BIO 1330 final exam review ( ch 10 - 19) PDF

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final exam review
covers the second half the class
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BIO 1330 – Final Exam Review (10-19) Chapter 10 – photosynthesis •

Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? o ATP and NADPH

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When oxygen is released as a result of photosynthesis, it is a direct by product of splitting water molecules.

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Which of the following statements best describes the relationship between photosynthesis and respiration? o Photosynthesis stores energy in complex organic molecules. o Respiration releases this energy

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Chlorophylls absorb most light in which colors of visible range? o Blue and red

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What event accompanies energy absorption by chlorophyll? o An electron is excited

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As electrons are passed through the system of electron carriers associated with photosystem II, they lose energy. What happens to this energy? o It is used to establish and maintain a proton gradient.

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The electrons of photosystem II are excited and transferred to electron carriers. From which molecular structure do the photosystem II replacement electrons come? o Water

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What is the main purpose of light-dependent reactions of photosynthesis?

o To produce NADPH and ATP •

Which of the events listed below occurs in the light reactions of photosynthesis? o Light is absorbed and funneled to reaction center chlorophyll A.

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Which statement describes the functioning of photosystem II? o The electron vacancies in P680+ are filled by electrons derived from water.

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Which of the following are directly associated with photosystem I? o Receiving electrons from the thylakoid membrane electron transport chain

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Which process is most directly driven by light energy? o Removal of electrons from chlorophyll molecules

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Which of the following statements best represents the relationships between the light reactions and the Calvin cycle? o The light reactions provide ATP and NADPH to the Calvin cycle, and the Calvin cycle returns ADP, P+, and NADP+ to the light reactions

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Photorespiration generates carbon dioxide and consumes ATP and oxygen

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Where do the enzymatic reactions of the Calvin cycle take place? o Stroma of the chloroplasts

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What is the primary function of the Calvin cycle? o Synthesizing simple sugars from carbon dioxide

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Reactions that require CO2, take place in the Calvin cycle alone.

Chapter 11 – gene expression

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A cell with membrane bound proteins that selectively bind to a specific hormone is called that hormone’s target cell.

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Which of the following is characteristic of a steroid hormone action? o Internal receptor binding

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What does it mean to say that a signal is transduced? o The physical form of the signal changes from one form to another

Chapter 12 – cell cycle •

In eukaryotic cells, chromosomes are composed of DNA and proteins.

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The mitotic spindle is a microtubular structure that is involved in separation of sister chromatids.

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Mitosis separates chromosomes. Cytoplasm is divided between two daughter cells by cytokinesis.

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Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on the other side of the cell plate. This cell is most likely a plant cell in the process of cytokinesis.

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Which of the following. Does not occur during mitosis? o Replication of the DNA

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If a ell has accumulated DNA damage, it is unlikely to pass the G2 checkpoint.

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Regulatory proteins that prevent a cell from entering S phase under conditions of DNA damage are also known as tumor suppressors.

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Proteins that are involved in the regulation of the cell cycle and that shows fluctuations during the cell cycle are called cyclins.

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A cyclin activates a CdK molecule when it is in sufficient concentration.

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The product of the p53 gene inhibits the cell cycle

Chapter 13 – cell cycle •

After telophase I of meiosis, the chromosomal make up of each daughter cell is haploid, and the chromosomes are each composed of two chromatids.

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How do cells at the completion of meiosis compare with cells that are in prophase of meiosis I? o They have half the number of chromosomes and is ¼ the amount of DNA.

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Sister chromatids separate from each other during mitosis and meiosis II.

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Independent assortment of chromosomes occurs during meiosis I only.

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Which of the following occurs in meiosis but not mitosis? o Synapsis of chromosomes

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Somatic cells of roundworms have four individual chromosomes per cell. How many chromosomes would you expect to find in an ovum from a roundworm? o 2

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Which of the following can occur by the process of meisosis by not mitosis? o Diploid cells form haploid cells

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In meiosis, homologous chromosomes are separated during anaphase I.

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Crossing over normally takes place during which of the following processes? o Meiosis I

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Homologous pairs of chromosomes align opposite to each other at the equator of a cell during metaphase I of meiosis.

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If meiosis produces haploid cells, how is the diploid number restored for those organisms that spend most of their life cycle in diploid state? o Fertilization

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Independent assortment of chromosomes is a result of the random way each pair of homologous chromosomes line up at the metaphase plate during meiosis I.

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Which is the smallest unit contain the entire human genome? o One male somatic cell

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What is the most common source of the extra chromosomes 21 in an individual with down syndrome? o Nondisjunction in the mother

Chapter 15 – DNA replication •

In analyzing the number of different bases in a DNA sample, which result would be consistent with the base pairing rule? o A + G = C + T

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Of the following, which is the most current description of a gene? o a DNA sequence that is expressed to form a functional product: either RNA or polypeptide

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DNA is synthesized through a process known as semiconservative replication

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What provides the energy for the polymerization reactions in DNA synthesis? o the deoxyribonucleotide triphosphate substrates

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What is a major difference between eukaryotic DNA replication and prokaryotic DNA replication? o prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have multiple origins of replication

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The leading and lagging strand differ in that the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction.

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What is the role of DNA ligase in the elongation of the lagging strand during DNA replication? o it joins Okazaki fragments together

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Which of the following help(s) to hold the DNA strands apart while they are being replicated? o single-strand DNA binding proteins

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What is a telomere? o the ends of linear chromosomes

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Which one of the following is least likely to cause mutations in DNA? o light from an incandescent bulb

Chapter 16 - genetics •

In the process of transcription, RNA is synthesized.

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Which of the following is NOT synthesized from a DNA template? o amino acids

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Which of the following is an exception to the central dogma? o the discovery of RNA viruses that synthesize DNA using reverse transcriptase

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The statement "DNA → RNA → Proteins", is known as the central dogma.

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According to the central dogma, what molecule should in the blank? DNA → _____ → Proteins o mRNA

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How does the simple primary and secondary structure of DNA hold the information needed to hold information needed to code for the many features of multicellular organism? o the base sequence of DNA carries the information needed to code for proteins

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What does is mean when we say the genetic code is redundant? o More than one codon can specify the addition to the same amino acid

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Which of the following nucleotide triplets best represents a codon? o A triplet in the same reading frame as an upstream AUG

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Which of the following is directly related to a single amino acid? o The three-base sequence of mRNA

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Codons are part of the molecular structure of mRNA.

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Which one of the following is true? o A codon is the basic unit of the genetic code.

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The mutation resulting in sickle cell disease changes one base of DNA so that a codon now codes for a different amino acid, making it an example of a missense mutation.

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A mutation that results in a premature termination of translation is a nonsense mutation.

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Why might a point mutation in DNA make a difference in the level of a protein's activity? o It might substitute a different amino acid in the active site

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A nonsense mutation in a gene introduces a premature stop codon into the mRNA.

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A frameshift mutation could result from either an insertion or a deletion of a base.

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Which of the following mutations is likely to cause the most dramatic phenotypic change? o A single nucleotide deletion in an exon for an active site

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Which of the following DNA mutations is most likely to damage the protein it specifies? o A base-pair deletion

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Which small-scale mutation would be most likely to have a catastrophic effect on the functioning of a protein? o A base deletion near the start of a gene

Chapter 17 – gene to protein •

In eukaryotic cells, transcription cannot begin until several transcription factors have bound to the promoter.

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Which of the following processes is central to the initiation of transcription in bacteria? o Binding of sigma to the promoter

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Eukaryotes have three nuclear RNA polymerases. the primary function of RNA polymerase II is transcription of protein coding genes.

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What is responsible for termination of transcription in eukaryotic protein coding genes? o A polyadenylation, or poly(A), signal

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A ribozyme is a RNA with catalytic activity

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Which one of the following statements about RNA processing is true? o Ribozymes may function in RNA splicing There should be a strong positive correlation between the rate of protein synthesis and the number of ribosomes. Ribosomes can attach to prokaryotic messenger RNA before transcription is complete. A particular triplet of bases in the coding sequence of DNA is AAA. the anticodon on the tRNA that binds the mRNA codon is UUU.

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Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on specificity in the binding of anticodon and the attachment of amino acids to tRNAs. • There are 61 mRNA codons that specify an amino acid, but only 45 tRNAs. this is best explained by the fact that the rules for base pairing between the third base and tRNA are flexible. • What ensures that the correct amino acid is added during translation? o The anticodon of a properly formed aminoacyl tRNA • The anticodon of a particular tRNA molecule is complementary to the corresponding mRNA codon • Translation directly involves mRNA, tRNA, ribosomes, and GTP. • Which of the following is the first event to take place in translation in eukaryotes? o The small subunit of the ribosome recognizing and attaching to the 5 cap of mRNA • Translation requires mRNA, tRNA, and rRNA. • During elongation, which site in the ribosome represents the location where a codon is being read? o A site • How does termination of translation take place? o a stop codon is reached Chapter 19 – gene expression •

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Muscle cells differ from nerve cells mainly because they express different genes.

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Which of the following allows more than one type of protein to be produced from one gene? o Alternative forms of RNA splicing

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In a nucleosome, the DNA is wrapped around histones.

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If you were to observe the activity of methylated DNA, you would expect it to have turned off or slowed down the process of transcription.

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DNA methylation and histone acylation are examples of epigenetic phenomena.

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Cell differentiation always involves the production of tissue-specific proteins, such as muscle actin.

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Which of the following statements describes a eukaryotic chromosome? o a single linear molecule of double-stranded DNA plus proteins

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Histone acetyl transferases exert their effect on gene activity by neutralizing positive charges on the lysines of histones.

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In eukaryotes, general transcription factors bind to other proteins or to the TATA box.

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Regulatory transcription factors influence the assembly of the basal transcription complex.

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The reason for difference in the sets of proteins expressed in a nerve and a pancreatic cell of the same individual is that nerve and pancreatic cells contain different sets of regulatory proteins.

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Of the following, which is the most current description of a gene? o A DNA sequence that is expressed to form a functional product: either RNA or polypeptide

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The phenomenon in which RNA molecules in a cell are destroyed if they have a sequence complementary to an introduced double-stranded RNA is called RNA interference.

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Alternative RNA splicing can allow the production of proteins of different size and functions from a single mRNA.

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Proto-oncogenes stimulate normal cell growth and division.

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The normal function of a tumor suppressor gene is to prevent progression of the cell cycle unless conditions are right for moving forward.

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The predominant mechanism driving cellular differentiation is the difference in gene expression....