Learning Center
Plans & pricing Sign in
Sign Out

All about blood Heart and blood


									Heart     and   blood

                                      All about blood
                                             Blood is a warm, soupy mixture
                                             of liquid and cells. The cells
                                            carry oxygen and fight germs,
                                           and the liquid carries nutrients to
                                           body cells and takes away waste.
                                                              Main ingredients
                                                              Blood contains three types of cells –
                                                              red blood cells, white blood cells, and
                                                              platelets. They float in a yellowish
                                                              liquid called plasma.

          One drop of
         blood contains
      5 million red blood cells,                            White blood
     half a million platelet cells,                             cells seek
                                           Lots of            out and kill
       7,000 white blood cells,            plasma             germs. They
                                                            also eat up the
          water, sugar, salt,                                 dead cells that
                                            Yellow plasma             they meet.
         hormones, vitamins,                makes up more
                                             than half of
           fat, and protein.                 your blood.

                                                                                          blood red
                                                                                     make          .
                            White blood

                              cells and
                                                                    Red blood

           an expert...
           on fighting germs,
              pages 78-79
          on air and oxygen,
              pages 62-63                                   Red blood cells
                                                            transport oxygen
                                                             from your lungs to
                                                            the rest of your body.
                         How long does a red blood cell live for?
                                                                                          All about blood
                                                     Your blood type
                                                     There are four main types of blood,
                                                     called blood groups. Your blood group
                                                     affects who you can donate blood to.

                                                            People with blood group           People with blood group
                                                       A    A can give blood only to      O   O can donate blood to
                                                            people with A or AB.              almost anyone.
                     Blood bank
            One in ten people                               People with blood group           People with blood group
who go to hospital need extra                               AB can only give blood            B can give blood only to
blood, so hospitals keep a store                      AB    to others with AB blood.      B   people with B or AB.
of blood in a “blood bank”. The
blood is divided into separate
supplies of cells and plasma.                          How much blood?
                                                       The average adult has about
White blood ce                                         10 pints (5.7 litres) of blood,
               lls                                     but a newborn baby
                                                       has only a cupful.

                                                                 The amount of blood
                                                                 in your body grows
                                                                 with you. By age 10
                                                                 you have up to 4 pints

                                                                 (2 litres).
                                     d     t

                       se.       a
Platelets are
cells that become
sticky to make blood
clot and form scabs.

                       By a year old a
                       baby has more
                       1 pint (half a
                       litre) of blood.

                                                     About four months.

To top