Dorling Kindersley - Did You Know? Human Body

Established in 1846, the Smithsonian Institutionthe world s largest museum and research complexincludes museums and galleries and the National Zoological Park. The total number of ar tifacts, works of ar t, and specimens in the Smithsonian s collection is estimated at million, the bulk of which is contained in the National Museum of Natural Histor y , which holds more than million specimens and objects. The Smithsonian i s a reno wned r esearch c enter , ded icated t o pu blic e ducation, n ational s erv ice, a nd s cholarship i n th e ar ts, s ciences, a nd h istory . SMITHSONIAN INSTITUTION

Emily Dodd

Body basics What s my body made of? 1011 W hat is the largest or gan? 1213 What s smaller than a cell? 1415 W hy is blood red? 1617 W hat is DNA? 1819 W hy do twins look the same? 2021 Why don t I have my mom s nose? 2223 A re bacteria alive? 2425 W hat are hormones? Piece by piece 2829 W hat are bones made of? 3031 W hat is my biggest muscle? 3233 What s bet ween my brain and skull? 3435 What s inside my heart? 3637 A re my ribs bendy? 3839 H ow does my spine fi t together? 4041 W hy do I need plants to breathe? 4243 H ow does my brain control my emotions? 4445 Why doesn t it hur t when I cut my nails? 4647 W hy are my teeth dif fe rent shapes? 4849 W hy does sugar taste sweet? 5051 W hy does my foot fall asleep? How it works 5455 H ow can I feel light things? 5657 W hy dont I ever for get to bre athe? 5859 W hy can I jump? Author Emily Dodd Consultant Dr . Bipasha Choudhury Smithsonian consultant Darrin Lunde, National Museum of Natural History , Smithsonian Institution Illustrators Dan Crisp, Arran Lewis DK LONDON Editor Kat ie Lawre nce Senior art editor Ann Cannings US Editor Mar garet P arrish US Executive editor Lor i Hand US Senior editor Sha nnon Beatt y Additional editing Man isha M ajithia, O livia S tanford Managing editor Jonathan Melmoth Managing art editor Dia ne Peyton Jones Senior production editor Rob ert Dunn Production contro ller Bar bara Ossows ka Jacket designer Ann Cannings Jacket coordinator Iss y Wa lsh Publishing manager Fra ncesca Y ou ng Creative dire ctor Hel en Seni or Publishing director Sar ah Lar ter DK DELHI Project editor Radhika Haswani Senior art editor Nidhi Mehra Project art editor Bharti K arakoti Managing editor Monica Saig al Managing art editor Romi Chakrabort y Jacket designer Ras hika Kac hroo Jacket editor Radhika Haswani DTP designers Sachin Gup ta, Vija y Kandwal CTS manager Balwant Sing h Production manager Pankaj Shar ma Project pictur e rese archer Sakshi S aluja Delhi creative heads Glenda Fer nandes, Malavika T alukder First Am erican E dition, 2 Publish ed in the United States by D K Publi shing 1450 Bro adway , Suite 801, New Y or k, NY 10018 Copyright 2021 Dorling Kindersley Limited DK, a Division of P enguin Rand om House LLC 21 22 23 2 4 25 10 9 8 7 6 5 4 3 2 1 001321673Mar/2021 All ri ghts re served. Without limiti ng the right s unde r the copyri ght re served above, n o part of t his pub lication m ay be re produced, s tored in or intro duced i nto a re trieval s ystem, o r tran smitted, i n any form, o r by any means (electro nic, mec hanical, p hotocopying, recordi ng, or other wise), w ithout t he pri or wri tten p ermission of the copyright owner . Published i n Gre at Brit ain by Dorling Kinder sley Li mited A catalo g re cord f or this book is avai lable f rom t he Lib rary o f Cong ress. ISBN: 978-0-7 440-2664-1 DK books are availa ble at special discou nts whe n purchased i n bulk for sales pro motions, p remiums, fund-raising, o r educ ational u se. Fo r deta ils, contact : DK Publish ing Spe cial Ma rkets, 1450 Bro adway , Suite 801, New Y or k, NY 10018 SpecialSales@dk.com Printed an d bound in C hina For the curious www.dk.com Smithso nian This book was made with F ore st Stewardship Council cer ti fi ed paperone small step in DKs commitment to a sustainable future. Fo r more information go to www. dk.com/our-gr een-pledge

6061 H ow do bones help me hear? 6263 W hy do my pupils change size? 6465 H ow do I balance? 6667 W hy dont icy drinks make me cold all over? 6869 A m I taller in th e morning? 7071 How do I remember things? 7273 W hat happens to the food I eat? 7475 W hy cant I br eathe underwater? 7677 W hy do I burp? 7879 H ow do babies grow? 8081 D oes my skin last forever? 8283 H ow do I hold my pee? 8485 W hy do I get goose bumps? 8687 W hy do I have eyebrows? 8889 W hy do my ears pop? Healthy habits 9293 W hy do I need food? 9495 W hat happens when I exercise? 9697 W hat is mental health? 9899 W hy do I feel happy and sad? 100101 H ow does soap kill germs? 102103 W hy do people think diff erently? 104105 W hat happens when I age? 106107 W hy do I need water? 108109 W hat is my body clock? 110111 W hat happens when Im scared? Medical marvels 114115 H ow do X-rays work? 116117 W hy do I need vaccinations? 118119 Can magnets show what s inside my body? 120121 H ow do antibiotics kill bacteria? 122123 How do doctors know what s wr ong? 124125 C an my cells change jobs? 126127 H ow does sunscreen work? 128129 C an robots perform sur gery? 130131 H ow can doctors create body parts? 132133 Answers 134137 Quiz your friends! 138139 Glossary 140143 Index C redits and acknowledgments Find out how doctors can see inside your body on page 118. Find out how you breathe on page 56. Q u i c k q u i z ? Te st your knowledge! Look for the Quick quiz box throughout this book to see how much youve learned. Yo ull nd some of the answers on the pages, but you may have to look up or make your best guess for the others. T urn to pages 132133 for the answers.

The human body is made up of cells, which contain unique instructions that make you who you are. Each or gan in your body has an important job to do, and your blood helps to supply them with everything they need to work.

8B ODY BASICS The smallest living building blocks in the body are cells. Ther e are many diff erent types of cell. The same cells join together to build tissue. Groups o f tissues build organs, which work together in or gan systems, su ch as the respiratory system.