Completar Frases BirdsVersión en línea You can review the important information about birds. por Chari P. 1 regulate temperature endothermic Birds are vertebrates . This means they can their own body . 2 flying fly Most birds are adapted to . Some can't , like ostriches . 3 flight resistance less aerodynamic Birds have bodies , which have air . This helps with . 4 bodies scales feathers legs Birds' are covered in , except for the which are covered in . 5 teeth beaks Birds have and don't have . 6 flight hollow lighter They have some bones , which make them and facilitate . 7 limbs wings anterior Their are . 8 sacs air weight muscles lungs They breathe using their . These have to help reduce their and oxygenate the during flight . 9 gizzard chew Birds don't their food . They have a region in their digestive system called the that breaks food up . 10 hearing eyesight Birds have very well - developed and . 11 emit communicate sing Sme birds sounds and " " to with other members of their species . 12 internal oviparous sexually Birds reproduce through fertilisation . All birds are .