Which of these is true?

When we look at how the human body works we are studying its anatomy. Everything you do each day depends on your amazing human body. We are made from cells which group together to form tissues. These tissues then make up different organs. Where would we be without our organs? Could you think without your brain, or breathe without your lungs? Organs work together in systems. Our mouths, stomachs and intestines are just some of the organs in our digestive systems.