TSSM BIOLOGY 2019 Unit 3 Key Topic Test 2 – Nucleic acids and proteins QUESTION BOOK

The monomers of nucleic acids are called A. amino acids B. ribose sugars C. nucleotides D. nitrogenous bases Question 2 Nucleic acids occur in 2 forms, RNA and DNA. One significant difference between them is A. DN ...

The monomers of nucleic acids are called A. amino acids B. ribose sugars C. nucleotides D. nitrogenous bases Question 2 Nucleic acids occur in 2 forms, RNA and DNA. One significant difference between them is A. DNA is single stranded B. RNA is found only in the nucleus C. DNA has 4 bases D. RNA contains uracil Question 3 Nucleic acids encode instructions for the synthesis of proteins in cells. These instructions are found in the A. ribosomes B. order of nitrogenous bases in DNA C. protein molecules formed during transcription D. mRNA made during translation Question 4 The entire set of proteins that can be expressed by a genome is the A. proteomics B. proteome C. protein load D. genomics 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 4 of 10 Question 5 A tertiary protein structure can be considered functional because it has A. both double helix and beta pleated sheets B. a specific three-dimensional shape C. hydrogen and disulphide bonds D. the ability to be used up when catalysing enzyme-based reactions Question 6 A single strand of amino acids formed during protein synthesis could be known as a A. protein structure B. a polypeptide chain C. polymerisation D. protein monomer Question 7 When peptide bonds are formed in protein synthesis, water is produced as a by-product. This is due to the bonding of A. a carboxyl group with an R group B. a nitrogenous base with an amino group C. an amino acid with a carboxyl group D. a carboxyl group with an amine group Question 8 Proteins and DNA are similar in that they both A. have nitrogenous bases B. form peptide bonds through hydrolysis reactions C. have monomers that undergo condensation polymerisation D. form a unique 3D structure with specific active sites Question 9 The genetic code is found in all living organisms on earth. It is used as an information molecule that codes for amino acids through a degenerate triplet code system. Degenerate in this instance means A. the DNA code is universal B. more than one triplet codes for an amino acid C. DNA degenerates over time into triplets D. all life on earth uses the triplet code system to code for proteins 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 5 of 10 Question 10 RNA processing refers to A. the splicing of RNA in prokaryotes to remove introns B. the removal of exons from mRNA C. the adding of a poly A cap and methyl tail to mRNA D. changing pre-mRNA to prepare for translation Question 11 Transcription refers to the synthesis of mRNA in the nucleus of a eukaryotic cell. During transcription you would expect that A. there would be an increase in the amount of water in the nucleus B. mRNA would move into the nucleus in large amounts C. the amount of free uracil in the nucleus would increase D. the amount of DNA in the nucleus would double as the DNA is split in transcription Question 12 Prokaryotes undergo transcription and translation to produce proteins however the process is much faster. This is because A. prokaryotes are much smaller than eukaryotes and do not need as many proteins B. amino acids are closer together in prokaryotes C. mRNA is produced without the need for splicing D. prokaryotes have plasmids Question 13 Amino acids have variable R groups attached to the molecule. Source modified from: http://academic.pgcc.edu The variability of the R group allows for any protein that is produced to have A. bonding between R groups creating beta helix shapes in secondary structures B. hydrophobic or hydrophilic areas depending on its structure C. a functional 3-dimensional secondary structure D. an amino acid active site with a unique specific shape 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 6 of 10 Question 14 Once mRNA has been formed during transcription it leaves the nucleus and connects with a ribosome. At this stage enzymes designed to protect the cell from viral infection begin to break apart the mRNA. To protect the production of the protein the mRNA has A. codons matching tRNA anticodons B. a Poly A tail C. polypeptide bonds D. alternate splicing Question 15 mRNA in ribosomes briefly bonds with a tRNA molecule to drop off the next amino acid required to make a protein. The part of the mRNA that matches with the tRNA is called A. an amino acid B. a codon C. an anticodon D. a monomer 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 7 of 10 SECTION B - Short-answer questions Instructions for Section B Answer all questions in the space provided. Write using a blue or black pen. Question 1 DNA and RNA molecules encode for protein synthesis through the transcription of DNA to mRNA and the translation of mRNA to amino acids. While both DNA and RNA are essential to producing proteins, they are very different molecules a. Compare the characteristics of DNA to RNA in the table below: Characteristic DNA RNA Shape Number of strands Type of sugar Bases b. There are 3 forms of RNA. Name each form and state the function of each: c. Proteins perform a range of functions throughout an organism including catalysts, messenger molecules, support structures, transport proteins etc yet all proteins are created in the same way through the protein synthesis process. Explain why proteins made in the same way can have multiple functions? _____________________________________________________________________ _____________________________________________________________________ 4 + 3 + 2 = 9 marks Name Function 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 8 of 10 Question 2 The structure shown below shows an image of a section of protein Source modified from: https://owlcation.com a. The image of a protein shows 2 different structures. Name structure A. _____________________________________________________________________ _____________________________________________________________________ b. Both structure A and B are formed from amino acids joined together by peptide bonds. Name the level of hierarchy of these shapes. _____________________________________________________________________ _____________________________________________________________________ c. What type of bonds hold these structures together in these shapes? _____________________________________________________________________ _____________________________________________________________________ d. The protein is not thought to be functional when it is at the level in question 2b. Explain why? _____________________________________________________________________ _____________________________________________________________________ 1 + 1+ 1 + 2 = 5 marks A B 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 9 of 10 Question 3 The diagram below shows monomers of protein about to react Source modified from https://encyclopedia2.thefreedictionary.com a. What is the name of the reaction that is about to occur? _____________________________________________________________________ _____________________________________________________________________ b. What is formed as a by-product of this reaction? _____________________________________________________________________ _____________________________________________________________________ c. What is the name of the monomer? _____________________________________________________________________ ____________________________________________________________________ d. What is the name of the bond that is formed through this reaction? _____________________________________________________________________ _____________________________________________________________________ e. A similar reaction occurs in DNA and RNA to build those molecules. What is the name of the monomer of DNA? _____________________________________________________________________ _____________________________________________________________________ 1 + 1 + 1 +1 + 1= 5 marks 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 10 of 10 Question 4 The diagram below shows codons of mRNA and the amino acids they code for. Source modified from http://www2.sluh.org a. What does degenerate triplet code mean? _____________________________________________________________________ _____________________________________________________________________ b. What is the DNA triplet code that is transcribed to code for the amino acid MET? _____________________________________________________________________ c. Translate the following mRNA section: AUGCUUAAUUGA _____________________________________________________________________ ____________________________________________________________________ d. Pre-mRNA undergoes processing before it is sent out of the nucleus. What occurs during the RNA processing stage? _____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ e. Why does RNA processing occur?