Crocodiles cannot stick out their tongues.
3. Polar bears are left-handed.
An ostrich's eyes are bigger than its head.
Starfish haven't evolved a brain yet.
6. A cockroach with its head cut off can live for 9 days, and the cause of death after 9 days is starvation.
7. Giraffes can't cough.
8. Owls are the only birds that can distinguish blue.
9. The whale's heartbeat is only 9 times per minute.
10, astronauts can't cry in space because tears can't flow without gravity.
1 1. Elephants will still stand after death.
12. Some insects can live without their heads 1 year.
13, the wing length of a Boeing 747 is just the distance of the Wright brothers' first flight.
14, when using air conditioning in summer, the temperature should be set at 26-28 degrees.
15. Cooking oil fume in the dining room kitchen will cause pollution and endanger health, so it is necessary to install an oil fume purification device.
16. Eating iodized salt can meet the iodine intake of human body. The salt people usually use is iodized salt. Because of the volatility of iodine, we should seal the iodized salt.
17, geothermal energy, wind energy, solar energy and other energy sources that can avoid air pollution after use are called clean energy.
18. Eat less salt. The World Health Organization suggested that the appropriate daily intake of salt was 6 grams, while the actual daily intake per capita in China was more than 13 grams, which exceeded the standard amount 1 times.
19, the higher the altitude above the ground, the less atmospheric molecules and the less light scattered by air molecules, so the sky becomes dark.
20. Wild animals contain a large number of parasites, and people can easily induce some parasitic diseases such as cerebral cysticercosis, paragonimiasis and intestinal parasitic diseases after eating them.