University of Canterbury BIOL/BCHM 111 Cell Biology Test 2023

UNIVERSITY OF CANTERBURY BIOL/BCHM 111 CELL BIOLOGY AND BIOCHEMISTRY TEST 2023 TIME ALLOWED: 60 MINUTES STUDENT ID NUMBER: SURNAME (IN BLOCK LETTERS): FIRST NAMES: 1. WRITE YOUR NAME ON THE QUESTION PAPER IN THE SPACE PROVIDED BELOW 2. Do not open this question sheet until the test starts. 3. This t...

UNIVERSITY OF CANTERBURY BIOL/BCHM 111 CELL BIOLOGY AND BIOCHEMISTRY TEST 2023 TIME ALLOWED: 60 MINUTES STUDENT ID NUMBER: SURNAME (IN BLOCK LETTERS): FIRST NAMES: 1. WRITE YOUR NAME ON THE QUESTION PAPER IN THE SPACE PROVIDED BELOW 2. Do not open this question sheet until the test starts. 3. This test consists of short answer questions – plan to spend ~ 1 minutes/mark 4. Answer all questions in the space provided. Clearly drawn and labelled diagrams should be used to illustrate your answers where appropriate 5. Use the back of the page if necessary, but clearly indicate if you have done this. Mark /60 1a) Water is a compound that can form many hydrogen bonds. Draw and label an example of a hydrogen bond between two water molecules. (3 marks) b) The structure of ethanol is shown below. Find and label an example of a polar and non-polar bond. (1 marks) c) Describe two differences in the characteristics of water and ethanol that are due to the contribution of hydrogen bonds. (2 marks) d) Compare how you might test for the effectiveness of mask wearing at preventing COVID infection using inductive (discovery) and deductive (hypothesis) reasoning (4 marks) 2a) Briefly describe the biochemistry behind the observation that penguin feet contain unsaturated fatty acids, but coconut oil is rich in saturated fatty acids. (2 marks) b) Carbohydrates provide 17 kJ/g, while fats provide 37 kJ/g. Why do fats have more energy than carbohydrates? (2 marks) c) For three different polysaccharides, explain how the structure of the molecule allows it to carry out the function (3 marks) d) For the molecule below, label any hydrophobic and hydrophilic regions (2 marks) f) What is the name of the molecule? (1 marks) 3) Complete the simple figure below that shows one end of a replication bubble formed during DNA replication. Make sure you include (and label) the: (6 marks) a) 3’ and 5’ ends of the parental strand b) leading and lagging strands c) RNA primers d) Okazaki fragments e) location and direction of DNA polymerase f) location and direction of helicase g) The Human genome contains 3.2 billion base pairs, but less than 2% of the genetic material encodes protein. How is the process of transcription initiated so that a particular gene is transcribed? (2 marks) h) How is the process of translation terminated? (2 marks) 4a) Draw and label a simple structure of DNA showing the arrangements of the sugar, phosphate and nucleotide base, and the bonds involved in holding the structure together. (4 marks) b) Given the sequence of DNA below (and using the genetic code provided on the front page), what is the sequence of RNA and protein (3 marks) 5’ ATGGGTAGAGCGAACACG 3’ 3’ TACCCATCTCGCTTGTGC 5’ c) Describe the roles undertaken by the 3 different types of RNA found in a cell. (3 marks) 5a) The spike protein on the surface of the COVID-19 virus interacts with the ACE-receptor on the surface of our cells. Describe some of the bonds that might form between the spike protein and the ACE receptor (3 marks) b) The ‘Orthrus’ variant (CH.1.1) of COVID includes a mutation of Leucine (leu) -> Arginine (arg) at amino acid position 452 in the spike protein. Describe the chemical nature of these amino acids (2 marks) b) Predict the mutation in DNA sequence that may have resulted in the Leu -> Arg mutation (2 marks) d) Describe how the arrangement of the genetic code reduces the chances that a nucleotide mutation will affect the protein structure and function (3 marks) 6a) Briefly describe the biochemistry behind the observation that hair straightened using heat doesn't retain its shape as much as getting a perm. (2 marks) b) Briefly describe the biochemistry behind the difference between a RAT and PCR test. (3 marks) c) The enzyme used in PCR reactions is heat stable. Which bonds in an enzyme might otherwise be broken by high temperatures? Which levels of protein structure would this disrupt? (3 marks) d) When cycling, why does Grant rely on fats for energy for long slow rides, while a higher intensity ride relies on carbohydrates? (2 marks) END OF TEST This page has been left blank. You may use this as extra space if needed.