Mammals

Vertebrates (backbone), have hair, develop specialized teeth backbone

Mammals Have various glands, including mammary glands that produce milk Endothermic (warm-blooded) Can keep a stable temperature by using energy from food Hair/fur and fat also provide insulation

Mammals: Respiration Use lungs to breathe Diaphragm (at bottom of ribs) forces air into and out of lungs In lungs, oxygen enters blood and carbon dioxide exits blood

Mammals: Circulation 4-chambered heart and 2 loops of vessels – keeps oxygen-rich blood completely separate from oxygen- poor blood Blood also removes waste from cells and helps regulate body temperature Blue = oxygen-poor blood Red = oxygen-rich blood

Mammals: Movement Movement- varies with organisms –Walk on 2 or 4 limbs, hop, swing on vines, use flippers

Mammals: Nervous System Receives and interprets information from the environment 5 senses: vision, hearing, smell, taste, and touch Chemical and electrical signals travel to the brain, and the brain directs the action of the body OUCH!

Mammals: Reproduction Reproduce sexually through internal fertilization Mammals are divided into 3 subclasses based on reproductive methods:

Mammals: Reproduction 1.Placental mammals (90%) – give birth to young that have developed inside the mother’s uterus until the body systems are fully developed –Placenta – organ that passes nutrients and oxygen to baby and removes waste from baby through umbilical cord

Placental Mammals

Mammals: Reproduction 2.Marsupials – short period of development inside the mother’s body, then finishes development in a pouch –Ex.: opossum, kangaroo, koala Opossum embryos in a pouch

Mammals: Reproduction 3.Monotremes – lay eggs –Only 3 (2 spiny anteaters and 1 duck-billed platypus)