There are about 5,000 species of mammals. You and I belong to the class of mammals! Mammals are differentiated from other animals in that they have body hair, three middle ear bones and nourish their young with milk.
Mammals are divided into three subclasses, monotromes, marsupials and placental mammals. Monotromes lay eggs and are primitive mammals. Marsupials are mammals whose young are born very immature. Most female marsupials have pouches, such as the kangaroo. Placental mammals are advanced whose unborn young are nourished through a placenta.
A fossil of a marsupial, Sinodelphys, was found in China. It was found in 125 million-year old early Cretaceous shale. The fossil is nearly complete including tufts of fur and imprints of soft tissues.
Each quiz consists of 10 questions and each question has 4 multiple choice answers. At the top of each quiz you are given a choice of how you want to play it and this affects what happens when you provide an incorrect answer. You can either have the correct answer given immediately, or you can choose to have the questions presented again at the end of the quiz. To print any of the Key Stage 3 quizzes (both questions and answers) click the “Print” link at the bottom of the quiz.
