Are you smarter than a 12-year-old? #6 \ stacker news ~science

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402 sats \ 7 comments \ @cryotosensei 9 Nov science

Okay, I realised that my educational system really focuses a lot on mosquitoes. Here’s another question from the 2020 Primary School Leaving Examination:

a) Oil is sprayed on stagnant water as shown.

Explain how this prevents mosquito from breeding. [1]

(b) Malaria is a disease spread by mosquito A. Children infected with malaria are found to be bitten more often by mosquito A.

Joel wanted to find out if children infected with malaria are more attractive to mosquito A due to a certain smell that they produce. He used the set-up shown with 20 of mosquito A in box P.

Joel counted the number of times mosquitoes landed on the shirt for 3 minutes. He repeated the experiment using another shirt worn by an uninfected child in box Q.

(i) State a hypothesis on how the smell on a shirt affects its attractiveness to mosquito A. [1]

(ii) Joel used a white shirt instead of a black shirt for the experiment. Suggest why using a white shirt allows him to obtain more accurate results. [1]

(iii) Joel recorded his results in the table.

Scientists are able to store the smell produced by infected people in a container. Suggest how Joel could use this smell and his results to reduce the number of bites on people. [1]

Question reproduced from Joyous Learning

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15 sats \ 0 replies \ @cryotosensei OP 10 Nov

Answer

a) Oil forms a barrier and prevents air from entering the water. The larvae hence lack the air to stay alive.

b) i) A shirt that has the smell produced by children infected with malaria is more attractive to mosquito A than a shirt that does not have that smell.

ii) A white shirt contrasts with the black mosquitoes more clearly, thus making the mosquitoes more visible. So, people can count the mosquitoes accurately. A black shirt, on the other hand, makes mosquitoes harder to spot.

iii) Mosquito A are attracted to the smell produced by infected people. This smell could be released in an unoccupied part of a house to lure the mosquitoes away from where people actually are. Alternatively, the container which stores the smell produced by infected people can be used to attract and trap mosquitos, which will then lead to fewer bites on people.

48 sats \ 1 reply \ @south_korea_ln 9 Nov

These are some creative questions... it's interesting to learn that it is not based on previous knowledge but on the application of supposedly acquired critical thinking techniques.

I would likely have had a hard time as a 12-year old to answer some of these questions, especially the first one (i hope in the original exam, the quality of the figure was better~~). I did not know that air tubes are formed between the larvae and the surface of the water. Only when knowing that, one can guess that the oil is blocking the flow of air.

5 sats \ 0 replies \ @cryotosensei OP 10 Nov

I think because it’s a one-mark question, children are just expected to reply that oil forms a barrier and prevents air from entering the water, so the mosquitoes lack the air to stay alive.

But since we have a hot housing culture here, the tuition centres and enrichment centres will drill into the kids that larvae have breathing turned, and our well-trained kids will reply as such haha

Are there nationwide exams for sixth graders in South Korea? Will love to look at the questions n compare n contrast syllabus outcomes, esp since I can use ChatGPT to translate questions these days