耳あかが「カサカサ」か「ベタベタ」かは、遺伝子のたった1文字の違いで決まっていた

Q1. What is the passage mainly about?

1. AHow to clean your ears
2. BWhy people use soap
3. CA gene that decides earwax type and body smell
4. DThe history of Japan

耳あかのタイプと体のにおいを決める遺伝子がテーマなので C。

Q2. What kind of earwax do most Japanese people have?

1. AWet earwax
2. BDry earwax
3. CNo earwax
4. DBoth types equally

Most Japanese people have dry earwax とあるので B。

Q3. In this passage, "roots" means ...

1. Aparts of a plant under the ground
2. Bteeth
3. Chair on the head
4. Dthe place where your family originally came from

with European or African roots は「ヨーロッパやアフリカにルーツ（家系の出身地）を持つ」という意味なので D。

Q1. Who inherits dry earwax, according to the passage?

1. APeople with one copy of the A version
2. BPeople with no copies of the A version
3. CPeople who inherit two copies of the A version
4. DOnly people born in Nagasaki

People who inherit two copies of the A version have dry earwax. とあるので C。

Q2. What does the protein made by ABCC11 do?

1. AIt pumps substances out of cells.
2. BIt kills bacteria in the ear.
3. CIt makes hair grow.
4. DIt changes the color of skin.

This gene makes a protein that pumps substances out of cells とあるので A。

Q3. Why do people with dry earwax tend to have less underarm odor?

1. ABecause they wash more often
2. BBecause they live in cold places
3. CBecause they use more deodorant
4. DBecause they release fewer substances that bacteria turn into odor

同じ遺伝子が細菌によってにおいに変わる物質を制御しており、A型ではその分泌が少ないため。正解は D。

Q1. Which statement best summarizes the passage?

1. AEarwax type is determined by diet.
2. BWet earwax is a sign of poor hygiene.
3. CDeodorant use is fully controlled by genes.
4. DOne DNA variant in ABCC11 affects earwax, underarm odor and possibly adaptation.

ABCC11の1つの変異が耳あか・わきのにおいに関わり、自然選択を受けた可能性もあるという内容なので D。

Q2. What did the 2010 study find?

1. AABCC11 works in apocrine sweat glands, and AA individuals barely secrete odor precursors.
2. BEarwax type depends on climate only.
3. CThe A allele increases body odor.
4. DABCC11 is found only in the ear.

the gene also works in the apocrine sweat glands of the armpit, and that people with two A alleles barely secrete the precursors とあるので A。

Q3. What does the author suggest by mentioning that low-odor people still used deodorant?

1. ADeodorant changes a person's genes.
2. BGenes alone do not determine people's habits.
3. CThe cohort study was unreliable.
4. DLow-odor people actually smell strongly.

most low-odor people used deodorant anyway の直後に So genes did not dictate the habit. とあるので B。