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

3. Overview of the workings of the Heart
Our heart is a muscle that keeps blood flowing through our body, bringing nutrients and oxygen to every cell
It circulates about two gallons of blood throughout the body
The system begins in our lungs, where blood picks up oxygen

4. 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

5. The Interior of the Heart
The heart is made up of four chambers separated by one-way gateways called valves
It is divided into a right and left side

7. Atria- chambers that receive blood returning from the heart
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

8. Ventricles
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

9. 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

10. The valves
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

11. Atrioventricular valves
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

12. 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

13. 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

14. Exterior of the Heart

15. Heart Exterior
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

16. 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

17. 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

18. Heartbeat 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

19. Blood Vessels
3 basic blood vessels include capillaries arteries and veins

20. Capillaries 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!

21. Arteries 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.

22. Veins
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

24. Sheep Heart Dissection YAY!!!!

25. The Respiratory System
Trachea
(wind pipe)
Ribs
Alveoli
Bronchus
Bronchioles
Lung
Intercostal
muscles
Diaphragm

26. The Respiratory System
The purpose of the respiratory system is to…
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.

27. Pathway 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).

28. The trachea or windpipe is about 10 cm long and is
supported by C-shaped rings of cartilage to
prevent the tube from collapsing during breathing.
Air enters the body through the nasal passages and mouth, and passes via the
pharynx and larynx
to the trachea.
The trachea
subdivides into the left and right bronchus.
The bronchi are
also strengthened
by cartilage.
Air is delivered to
the alveoli as the
trachea branches
into bronchi and
bronchioles.
The two bronchi
subdivide to form
an extensive network of
Bronchioles that deliver air to the gas exchange
surfaces – the alveoli.

30. 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.

31. The Exchange of Gases within the Lungs
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.
Thorax
Section of lung
Single alveolus

32. 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

33. Gas Exchange Deoxygenated blood Oxygenated blood Alveoli CO2 O2
Alveoli have
low CO2
high O2
CO2 O2
Alveoli
Deoxygenated blood
Oxygenated blood
Deoxygenated blood has
high CO2
low O2
Oxygenated blood has
low CO2
high O2

34. Bronchi 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.

35. 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.

36. Negative Pressure Breathing -we pull air instead of pushing it