ww

w.cardiophile.com

Also known as the circulatory systemThe cardiovascular system is made up of the heart, blood, and blood vessels

www.hcplive.com

Our heart is a muscle that keeps blood flowing through our body, bringing nutrients and oxygen to every cellIt circulates about two gallons of blood throughout the bodyThe system begins in our lungs, where blood picks up oxygen

The heart takes the oxygen-rich blood and pumps it out to all parts of the body

After the cells in the body take in the oxygen from the blood, the deoxygenated blood returns to the heart and is sent to the lungs to get more oxygen

The heart is made up of four chambers separated by one-way gateways called valves

It is divided into a right and left side

www.uptodate.com

The atria have relatively thin walls and function as collection chambers

They only pump blood to the ventricles Left atrium is a hollow chamber that collects

oxygen-rich blood from the pulmonary vein before sending it to the left ventricle.

Right atrium is a hollow chamber that collects blood lacking oxygen from the vena cava before sending it to the right ventricle

The chambers that pump blood out of the heart are called the ventricles.

The ventricles have thicker walls and are much more powerful than the atria

The ventricles are the major pumping chambers for delivering blood to the pulmonary (right ventricle) and systemic (left ventricles) circulations

Left ventricle is a hollow chamber that collects oxygen-rich blood from the left atrium before sending it to the aorta

Right ventricle is a hollow chamber that collects blood lacking oxygen from the right atrium before sending it to the pulmonary artery

The valves each consist of flaps of connective tissue that prevent backflow of blood

Atrioventricular valves and Semilunar valves

Pressure generated by powerful contraction of the ventricles closes the AV valves, keeping blood from flowing back into the atria

Tricuspid valve- valve with three cusps; situated between the right atrium and the right ventricle; allows blood to pass from atrium to ventricle and closes to prevent backflow when the ventricle contracts

Mitral valve- valve with two cusps; situated between the left atrium and the left ventricle

Semilunar valves are located at the two exits of the heart

The blood is pumped out into the arteries through semilunar valves, which are forced open by pressure created by ventricular contraction

The semilunar valves close when the blood starts to flow back toward the heart, so this prevents blood from flowing back into the ventricles

Pulmonary valve- between the right ventricle and the pulmonary artery; prevents blood from flowing from the artery back into the heart

Aortic valve- between the left ventricle and the aorta; prevents blood from flowing from the aorta back into the heart

Aorta- Large artery that distributes oxygen-rich blood from the heart to the rest of the body.

Pulmonary Artery- carries blood lacking oxygen from the hearts right ventricle to the lungs

Pulmonary vein- carries oxygen-rich blood from the lungs into the hearts left atrium

Coronary arteries- vessels that provide the heart muscle with the oxygen-rich blood it needs to keep its tissues healthy. Two main coronary arteries branch off from the aorta, and each of these arteries branches again into yet more arteries that supply oxygenated blood to the different parts of the heat

Vena Cava (superior)-Carries blood lacking oxygen from the head, neck, and arms into the right atrium

Vena Cava (inferior)- carries blood lacking oxygen from legs and other lower parts of the body into the right atrium

When it contracts it pumps blood

When it relaxes its chambers fill with blood

Complete sequence of pumping and filling is called the cardiac cycle

Contraction phase is called systole

Relaxation phase is called diastole

The cardiac output is the blood volume pumped per minute

3 basic blood vessels include capillaries arteries and veins

Transport blood from the arteries to the veins

Oxygen, carbon dioxide, nutrients, and wastes are exchanged through the walls

Capillaries are so small that red blood cells can only travel through them in single file!

Carry blood away from the heart Walls provide strength and elasticity Deliver oxygen-rich blood to the

capillaries We can measure heart rate by

counting the contractions of the artery. That’s how a pulse is taken.

Convey blood back to the heart at low velocity and pressure after the blood has passed through the capillaries

Blood flows through veins as a result of muscle action

Trachea(wind pipe)

Bronchus

Bronchioles

Alveoli

LungIntercostal

muscles

Ribs

Diaphragm

The Respiratory SystemThe Respiratory System

The purpose of the respiratory system is to…

The Respiratory SystemThe Respiratory System

bring the air we breathe into close contact with the blood so that oxygen can be absorbed and carbon dioxide

removed. Basically it consists of:

A pair of lungs connected to the mouth via the trachea and bronchi. The ribs and intercostal

muscles of the chest which protect the lungs, trachea and bronchi.

Air enters the nostrils passes through the nasopharynx, the oral pharynx through the glottis into the trachea into the right and left bronchi, which

branches and rebranches into bronchioles, each of which terminates in a

cluster of Alveoli (Only in the alveoli does actual gas

exchange takes place).

The trachea or windpipe is about 10 cm long and issupported by C-shaped rings of cartilage toprevent the tube from collapsing during breathing.

The tracheasubdivides into the left and right bronchus.The bronchi arealso strengthenedby cartilage.

The two bronchisubdivide to forman extensivenetwork ofBronchioles thatdeliver air to thegas exchangesurfaces – the alveoli.

Air enters the body through the nasal passages and

mouth, and passes via thepharynx and larynx

to the trachea.

Air is delivered tothe alveoli as thetrachea branchesinto bronchi and

bronchioles.

Lungs

main organs of the respiratory system. oxygen taken into the body and carbon

dioxide is breathed out. red blood cells pick up the oxygen in the

lungs and carry it to all the body cells that need it.

Then they pick up the carbon dioxide which is a waste gas product produced by our cells.

The red blood cells transport the carbon dioxide back to the lungs and we breathe it out when we exhale.

The Exchange of Gases within the LungsThe Exchange of Gases within the Lungs

Single alveolus

The 2 bronchi, which lead to each lung divide into many bronchioles. These are less than 1mm in diameter and terminate in grape-like clusters of tiny sacs called alveoli.

Section of lung

Thorax

Gas Exchange

Occurs in the alveloi (air sacs) Capillaries surround the alveoli and allow

gas exchange to occur between the blood and the lungs

Gases diffuse from an area of high concentration to an area of low concentration

Deoxygenated blood - high CO2 low O2

Alveoli - low CO2 high O2

Therefore the CO2 goes from the blood to the lungs and O2 goes from the lungs to the blood

Gas Exchange

Oxygenated blood

Deoxygenated blood

CO2 O2

Alveoli

Deoxygenated blood has

high CO2

low O2

Alveoli have

low CO2

high O2

Oxygenated blood has

low CO2

high O2

Trachea

The trachea is sometimes called the windpipe.

The trachea filters the air we breathe and branches into the bronchi.

Bronchi The bronchi are two air tubes that

branch off of the trachea and carry air directly into the lungs.

Diaphragm

Breathing starts with a dome-shaped muscle at the bottom of the lungs called the diaphragm

When you breathe in, the diaphragm contracts.

When it contracts it flattens out and pulls downward. This movement enlarges the space that the lungs are in. This larger space pulls air into the lungs.

When you breathe out, the diaphragm expands reducing the amount of space for the lungs and forcing air out.

The diaphragm is the main muscle used in breathing.

Negative Pressure Breathing-we pull air instead of pushing it