1- sinflar uchun Mindset kitobining "Unit 7- 8" bo’limi yuzasidan summativ baholash
Listening. (Gap fill activity)
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11 grade BSB 1-2
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- Summative Section assessment 4-2 for Grade 11 Student’s name ____________________________Class__________ Reading Complete the diagram
- NO MORE THAN TWO WORDS
Summative Section assessment 4-2 for Grade 11 Student’s name ____________________________Class__________ Reading Complete the diagram Eating up the Titanic In 1985, seventy-three years after it had sunk on its maiden voyage from Southampton to New York, the Titanic was discovered lying 3,800 metres below the surface of the sea. The first images the world saw of the wreck showed the metal hull or body of the ship, draped in what look like strange underwater icicles. These structures are called 'rusticles' from rust (the reddish brown substance that forms on iron when it is in contact with water) and icicle. A decade later, microbial ecologist Roy Cullimore was called on to investigate biological activity on the Titanic after the salvage company recovering objects from the wreck noticed it seemed to be deteriorating. By carefully guiding the robotic claws of the French submarine Nautile, Cullimore was able to collect some rusticles to bring back to his laboratory for analysis. Gathering them was a tricky business - rusticles are brittle and have a tendency to snap in the fast water flow created by the propellers of the submarine. A second expedition brought up more rusticles when a large section of hull was lifted from the sea bed. The largest of these, measuring 45 centimetres long, now hangs on Cullimore's office wall. Each rusticle is made up of communities of bacteria, fungi and other microbes that have joined forces to build a sort of rusting tower block to sustain them and protect them from the outside world. The outer walls have a layered appearance, much like the annular growth rings in trees. Inside, each rusticle seems to contain at least five distinct communities of bacteria, or 'consorms', that live in harmony, with each type of consorm performing a specific task. They are mostly clustered around water channels that run through the structure. There are also fungal growths towards the outside of the structure where the channels meet the surface. Along with the microbes, rusticles contain up to 35 per cent iron compounds in the form of ribbons that permeate the entire structure, in much the same way that nerves or blood vessels do in an animal. Chemically, these compounds are dominated by various ferric oxides, hydroxides and carbonates. Complete the table below. Choose NO MORE THAN TWO WORDS from the text for each answer.
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