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What Mitosis Has to Do with Families

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On a warm summer night, Lily’s parents turned off the television and invited her to look at some old family

photos. The three of them began by flipping through a large album of old printed photographs, each one taken

with a film camera during the 1980s. The man and woman in the pictures were much younger than the

mother and father sitting beside their daughter, turning each page in the album.

Still, Lily could recognize her parents easily. Through the faded colors and strange‐looking clothes, the bright

shock of red hair on her mom’s head stood out in almost every shot. Although her father’s hair changed

quickly in the pictures, from a sandy gold to a salt‐and‐pepper grey, his blue eyes looked almost as sharp at

the age of 50 as they did when he was 20. Lily wondered why her hair wasn’t red like her mother’s, and why

her eyes weren’t blue, like her father’s.

A long series of events has allowed Kate, Tom, and their 10‐year‐old daughter Lily to grow from newborn

babies into the family they are today. Everything started, however, with a fertilized egg in the mother’s womb.

Narrative Non-fiction: What Mitosis has to do with Families

Lily, along with her parents and every other human being on the planet, grew from that egg into the girl she is

today. She will keep growing until she is an adult, and maybe even a mother who has a daughter of her own.

She grows because she is what scientists call a multicellular organism—a living thing that is made from many

cells.

Humans aren’t the only organisms that depend on mitosis for growth. Lily’s dog, Lion, was once a puppy that

could fit in her arms. After just a few years, he’s grown into a full‐sized German Shepard, almost big enough to

carry Lily on his back. Lion’s feet and fur have grown in exactly the same way as Lily’s feet and hair—though

Lion, with his sturdy paws, has never had a particular need for a pair of new sneakers.

The same goes for the trees in their backyard, where Lily and Lion play fetch and roll in the grass on hot

summer days.

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