1. Chapter 33 Circulatory and Respiratory Systems
33.1: The Circulatory System
33.2: Blood and the Lymphatic System
33.3: The Respiratory System

2. The circulatory system moves blood to all parts of the body.
veins
arteries
The system includes the heart, arteries, veins, and capillaries.
heart pumps blood throughout body
arteries move blood away from heart
veins move blood back to heart
capillaries get blood to and from cells

3. Circulatory System
There are three major functions of the circulatory system
The heart is a muscular pump that moves the blood through two pathways
transporting blood, gases, nutrients
collecting waste materials
maintaining body temperature

4. The tissues and structures of the heart make it an efficient pump.
Cardiac muscle tissue works continuously without tiring.
NORMAL HUMAN HEART

5. The heart has four chambers: two atria, two ventricles.
Valves in each chamber prevent backflow of blood.
aortic valve
left atrium
mitral valve
left ventricle
septum
pulmonary valve
right atrium
tricuspid
right ventricle
Muscles squeeze the chambers in a powerful pumping action.

6. The heartbeat consists of two contractions
SA node, or pacemaker, stimulates atria to contract
AV node stimulates ventricles to contract
SA node
VA node

7. Blood flows through the heart in a specific pathway.
oxygen-poor blood enters right atrium, then right ventricle
right ventricle pumps blood to lungs
oxygen-rich blood from lungs enters left atrium, then left ventricle
left ventricle pumps blood to body

8. The heart pumps blood through two main pathways.
Pulmonary circulation occurs between the heart and the lungs.
oxygen-poor blood enters lungs
excess carbon dioxide and water expelled
blood picks up oxygen
oxygen-rich blood returns to heart

9. Systemic circulation occurs between the heart and the rest of the body.
oxygen-rich blood goes to organs, extremities
oxygen-poor blood returns to heart
The two pathways help maintain a stable body temperature.

10. Arteries, veins, and capillaries transport blood to all parts of the body.
The circulatory system transports materials throughout the body
Arteries carry blood away from the heart.
blood under great pressure
thicker, more muscular walls
ARTERY
VEIN
CAPILLARIES
arteriole
venule
endothelium
connective tissue
smooth muscle
valve

11. Veins carry blood back to the heart.
blood under less pressure
thinner walls, larger diameter
valves prevent backflow
ARTERY
VEIN
CAPILLARIES
arteriole
venule
endothelium
connective tissue
smooth muscle
valve

12. Capillaries move blood between veins, arteries, and cells.
ARTERY
VEIN
CAPILLARIES
arteriole
endothelium
connective tissue
smooth muscle
venule
valve

13. Blood pressure is a measure of the force of blood pushing against artery walls.
systolic pressure: left ventricle contracts
diastolic pressure: left ventricle relaxes
High blood pressure can precede a heart attack or stroke.

14. Lifestyle plays a key role in circulatory diseases.
Some choices lead to an increased risk of circulatory diseases.
smoking
long-term stress
excessive weight
lack of exercise
diet low in fruits and vegetables, high in saturated fats

15. Circulatory diseases affect mainly the heart and the arteries.
artery walls become thick and inflexible
plaque blocks blood flow in arteries

16. Blood Blood is a complex tissue that transports materials
Blood is composed mainly of cells, cell fragments, and plasma
Whole blood is made up of different materials.
plasma
red blood cells
white blood cells
platelets
red blood cells,
white blood cells,
and platelets
plasma

17. Blood—quick summary:
Plasma = 90 percent water and helps with blood clotting
Red blood cells = transport oxygen using hemoglobin
White blood cells = guard against infection
Platelets = fragments of cells used for blood clotting

18. Plasma About 55 percent of total blood volume is plasma
Plasma is about 90 percent water, which helps to control body temperature
Fibrinogen = special plasma protein that is necessary for blood to clot

19. Plasma Plasma is a key factor in maintaining homeostasis.
molecules diffuse into and out of plasma
contains proteins that stabilize blood volume
contains clotting factors
contains immune proteins

20. Platelets and different types of blood cells have different functions.
The bone marrow manufactures most of the blood components.
red blood cell
platelet
white blood cell

21. Red Blood Cells Most numerous cells in blood are red blood cells
Main function of red blood cells is to transport oxygen.
Red blood cells get their color from the iron in hemoglobin, a protein that binds oxygen in the lungs and carries it throughout the body
Red blood cells are disks that are thinner in their center than along their edge
Red blood cells circulate for an average of 120 days before they are destroyed in the liver and spleen.

22. Red blood cells make up 40-45 % of all blood cells.
transport oxygen to cells and carry away carbon dioxide
have no nuclei and contain hemoglobin

23. White Blood Cells
White blood cells guard against infection, fight parasites, and attack bacteria.
They are produced from stem cells in bone marrow and can live for years.
They are not confined to blood vessels—many white blood cells can slip through capillary walls to attack foreign organisms in different tissues

24. White blood cells fight pathogens and destroy foreign matter.
red blood cell
platelet
white blood cell

25. Protein markers define blood types and Rh factors.
ABO blood group the most common
Rh factor can be negative or positive
blood types must be compatible for transfusions

27. Platelets
Blood clotting is made possible by plasma proteins and cell fragments called platelets

28. Platelets help form clots that control bleeding.
fibrin
red blood cell
white blood cell

29. Platelets—How the help blood clotting
When platelets come in contact with the edges of a broken blood vessel, their surface becomes sticky, and they cluster around the wound
Platelets then activate enzymes to start blood clotting
Clot seals damaged area & prevents further blood loss

30. The Lymphatic System
As blood passes through capillaries, some blood cells and components of plasma move through capillary walls and into the fluid between cells, carrying nutrients, dissolved oxygen, and salts.

31. The Lymphatic System
Most of this fluid, known as lymph, is quickly reabsorbed into capillaries, but not all of it.
The rest goes into the lymphatic system, a network of vessels, nodes, and organs that collects the lymph, “screens” it for microorganisms, and returns it to the circulatory system.
The lymphatic system is also involved in the absorption of nutrients and in immunity.

32. Role in Immunity
Hundreds of small bean-shaped enlargements—called lymph nodes—are scattered along lymph vessels throughout the body
Lymph nodes act as filters, trapping microorganisms, cancer cells, and debris as lymph flows through them.
White blood cells inside lymph nodes engulf and destroy this cellular “trash.”

33. Role in Immunity
When large numbers of microorganisms are trapped in lymph nodes, the nodes become enlarged.
The “swollen glands” that are symptoms of certain kinds of infections are actually swollen lymph nodes.

34. The respiratory and circulatory systems work together to maintain homeostasis.
Oxygen-poor blood
Oxygen-rich blood
The respiratory and circulatory systems bring oxygen and nutrients to the cells.
The circulatory system transports blood and other materials.
brings supplies to cells
carries away wastes
separates oxygen-poor and oxygen-rich blood

35. The respiratory system is where gas exchange occurs.
picks up oxygen from inhaled air
expels carbon dioxide and water
nose
sinus
mouth
epiglottis
trachea
lungs

36. The respiratory system moves gases into and out of the blood.
The lungs contain the bronchi, bronchioles, and alveoli.
Millions of alveoli give the lungs a huge surface area.
The alveoli absorb oxygen from the air you inhale.
alveoli
bronchiole

37. Breathing involves the diaphragm and muscles of the rib cage.
Air flows from areas of high pressure to low pressure.
Air inhaled.
Muscles contract and
rib cage expands.
Diaphragm flattens
and moves downward.
Air exhaled.
Muscles and
rib cage relax.
Diaphragm relaxes
and rises.

38. Gas exchange occurs in the alveoli of the lungs.
The respiratory system exchanges oxygen and carbon dioxide.
Oxygen and carbon dioxide are carried by the blood to and from the alveoli.
oxygen diffuses from alveoli into capillary
oxygen binds to hemoglobin in red blood cells
carbon dioxide diffuses from capillary into alveoli
GAS EXCHANGES
ALVEOLI
alveolus
capillary
co2 o2
Co2 diffuses
into alveolus.
O2 diffuses
into blood.
capillaries

39. Breathing is regulated by the brain stem.
midbrain
pons
medulla oblongata
spinal chord

40. Respiratory diseases interfere with gas exchange.
Lung diseases reduce airflow and oxygen absorption.
Emphysema destroys alveoli.
Asthma constricts airways.
Cystic fibrosis produces sticky mucus.

41. Smoking is the leading cause of lung diseases.
Bronchitis, emphysema, cancer