BIOLOGY 2019 Unit 3 Key Topic Test 5 – Photosynthesis QUESTION BOOK

Plants, most algae, some protists and cyanobacteria perform photosynthesis. These organisms are called photoautotrophs. The purpose of photosynthesis in photoautotrophs is to A. create ATP for energy B. generate oxyge ...

Plants, most algae, some protists and cyanobacteria perform photosynthesis. These organisms are called photoautotrophs. The purpose of photosynthesis in photoautotrophs is to A. create ATP for energy B. generate oxygen for cellular respiration C. make sugars from oxygen and water D. convert light energy into chemical energy Question 2 Green photosynthetic plants contain organelles where photosynthesis occurs. These organelles are called A. chlorophyll B. chromoplast C. chloroplasts D. leucoplast Question 3 The site of photosynthesis in plants is a type of organelle known as a plastid which is characterized by its two membranes and high concentration of chlorophyll. The part of the plastid that contains chlorophyll is called the A. thylakoid space B. thylakoid membrane C. stroma D. lumen Question 4 Photosynthesis consists of two stages, both of which occur in the plastids of plants. The light independent stage occurs in which area of the plastid? A. Thylakoid space B. Thylakoid membrane C. Stroma D. Lumen 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 4 of 9 Question 5 A feature of chloroplasts is that they contain their own DNA called a plastome. This single large circular DNA is essential for the functioning of the chloroplast because it has the instructions for A. building enzymes involved in the Krebs cycle B. synthesising cofactors for chlorophyll C. building proteins involved in light independent reactions D. building water splitting proteins for the Calvin cycle Question 6 Cyanobacteria are considered the ancestors of chloroplasts. The theory which suggests that free living cyanobacteria entered an early eukaryotic cell is called A. endosymbiosis B. ectosymbiosis C. cyanobiont D. binary fission Question 7 Chloroplasts are believed to have joined eukaryotic cells after mitochondria as A. cyanobacteria are still present today B. all eukaryotes contain mitochondria but not all have chloroplasts C. some prokaryotes contain chloroplasts but not mitochondria D. chloroplasts have their own DNA Question 8 The two stages of photosynthesis occur in different parts of the chloroplast but are connected by inputs and outputs that are sometimes carried by coenzymes. Loaded coenzymes that are involved in moving between the light dependent and light independent reactions are A. ATP and ADP + Pi B. ATP and NADPH C. ATP and NADH D. NADH and NADPH 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 5 of 9 Question 9 Water is an input into the light dependent stage where the energy from sunlight is used to break the bonds between elements generating outputs which are carried to the light independent stage. These outputs include A. water, oxygen, ATP and NADPH B. oxygen, ATP and NADPH C. ATP and NADPH D. oxygen, hydrogen and electrons Question 10 Inputs to the light independent reaction include A. carbon dioxide and water B. pyruvate and carbon dioxide C. NADH and Carbon dioxide D. carbon dioxide and ATP Question 11 A major part of the light independent reaction in C3 plants is the Calvin cycle. The Calvin cycle or C3 cycle fixes carbon dioxide from the atmosphere in three stages using the inputs from carrier molecules from the light dependent stage. Enzymes are used to catalyse the three stages including the key enzyme A. RuBisCo B. ATP synthase C. carbon monoxide dehydrogenase D. chlorophyll Question 12 The rate of photosynthesis in plants is affected by a range of factors linked to the inputs of each of the stages. As light intensity increases the rate of photosynthesis increases proportionally in a straight-line relationship until the rate plateaus due to other limiting factors. These limiting factors may be A. carbon dioxide concentration and oxygen levels B. temperature and chlorophyll C pigment C. light intensity and water levels D. temperature and carbon dioxide concentration 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 6 of 9 Question 13 Photosynthesis and cellular respiration are linked because A. the outputs of one become the inputs of the other B. plants produce glucose that animals can use for oxygen production C. animals produce carbon dioxide that plants can use in the light dependent stage D. plants use the outputs of animal cellular respiration to split water Question 14 The optimal temperature for photosynthesis is 250C. As carbon dioxide levels increase in the atmosphere due to the burning of fossil fuels these levels promote an increase in temperature across the world. While an increase in carbon dioxide would promote an increase in photosynthetic rates, what would an increase in temperature above optimal temperatures do? A. Decrease humidity supplying less water for the light dependent reaction B. Decrease the photosynthetic rate due to enzymes in the Calvin cycle denaturing C. Increase the photosynthetic rate due to more oxygen being released for respiration D. Increase the photosynthetic rate due to higher light intensity Question 15 Which graph shows the effect of temperature on the rate of photosynthesis? A. Graph A B. Graph B C. Graph C D. Graph D 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 7 of 9 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 Photosynthetic organisms produce sugars. The major organelle involved in the production of sugars in plants is the chloroplast - a double membraned plastid which has specialised structures that assist in the photosynthetic process. a. Label the diagram below Source modified from: https://www.biologycorner.com b. With reference to the diagram above and/or your own knowledge, identify which area(s) are involved in the light independent reaction? _____________________________________________________________________ c. Structure D and E are involved producing essential materials for the efficient functioning of photosynthesis. What type of functional proteins are produced? Give an example of a functional protein used in photosynthesis? _____________________________________________________________________ _____________________________________________________________________ A B C D E 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 8 of 9 d. The structure of chloroplasts reveals evidence of a cyanobacteria ancestor. While the double membrane was once thought to provide evidence of the engulfment of a cyanobacteria by a eukaryotic cell, further study has determined that the membranes are more like the ancestral cyanobacteria. What evidence is there that chloroplasts arose from cyanobacteria? _____________________________________________________________________ _____________________________________________________________________ 5 + 1 + 2 + 3 = 11 marks Question 2 Photosynthesis occurs in two stages that both occur in the chloroplast in plants. Each of the stages of photosynthesis occur in separate parts of the chloroplast and have their own inputs and outputs a. Complete the table below to show the inputs and outputs for each stage: Stages Location Inputs Outputs Light independent Light dependent 14 marks 2019 BIOLOGY KEY TOPIC TEST  TSSM 2019 Page 9 of 9 Question 3 Factors that affect the rate of photosynthesis include light intensity and wavelength, temperature and carbon dioxide. Changes in these factors affect how efficiently a plant can produce sugars through photosynthesis. One of these factors is influenced by the process of cellular respiration. The relationship between the rate of carbon dioxide produced by respiration and the amount used by photosynthesis can be graphed. Modified from source: https://www.chegg.com a. Referring to the above graph indicate the length of time the organism is undergoing photosynthesis? _____________________________________________________________________ b. With reference to the graph explain what a compensation point is and why there are 2 on this graph _______________________________