Читать книгу The House We Live In; or, The Making of the Body онлайн

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Percy: And do the cells last as long as we live, mother?

CELLS

Mother: No, they keep changing all the time. When we walk, run, talk, think, or do anything, some of these cells die, and others take their places. The new ones are just like the old; for if they were not, our appearance would so change that our best friends would not know us. While boys and girls are growing, they are putting many new cells into the house they live in. This is the reason auntie said the other day that she hardly knew you when she had not seen you for a year.

Amy: What are the cells made of, mother?

Mother: They are made of the food we eat. This shows we should be careful to put the very best things we can get into our body-building—I mean such as the body can use, for what we like best is not always what is needed to build up and strengthen us. When you get hungry, that is the call of the body for food to make more cells, just as the mason calls, “More mortar,” or, “More brick,” so he can build his wall higher and stronger. If his mortar has but little lime, or is badly mixed, or he has only broken, badly-shaped brick, the wall will not be strong or beautiful. So if we give the body wrong kinds of food, it can not build such a house as you and I wish to live in.