Lesson 3 - Mammals

1. Lesson 3 - Mammals Chapter 4 – Birds and Mammals

2. All mammals are endothermic vertebrates that have a four chambered heart and skin covered with fur or hair. • Moat mammals are born alive, and every young mammal is fed with milk produced by organs in it’s mother’s body • These organs are called mammary glands. Characteristics of Mammals

3. Most mammals have teeth that are adapted to chew their food, breaking it into small bits that make digestion easier. • Moist mammals have teeth with four different shapes/ • Canines are pointed teeth that stab food and tear into it. • Premolars and molars have broad, flat upper surfaces for grinding and shredding food. • Incisors are flat-edged teeth used to bit off and cut food. Obtaining Food

4. Mammals breath in and out because of the combined action of rib muscles and a large muscle called the diaphragm. • The diaphragm is located at the bottom of the ribs. • Like birds, mammals have a four chambered heart and two looped circulatory system. Obtaining Oxygen

5. Mammals are endotherms. • They need energy in food to keep a steady internal temperature. • All mammals have fur or hair at some point in their lives that helps them keep their internal temperature stable. • Some mammals also have a layer of fat beneath their skin that helps them live in colder climates. Keeping Conditions Stable

6. Most mammals run or walk on four limbs, but some have specialized ways of movement. Such as hopping, swinging, flying, gliding, and swimming. Movement

7. A mammal’s nervous system coordinates its movements. • The nervous system also enables mammals to learn, remember, and behave in complex ways. • The sense of mammals are highly developed and adapted for the way a species lives. Nervous System

8. There are three main groups of mammals – monotremes, marsupials, and placental mammals. The groups differ in how their young develop. Diversity of Mammals

9. Egg-laying mammals. • There are three species of monotremes – two species of spiny anteaters and the duck-billed platypus. Monotremes

10. Koalas, kangaroos and opossums are some of the better known marsupials. • Their young are born at an early stage of development, and they usually continue to develop in a pouch on the mother’s body. • Marsupials have a very short gestation period. Ex: opossums have a gestation period of 13 days. Marsupials

12. Unlike a monotremeor a marsupial, a placental mammal develops inside its mother’s body until its body systems can function independently. • The name of the group comes from the placenta, which is an organ in pregnant female mammals that passes materials from the mother and the developing embryo. • Placental mammals are classified into two groups on the basis of characteristics such as how they eat and how their bodies move. Placental Mammals

13. Young mammals usually stay with their mother or both parents for an extended period of time. • They learn things that are important to their survival. Caring for Young