Chapter 13 Bones and Muscles

Big Idea How do the physical principles of forces and machines relate to the functions of your muscles and skeleton?

Chapter 13, Section 1: Organ Systems and Homeostasis Levels of organization in the human body Cells Tissues Organs Organ systems Organism Table Talk: from our study of cells, are you able to name some specific tissues, organs and organ systems?

CELLS REVIEW: Cells grow, reproduce & undergo cellular respiration Together, many cells form tissues

TISSUE A group of specialized cells Table Talk: Can you name some specialized tissues (and their function) in your body? Muscle tissue Nervous tissue (heart) Connective tissue (cartilage) Epithelial tissue (skin)

Types of Tissues Muscle – Can contract, or shorten – Makes your body move Nervous – Carries electrical messages between the brain and body parts – Directs & controls Connective – Provides support for your body – Bones, fat, cartilage Epithelial – Surfaces of your body, inside & out – Skin, digestive lining, etc. SUMMARIZE, with your shoulder partner, the jobs of these tissues. CHECK WHAT YOU KNOW!

Organs Organ System Tissues make up organs Heart, liver, lungs, brain, etc. Can you name some others? A group of organs that work together to perform a major function Can you think of any? Some organ systems: skeletal, muscular, circulatory, respiratory, digestive, excretory, reproductive, immune, nervous

Homeostasis When all the systems of the body work together to keep its internal environment stable, in spite of changes in the external environment Table talk: discuss with your table what you think this means.

Sometimes homeostasis is interrupted Usually due to stress (threatening, challenging, or disturbing events) What are symptoms of stress?: – Rapid heart rate – Increased breathing – Flood of adrenaline (energy burst) Table Talk: What do you suppose restores homeostasis? REST!! See BrainPops “Human Body: All Systems Go” and “Homeostasis” End