the RNA-DNA connection and causes them to separate) or rho-dependent termination (uses a rho factor to hairpin a complementary section of RNA(the terminator).
33. What is the difference between the template DNA strand and the nontemplate DNA strand in transcription?
The template strand is the DNA strand that is transcribed into RNA (the new RNA is built off the template) and the nontemplate (coding) strand is the one that is not transcribed (it will be identical to the new RNA, except for uracil
replacing thymine).
34.Trueor False: Different genes may be transcribed from either DNA strand.
35.What is the difference between exons and introns? How was it determined that introns are removed in RNA processing?
Introns are parts of the pre-mRNA that are not needed to produce a protein, so they are removed. Exons are the remaining pieces that are needed to produce a protein and make up the mature mRNA.
This was determined by lining up mature mRNA with the DNA it came from. Scientists found that regions of the DNA strand did not match up with the mature mRNA strand, so they inferred that there must be material removed from the mRNA between transcription and mRNA leaving the nucleus.
36. Trueor False: A gene is a DNA sequence that codes for exons and introns.
37.What are the two additions made to the mRNA prior to it leaving the nucleus?
Addition of 5’-cap and poly(A) tail.
38.Trueor False: Alternative splicing allows for more than one protein to be produced from a single gene.
39.Trueor False: Proteins are polymers composed of amino acids joined together by peptide bonds.
40.Explain how tRNA functions as a transporter for amino acids.
tRNA molecules have an anti-codon that codes for a specific acid, which allows them to pair with an amino acid with a specific codon and bring that amino acid to the ribosomes for protein assembly.
41.Trueor False: The anticodon on a tRNA is on the opposite end of the molecule from the amino acid binding site.
42.Which below correctly describes the genetic code?
a. Singlet code - one base = one amino acid
b. Doublet code - two bases code for each amino acid c. Triplet code - three bases code for each amino acid
43. Using the codon table on the next page, decode the following RNA and write their corresponding amino acid sequences:
a. 5’ -AUGUCAUCCAAGGUC- 3’
Met-Ser-Ser-Lys-Val b. 5’ -AUGGCCACUCCAAGG- 3’
Met-Ala-Thr-Pro-Arg
c. 5’ -AUGCUUCCUAGAGAA- 3’
Met-Leu-Pro-Arg-Glu
44. What is the “wobble position” relating to codons?
The less strict binding of the third nucleotide in a codon that allows some amino acids to be coded for by more than one codon. (example: CAU and CAC both code for Histidine).
45. Fill in the blank: Through wobble, one __anticodon__ can pair with more than one __codon__.
46.Trueor False: Synonymous codons are codons that have different sequences yet still code for the same amino acid.
47. Translation takes place in the __ribosomes__ of the cell.
48.What are the four steps of translation?
1) Binding of amino acids to tRNAs 2) Initiation of translation
3) Elongation (of the protein) 4) Termination
49. What are the codon and anticodon for Methionine? (Make sure to label the 3’
and 5’ ends of both).
Codon: 5’ -AUG -3’
Anticodon: 3’ -UAC- 5’
50.Make a bulleted list of topics you believe you need to review further after completing this worksheet.
