Chapter 36: Skeletal, Muscular, and Integumentary Systems Dragonfly Textbook Pages (920-941)

36-1 The Skeletal System Dragonfly Textbook Pages (920-925)

What are some differences between these organisms? Locomotion We have muscles and bones that allow us to move. WHY DO WE NEED TO MOVE?

36-1: The Skeletal System Dragonfly Textbook pages (920-925)

What makes up the skeletal system? Bones Cartilage Ligaments

Bone Fun Facts Human Skeleton accounts for about 20% of a regular sized person’s body weight A baby has about 300 bones; by adulthood there are only about 206 bones Largest part of the skeleton is the femur (located in the upper thigh) Smallest bone in the body is the stapes (part of the inner ear) More than half of your bones are located in your hands, feet, and face A newborn baby’s skeleton is made up mostly of cartilage

2) What are some functions of the skeletal system? Support (framework) Protect internal organs Provides for movement Stores mineral reserves (calcium) Produces blood cells

3) Structure of Bones Bone is composed of living cells and protein fibers that are surrounded by deposits of calcium salts. The calcium salts give bone their hard structure.

4) Cartilage What is it? Strong connective tissue that supports the body and is softer and more flexible than bone Where is it found? places like nose, ear, and joints

5) Joints Examples: What are they? Places where bones meet What do they do? Allow movement Examples: Immovable joints- skull Slightly movable joints- vertebrae Freely movable joints- Ball and Socket (shoulder), Hinge (knee), Pivot (elbow), saddle (hand)

6) Structure of Joints Ligaments: Connective tissue Connects bone to bone Cartilage and bursae (sac of synovial fluid) between bones Reduce friction and act as shock absorbers

36-2 The Muscular System Dragonfly Textbook Pages (926-931)

7) What is the role of our muscular system? Muscles provide the forces that put the body in motion Muscles allow movement by contracting and relaxing. There are 3 types of muscle.

8) Types of Muscle Tissue Skeletal Muscle: Where is it found? Attached to bones Voluntary movements Striations (alternating light/dark bands) Large with many nuclei

8) Types of Muscle Tissue Smooth Muscle: Where is it found? hollow structures- esophagus, stomach and intestines (peristalsis and digestion), blood vessels (control blood flow), eyes (pupil response to light) Involuntary movements No Striations Spindle-shaped with one nucleus

8) Types of Muscle Tissue Cardiac Muscle: Where is it found? The Heart Involuntary movements Striations Small with one or two nuclei

9) Tendons Tough, fibrous connective tissue attaches muscle to bone.

10) Muscle Contraction A muscle contracts when the thin filaments (actin) in the muscle fiber slide over the thick filaments (myosin) The energy for muscle contraction is supplied by ATP!

11) How muscles and bones interact: Skeletal muscles work in opposing pairs Bicep muscle contracts: bends/flexes the elbow Tricep muscle contracts: opens/extends the elbow Controlled movement (ex. Holding a tennis racket or a violin) require contraction by both muscles Muscles provide force and the tendons pull on the bones (like levers)

36-3 The Integumentary System Dragonfly Textbook Pages (933-936)

1) What are the functions of the Integumentary System? A barrier against infection and injury Helps to regulate body temperature Removes wastes from the body Provides protection against ultraviolet radiation from the sun

2) Epidermis Outer layer of skin Made up of two parts: Outer layer of epidermis- dead skin cells Inner layer of epidermis- living cells Undergo rapid mitosis that pushes old cells to the surface Keratin ( protein) producing cells form a flexible, waterproof covering on the surface of the skin Melanocytes- produce Melanin (pigment); the amount and distribution of melanin causes differences in skin color

2) Dermis Middle layer Contains collagen fibers, blood vessels, nerve endings, glands, sense organs, smooth muscles and hair follicles that help the skin perform all of its functions Sweat Glands- produces sweat for temperature regulation and waste removal Sebaceous (oil) glands- produce oil (sebum) keeps epidermis flexible and waterproof

3) Hypodermis (subcutaneous layer) Fat Cells Blood cells

4) Hair and Nails Keratin (which also forms structures like bull horns, reptile scales, bird feathers, and porcupine quills) Hair Covers almost every exposed surface and provides many important functions Produced by hair follicles in the dermis Rapid cell growth at the follicles pushes dead column of keratin- filledcells outward Nails Protect fingers and toes Rapid growth from nail root During cell division, cells produce a plate-like cover that protects fingertips and toes

Chapter 36 Key Ideas Summary 36-1 The Skeletal System The human skeleton supports the body, protects internal organs, provides for movement, stores mineral reserves, and provides a site for blood cell formation Bones are a solid network of living cells and protein fibers that are surrounded by deposits of calcium salts Depending on its type of movement, a joint is classified as immovable, slightly movable, or freely movable 36-2 The Muscular System There are three different types of muscle tissue: skeletal muscle, smooth muscle, and cardiac muscle A muscle fiber contracts when the thin filaments in the muscle fiber slide over the thick filaments. The energy for muscle contraction is supplied by ATP.

Chapter 36 Key Ideas Summary 36-3 The Integumentary System The integumentary system serves as a barrier against infection and injury, helps to regulate body temperature, removes waste products from the body, and provides protection against ultraviolet radiation from the sun.