Chapter 12 section 45 Birds and Mammals Birds

Chapter 12 section 4/5 Birds and Mammals • Birds • The Physics of Bird Flight • What Is a Mammal? • Diversity of Mammals

Characteristics of Birds • Endothermic vertebrate • Feathers • Four-chambered heart ( two atrium and two ventricles. In a four chamber heart oxygen rich blood do not mix with deoxygenated blood • Lays eggs and they have internal fertilization

Four ways birds are adapted for flight • Bones of a bird’s forelimbs form wings • Bones are nearly hollow • Large chest muscles that move the wings • Feathers (Counter Feather gives shape to a bird’s body) • Down feathers (short and fluffy and is used to trap heat

How do birds obtain Food? • After birds eat they have an internal storage tank called the crop which stores food before it enters the stomach. Birds have no teeth but they have a gizzard that squeeze and grind food just like teeth.

Characteristics of Mammals • • • Endothermic vertebrate Four-chambered heart Skin covered with fur or hair Most young are born alive Fed with milk produced in its mother’s body Teeth for chewing their food

How do Mammals obtain oxygen? • All mammals breath with their lungs and they breath in and out using a large muscle called the diaphragm. • The diaphragm is located a the bottom of the ribs.

Explain how Mammals move / and obtain coordination • All vertebrates, mammals have a musculoskeletal system which consists of muscles and bones working together. • When muscle pull on bones it makes the bones move. • The nervous system coordinates the movement of a mammals and the brains of mammals helps them to learn

Three groups of mammals • Monotremes • Marsupials • Placental mammals

Monotremes • There are two species of Monotremes: spiny anteaters and duck-billed platypus. • They are mammals that lay leathery eggs in the pouches of their belly. • After the young hatch they stay in the mother’s pouch for six to eight weeks.

Marsupials • Marsupials are mammals whose young are born alive, but at an early stage of development, and they usually continue to develop in a pouch on their mother’s body. • Short gestation period, length of time between fertilization and birth • Two species of marsupials are: kangaroos and opossums.

Placental Mammals • Placental mammals develop inside its mother’s body until its body systems can function independently. • A few species of placental mammals are: primates, bats, rabbits, elephants, dolphins, otters, squirrels,

What is the function of the Placenta • The Placenta in mammals is an organ in pregnant females mammals that passes materials between the mother and the developing embryo. For example food and oxygen passes form the mother to her young. • Umbilical cord connects the young to the mother’s placenta.

Table comparing mammal groups Characteristic Monotremes Marsupials How Young Begin Life How Young Are Fed Example Milk from pores or slits on mother’s skin Placental Mammals

Writing Assignment • You are a documentary filmmaker preparing to make a short film about spiny anteaters. First, think of a title for the film. Then plan two scenes that you would include in the film and write the narrator’s script. Your scenes should show what the animals look like and what they do.