DO NOT OPEN THE EXAM UNTIL YOU ARE TOLD TO BEGIN SCIENCE 1206 MIDTERM EXAMINATION NAME: PART 1 - MULTIPLE CHOICE PART 2 - EXTENDED RESPONSE MARK
Part A: Multiple Choice - Place the letter corresponding with the best possible answer in the space on the answer sheet. (Value: 30 marks) (1) Which Canadian biome is characterized by deep and fertile soil, 25-75 cm of rainfall annually and indicator animals such as bison, voles, mice, snakes and hawks? (a) tundra (b) taiga (c) grassland (d) temperate deciduous forest (2) What factor is biotic? (a) amount of light on a forest floor (b) dead moose on a bog (c) temperature in a stream (d) ultra-violet light (3) Which of the following would be considered a density-independent factor? (a) disease (b) availability of food (c) forest fire (d) number of predators (4) Moose and black duck feed on the same young shoots of aquatic plants. This is an example of (a) interspecific competition (b) aggression (c) mutualism (d) intraspecific competition (5) Which of the following describes the aquatic eutrophication of a lake due to fertilizer run off into streams? (a) decreased production of algae, dissolved oxygen levels reduced (b) increased production of algae, dissolved oxygen levels reduced (c) decreased production of algae, dissolved oxygen levels increased (d) increased production of algae, dissolved oxygen levels increased (6) In an area there are 3000 of species A, 150 of Species B, 15 of Species C and 2 of Species D. Which species would you consider most likely to be a tertiary consumer? (a) Species A (b) Species B (c) Species C (d) Species D (7) Secondary succession is faster than primary succession because secondary succession does NOT (a) begin with soil formation (b) begin with lichen growth (c) end with a climax community (d) end with a dominant species (8) If 12 500 joules (J) of solar energy reaches a producer, how much of this energy will reach a second order consumer? (a) 1.25 J (b) 12.5 J (c) 125 J (d) 1250 J (9) Which is true concerning the flow of energy and matter in an ecosystem? (a) both energy and matter are recycled (b) neither energy nor matter are recycled (c) only energy is recycled, matter is lost (d) only matter is recycled, energy is lost
(10) This model expresses all the possible feeding relationships and is more likely to exist within an ecosystem. (a) food web (b) food chain (c) food diagram (d) pyramid of energy (11) What at risk classification is given to a species that no longer exists in one part of Canada but can be found in others? (a) endangered (b) vulnerable (c) threatened (d) extirpated (12) A group of organisms of the same species living in a specific area is called a(an) (a) ecosystem (b) community (c) population (d) niche (13) In which of the following would you find a second order consumer? (a) first trophic level (b) second trophic level (c) third trophic level (d) fourth trophic level (14) Consider this possible situation. A species of European squirrel is introduced to a small, wooded island where a local squirrel population has been established for for many years. After 10 years, only the European species remains. What is the most likely reason for this? (a) competition over the same niche has lead to the extinction of the local population (b) the European squirrel preyed on the local species (c) the European squirrel produced more offspring than the local squirrel (d) the European squirrel was faster and could escape predators (15) Which of the following represent concerns surrounding the use of modern chemical pesticides? (a) fat soluble, rapid breakdown in ecosystem (b) water soluble, do not bioaccumulate (c) block electrical messages in nerves, require reapplication (d) fat soluble, high cost (16) The component of soil which contains small particles of rock mixed with decaying plant and animal material. (a) topsoil (b) subsoil (c) bedrock (d) litter (17) Which type of bacteria convert nitrogen in the atmosphere to nitrogen in the soil? (a) nitrogen fixing bacteria (b) denitrifying bacteria (c) parasitic bacteria (d) ammonia bacteria (18) This principle involves meeting the needs of the present generation without compromising the ability of future generations to meet their needs. It also includes the concept of maintenance of biodiversity. (a) environmental protection (b) sustainability (c) preservation
(d) paradigm shift (19) Which of Canada s terrestrial biomes contains the LEAST biodiversity? (a) tundra (b) taiga (c) grassland (d) temperate deciduous forest (20) Which ecosystem would show the LEAST stability? (a) an ecosystem represented by a food chain (b) an ecosystem with a large biodiversity (c) an ecosystem in Canada s arctic (d) an ecosystem within the grassland (21) When a molecule of CCl 4 is formed, electrons are (a) shared and covalent bonds are formed (b) shared and ionic bonds are formed (c) transferred and covalent bonds are formed (d) transferred and ionic bonds are formed (22) Which of the following statements is CORRECT concerning ions? (a) cations form when an atom gains electrons (b) cations form when an atom loses electrons (c) anions form when an atom gains protons (d) anions form when an atom loses protons (23) How many electrons surrounds the nucleus of the chloride ion? (a) 1 (b) 16 (c) 17 (d) 18 (24) Which of the following elements exists as a diatomic? (a) neon (b) lithium (c) nitrogen (d) sulfur (25) How many lone pairs are in the Lewis diagram for nitrogen? (a) 1 (b) 2 (c) 3 (d) 6 (26) Which of the following is a physical change? (a) changing solid metal to liquid metal (b) burning coal (c) two solutions when mixed form a precipitate (d) hydrogen gas bubbles are produced when zinc is placed in concentrated acid (27) Which element gains three electrons to achieve a stable octet of valence electrons? (a) nitrogen (b) silicon (c) oxygen (d) sulfur (28) Which of the following is NOT a molecular element? (a) lithium (b) nitrogen (c) oxygen (d) sulphur
(29) Which of the following is the WHMIS symbol for materials that are poisonous and infectious materials causing other toxic effects? (a) (b) (c) (d) (30) Material Safety Data Sheets are intended for use by all of the following EXCEPT. (a) consumers in the home who are concerned with storing cleaners (b) employees who may be occupationally exposed to a hazard at work (c) employees who need to know the proper handling methods for storage (d) emergency responders such as firefighters Answer Key Part A - Multiple Choice
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) Part B: Short Answer Answer all of the following questions on this paper. Show all workings. (Value: 35 marks) (1) Describe the tundra biome in terms of the following abiotic factors; radiant energy supply, precipitation, soil (include TWO points), indicator animals (include TWO) and indicator plants (include TWO). Are two types of tundra possible? Explain! [5]
(2) Briefly describe the nitrogen biogeochemical cycle. A diagram may be helpful in your explanation. Include a discussion of ONE human impact that can disrupt this cycle and the environment. [5] (3) Briefly describe THREE categories of pesticides. Discuss the concern of bioaccumulation (bioamplification) and ONE OTHER concern once they are released into the environment [5] (4) What is a covalent bond? Methane (CH 4 ) is a molecular compound that achieves its stability through covalent bonding. Draw Bohr models for the atoms that make up methane. Draw Lewis diagrams for the same atoms. Explain using these models and the Octet rule how this stability is achieved. [5]
(5) What is an ionic bond? Magnesium oxide (MgO) is an ionic compound that achieves stability through ionic bonding. Draw Bohr models for the magnesium and oxygen atoms. Draw Bohr models for the magnesium and oxide ions. Explain using these models and the Octet rule how this stability is achieved. [5] (6) Complete the following table regarding nomenclature of molecular compounds, ionic compounds and acids. [10] Name of Compound copper(i) sulfate Correct Formula
calcium bicarbonate barium thiosulfate dinitrogen tetraoxide calcium phosphate sulfur ammonia titanium (III) nitride sulfur pentachloride plumbic oxide PdO 2 CuSO 4-5H 2 0 CS 2 H 2 O 2 NH 4 NO 3 V 2 O 5 K 2 Cr 2 O 7 CCl 4 N 3 O 7 Al 2 O 3