The Body in Action

Different Body Systems

Respiratory

Circulatory

Nervous

Skeletal

Digestive

Excretory

Reproductive

Integumentary

Muscular

Endocrine

We will only be focusing on four main systems

Skeletal

Muscular

Circulatory

Respiratory

The Skeletal System

http://www.youtube.com/watch?v=8d-RBe8JBVs

There are 206 bones in the adult human body.

When we are born we have about 300 bones.. How does this work?

Function of the Skeletal System

The skeletal system is the bone structure of the body. Together with muscles it provides core stability and posture. The function of the skeleton is to:

Support body and facilitate movement by providing a point for muscle attachment (lever systems)

Protect vital organs Produce red blood cells Store calcium and phosphate

The skeletal system is made up of two main sections.

1. The ‘axial skeleton’ which includes the skull, thorax and spine which provides support and movement for the upper body.

2. The ‘appendicular skeleton’ includes the bones in our limbs and pelvic area, it allows the body to facilitate large movements i.e. our ability to run, jump and climb etc.

Joints

Types of Joints There are three types of joints:

1. fibrous (as found between the bones of the skull and the pelvis),

2. cartilaginous (as found between the vertebrae and ribs),

3. and synovial (such as the knee and other major joints)

Synovial joints allow the greatest movement (these joints have a synovial membrane and synovial fluid that lubricates the joint and provides nutrients for cartilage). Cartilage is the smooth (avascular) articulating surface of the bone

Joints

There are various types of joints that allow different dimensions of movement

The more space at a joint (between bones) the more movement e.g. knee joint

Joints that allow a large range of movement such as the knee and shoulder rely heavily on connective tissue and are often a potential point of injury

Types of Joints

Ball and socket joint: hip, shoulder

Saddle joint: best example is the thumb

Condyloid joint: wrist-joint, metacarpophalangeal joints, metatarsophalangeal joints

Hinge joint: joint between humerus and ulna, knee and ankle

Pivot joint: Proximal radioulnar joint, Distal radioulnar joint, The Head

Connective tissue

Cartliage

Tendons

Ligaments

Cartliage

Found on ends of bone

Tough, semi transparent, flexible and elastic

Not vasculrised (no blood vessels) or nerves

There are three types of cartilage:

1. Hyaline (joints, trachea & bronchi)

2. Fibrous (vertebrae, articulating cavities)

3. Elastic (lobe of ear, epiglottis and larynx)

Ligaments

The fibrous, slightly stretchy connective tissues that hold one bone to another in the body, forming a joint.

Control range of motion in a joint (eg elbow hyperextending)

Provide stability in a joint

Sprain involves ligaments

Tendons

Connects muscle to bone

Made of similar tissue (collagen) as ligaments but the difference is their connective points.

A strain involves muscle and tendons.

The Muscular System

http://www.youtube.com/watch?v=C6u0u_59UDc

The Muscular System

The body has over six hundred muscles.

Three types of muscles skeletal, smooth and cardiac.

Together with the skeletal system the muscular system allows us to move.

The primary function of the muscular system is to deliver the physical energy for movement.

Physical energy that is derived from oxygen and nutrients supplied via the circulatory, respiratory and digestive systems.

Muscle Movement

Muscles use contraction and relaxation phases to move bones

Muscles always work in pairs (or multiple groups)

One must contract while the other relaxes and visa versa

Agonists and Antagonists

Muscles require an opposite muscle to stretch them back out after contraction. The muscle that does this during a movement is known as the ‘agonist’ muscle

The muscle which lengthens (stretches) is the antagonist and the muscle that is shortened (contracts) is the agonist

Agonist means producing action / antagonist means opposing action

Which is the antagonist muscle in the diagram

below?

Types of Contraction

An eccentric contraction occurs when a muscle is contracting, and an external force is trying to lengthen the muscle.

Isotonic contractions are those which cause the muscle to change length as it contracts and causes movement of a body part.

Isometric: joint angle and muscle length do not change during contraction

Major Skeletal Muscles

The Circulatory Systems

Structure of the circulatory system: The circulatory system is made up of the heart and a

network of blood vessels i.e. arteries, capillaries and veins (see ‘Circulatory System’ handout)

Function of the circulatory system: Regulates blood supply Transports oxygen to cells and removes carbon dioxideContribution to efficient movement:

Having a healthy heart and blood vessels will greatly assist the individuals potential for movement. The uninterrupted supply of oxygen rich blood is crucial to physical performance.

Blood

Plasma: is the liquid part of blood and carries dissolved substances such as glucose and other products. The plasma makes the blood a liquid, the cells in the blood are suspended in the plasma.

Red Blood Cells: contain hemoglobin, a protein that carries oxygen. The role of red cells is to absorb oxygen through the little alveoli in your lungs and deliver it to all the muscles, tissues and organs in your body.

Blood

White Blood Cells: The body uses white blood cells to fight infection, disease and foreign objects in the body.

Platelets: The function of platelets is to help clot the blood in the case of an injury. They quickly create a barrier to prevent too much blood from flowing from a wound.

Blood Vessels

The Circulatory System

Anaerobic Energy System

Is used for exercise that involves short duration.

The system is broken into 2 types

1. The lactate system which relies on the use of glycogen for energy, with lactic acid as the by product.

2. The phosphate energy system relies on the stores of creatine phosphate as the energy source and is used in very fast explosive movements.

Aerobic Energy System

Is used for long duration or endurance exercise that often uses oxygen to break down glucose. This is a system that is used most often.

Most physical activity will begin with this system and call upon the anaerobic system when faster more powerful movement is required.

http://www.youtube.com/watch?v=2hwYD6z_t9o

http://www.youtube.com/watch?v=YnhO9Gfsn8I