Body Systems: Skeletal, Muscular, and Digestive

Levels of Organization ~ Organ Systems

Well how many systems do each of us have? Humans (mammals) Circulatory Lymphatic Respiratory Reproductive Muscular Excretory Skeletal Endocrine Integumentary Nervous Digestive

Skeletal System Introductory video clip – Click Here!

Skeletal– Functions (jobs) Gives shape and support Movement Protects internal organs Makes blood cells Stores calcium and other minerals.

Skeletal– Structures (parts) Marrow- the inner part of the bone that makes red blood cells, white blood cells, and platelets Ligaments- tissue that connects one bone to another bone Cartilage- flexible connective tissue that is found on the ends of bones to reduce friction

Joints—Where 2 bones meet Immoveable (fixed)- does not move (skull) Pivot- movement around a point (neck) Ball and Socket- allows 360 degree motion (shoulder and hip) Hinge- allows for open and close motion (knees and elbows Sliding- bones glide past one another (hands and feet) What did one bone say to the other bone? Will you be “jointing” me tonight for dinner? LOL

Do all animals have a skeleton like ours? Nope! Scorpion Sea Urchin Not this guy! His skeleton is an exoskeleton (it is on the outside of his body) Not this one either. His skeleton is an endoskeleton, but much different than ours. Nope! At least he has a backbone like us. Nautilus Not him either! Although he has an endoskeleton, it is still much different than ours. Sting ray

Disorders of the skeletal system Osteoporosis -- weakening of bone due to loss of calcium. Usually in old age.

Muscular System Introductory Video: Click Here

Muscular--Functions Stability and Posture Motion Heat Production Circulation Digestion

Involuntary Muscles (not in our control) Food digestion Circulation

3 Types of Muscles Involuntary Voluntary Involuntary Cardiac Muscle- muscle found in the heart Involuntary Skeletal Muscle- muscle attached to your bones and helps you move Voluntary Smooth Muscle- lines organs such as blood vessels, stomach and digestive tract. Involuntary Voluntary (control) or Involuntary (no control)??

How are our muscles attached to our bones? Tendons attach our muscle to our bones.

The skeletal system and the muscular system work together for movement Make large moveable arm for this slide. Try this out on your own arm. Bend it. Which muscle is “bulging” or shortening? Which one is lengthening? Straighten it. Now, which muscle is “bulging” or shortening? And lenghthening?

In which picture is work being done? Muscles help us do WORK. What is work and when is it really done? Work is done when force is applied over a distance. In which picture is work being done? Force Distance Force Distance

Levers in the Human Body

Structures/Types of Muscle, contd. Skeletal muscles that move your body around come in two varieties: flexors and extensors. Flexors and extensors usually work in pairs, as seen here: i. flexor – bends a joint (biceps) biceps bends the arm triceps straightens it ii. extensor – straightens a joint (triceps)

Disorders Muscular dystrophy is a disease where a person’s muscles weaken after birth and the sick have little control over them. Over time, people with M.D. will often end up in wheelchairs as their muscles fail them. Their minds are completely healthy, though. No cure currently exists for this disease. The MDA (Jerry’s Kids) is the most prominent charity searching for a cure.

Systems working together 1. Skeletal and Circulatory 2. Skeletal and Muscular Bone marrow makes red and white blood cells and platelets. Muscles contract and relax to make the bones move.

Digestive System Introductory Video: Click Here

Digestive– Functions (jobs) Physical breakdown of food Chemical breakdown of food Movement of food through the system Absorption of nutrients Elimination of waste

Digestive– Structures (parts) 1. mouth 1. Digestive– Structures (parts) 2. esophagus 2. 3. 3. stomach 4. 4. small intestine 5. 5. large intestine 6. anus 6.

Disorders of the digestive system Appendicitis – inflammation of the appendix; Doctors typically treat appendicitis with antibiotics and surgery to remove the appendix.