Question

the blood in some animals are

Answer 1

cold ........or ...pink......hetrogeneteic

Answer 2

Not   all  animals  have  red  coloured   blood.Humans  and  the  majority  of  the  vertebrates have  red  blood.It  is  due  to  the  presence  of  a  protein  called  haemoglobin  which  is  built  up  from  of  'haems'.These  haems  contain  iron  and  gives  blood  its  red  colour    when  it  is  oxygenated  and  when  it  is   deoxygenated   the  colour  of  the  blood  is  deep  red.Some  animlas  have  blue  coloured  blood  like  spiders,crustaceans  etc.Such  animals  contain   haemocyanin  which  contains  copper  in  place  of  iron  and  it    floats  free  in  the  blood.When  deoxygenated  the  blood  is  colourless  but  when  oxygenated  the  blood  gets  a blue  colouration.some  animals  have  violet  blood   due  to  the  presence  of  haemerythrin.When  deoxygenated      haemerythrin  is colourles  but  when  oxygenated  it  gets a  violet-pink  colour.Compared  to  haemoglobin  it's  just  1/4  efficient  in  transporting  oxygen.Such  animals  contain  both  haemoglobin  and  chlorocruorin.  Eg;Some  segmented  worms,leeches etc.
The  blood  is  light  green  when   deoxygenated  and appears light  red when  more  concentrated.