Bones, Muscles, Blood, and Lungs

In this lesson, you will Learn About…

How the skeletal and muscular systems

support and move your body.

How the circulatory system moves blood

throughout your body.

How the respiratory system works to help

you breathe.

Bones, Muscles, Blood, and Lungs

The Vocabulary terms in this lesson are:

Skeletal system

Joints

Muscular system

Circulatory system

Heart

Blood pressure

Respiratory system

Lungs

Diaphragm

The Skeletal System

The skeletal system is a framework of bones and the tissues that connect the bones.

Bones

Your bones support your body and protect its soft parts from injury.

With the help of your muscles, bones also allow you to stand and move.

Bones are hard on the outside and have a spongy tissue inside that produces blood cells.

Joints

There are three different types of joints:

Pivot joint - consists of the end of one bone rotating inside a ring formed by another bone.

Hinge joint - moves in only one direction, much like a door hinge.

Ball-and-socket joint - consists of a round end of one bone moving inside the cup-shaped socket of another bone.

The Skeletal System

Pivot joint (neck)

Hinge joint (elbow)

Ball-and-socket joint (hip)

Skull

Clavicle (collar bone)

Rib cage

Humerus

Radius

Ulna

Vertebrae (Spine)

Pelvis

Femur

Patella (knee cap)

TibiaFibula

The Muscular System

The muscular system is made up of muscles that move bones, pump blood, and move food through the stomach and intestines, among other jobs.

There are three types of muscles:

Skeletal – found in places such as the arms and back; called voluntary muscles because a person can control them.

Cardiac – found only in the heart; called involuntary muscles because they work without a person’s controlling them.

Smooth – found in places such as those in the stomach; called involuntary muscles because they work without a person’s controlling them.

The Muscular System (cont’d.)

PectoralTriceps

Abdominal

QuadricepsSartorius

Biceps

Deltoid

Stomach(smooth muscle)

Heart(cardiac muscle)

Biceps(Skeletal muscle)

The Circulatory System

The circulatory system helps blood move to and from the tissues of the body to:

Deliver oxygen, food, and other material to cells.

Remove wastes from cells.

The Circulatory System (cont’d.)

A

B

C

Pulmonary VeinPulmonary

artery

Lungs

Heart

Arteries

Capillaries

Veins

The Work of the Heart

The heart pushes blood through the blood vessels, the tubes that carry blood throughout the body.

There are three types of blood vessels:

Arteries - carry blood away from the heart Veins - return blood to the heart Capillaries – tiny blood vessels that connect

arteries and veins and provide blood directly to cells.

Blood Pressure

Blood pressure is greatest when the heart contracts to push out blood.

It is lowest between heartbeats, when the heart relaxes.

Parts of the Blood

Blood contains both liquid parts (plasma) and solid parts (cells).

Plasma – transports blood cells and dissolved food.

Red blood cells – carry oxygen to all other cells of the body and carry away some waste products.

White blood cells – help destroy disease-causing germs that enter the body.

Platelets – help the blood to clot.

Blood Types

Blood is classified by the type of red blood cells a person has.

There are four main blood types: A, B, AB, and O.

Mixing of some blood types can have serious side effects when a person receives blood from someone else.

Blood Types (cont’d.)

Blood may contain an Rh factor. It is either Rh-positive or Rh-negative.

An Rh-positive person can receive blood from both an Rh-positive and an Rh-negative person.

An Rh-negative person can receive blood only from an Rh-negative person.

The Respiratory System

The respiratory system is divided into:

Upper Respiratory System – Air comes into the body through the nose or mouth; it then enters the trachea, or windpipe.

Lower Respiratory System – The trachea divides into two branches called bronchi that carry air into the lungs. The bronchi divide into smaller and smaller branches and end in structures called alveoli.

The Respiratory System

Nose and mouth

Trachea

Alveoli

Lungs

Bronchi

Upper Respiratory System

Lower Respiratory System

How You Breathe

Breathing begins with the diaphragm.

When you breathe in, the diaphragm contracts. When you breathe out, the diaphragm expands.

Squeezing the bottle forces air out. This is similar to what happens when you breathe out. A relaxed diaphragm moves upward and squeezes air out of your lungs.

Letting the bottle return to its original shape lets air rush in. this is similar to what happens when you breathe in. A tightened diaphragm moves downward and allows the lungs to fill with air.

Reviewing Terms and Facts

1. _________ are places where one bone meets another. The three major joint types are _________, ________, and _____________.

Joints

pivot hingeball-and-socket

Reviewing Terms and Facts

2. Which body system carries food and oxygen to cells?

The circulatory system carries food and oxygen to cells and removes wastes from cells.

Reviewing Terms and Facts

3. What role does the skeletal system play in your body?

The skeletal system is a framework of bones and tissues that connect the bones. The bones support the body and protect its soft parts from injury. With the help of muscles, they also allow the body to stand and move.

Vocabulary Review

The skeletal system is a framework of bones and the tissues that connect the bones.

Vocabulary Review

Joints are places where one bone meets another.

Vocabulary Review

The muscular system is made up of all the muscles in your body.

Vocabulary Review

The circulatory system enables the body to transport, or move, materials from one place to another.

Vocabulary Review

The heart is the muscle that acts as the pump for the circulatory system.

Vocabulary Review

Blood pressure is the force of blood pushing against the walls of the blood vessels.

Vocabulary Review

The respiratory system enables you to breathe.

Vocabulary Review

The lungs are the main organs of the respiratory system.

Vocabulary Review

The diaphragm is a large muscle at the bottom of the chest.