1. Internal Organs Structure & Function

2. Heart & Respiratory System

3. Heart: -Located in the left center of the chest, below the ribcage & sternum, between lungs. -Size of a clenched fist

4. Heart: A muscular organ
Consists of 4 chambers: right & left atria and right & left ventricle
Each chamber is separated by a valve to prevent blood from flowing the wrong way
Primary Function:
Circulates oxygenated blood throughout the body to the working tissues
A single heartbeat consists of contraction of both atria followed by contraction of both ventricles
Path of blood flow:
Right side pumps blood to lungs to become oxygenated blood
Left side pumps blood to the rest of the body
Back from body -- into Right Atrium- into Right Ventricle - To the Lungs-- Back to the Left Atrium- To the rest of the body!

6. Conduction System
Specialized electrical conduction system controls the contraction of the heart
Called the Purkinje Fibers

7. Electrocardiogram P wave : atrial depolarization (contraction)
QRS Complex : ventricle depolarization / contraction
T wave : ventricle repolarization

9. Key Terms Bradycardia : fewer than 60 beats per minute
Tachycardia : greater than 100 beats per minute
Stroke Volume (SV): amount of blood ejected with each beat
Cardiac Output : the volume of blood ejected per minute from the heart
Cardiac output = SV x HR
Artherosclerosis : excessive build up of cholesterol in the heart arteries, which blocks blood flow
Maximal Heart Rate :
220 – (a person’s age in years)= max. heart rate

10. Lungs: -Located within the ribcage; 2 sides (or lobes), made of elastic tissue

11. Lungs:
Deliver oxygenated blood to the tissues of the body through gas exchange!
Oxygen to Carbon Dioxide
Oxygenation of blood
2 lungs sitting in thoracic cavity
Under rib cage, anterior to the heart
Weigh approximately 1 kg
Volume : 4-6 Liters of air
Huge surface area
If spread out, lung tissues would cover half of a tennis court
Highly vascularized area

12. Respiratory Pathway Mouth or Nose Trachea Bronchioles Bronchi Lungs
Alveoli

13. Alveoli Lungs contain more than 300 million alveoli.
Thin-walled, membranous sacs
Receive largest blood supply of all organs!

14. Alveoli

15. Alveoli
Millions of thin-walled capillaries (blood) and alveoli (air) lie side by side
Gas diffuses across the thin barrier

16. Exercise Exercise increases the total lung capacity
Better shape = more efficient gas exchange
Max VO2 = maximal oxygen consumption
The region where oxygen consumption plateaus during exercise
Measures a person’s aerobic fitness

17. The Lymphatic / Immune System
How the Body Fights Against Disease

18. The Network of Channels

19. The System Network of channels with specialized tissues and organs
Lymph organs : spleen, tonsils, & thymus
Lymph nodes

20. The Channels The vessels are very low in pressure
Connect lymph nodes and the organs
About 3 Liters of lymph enter the blood stream every 24 hours

21. The Warriors Lymphocytes are created in red blood cells
Protect the body against foreign substances
Macrophages help the immune system by gobbling up foreign substances and activate the lymphocytes

22. Lymph Nodes Clusters of the lymphatic channels
Filters lymph as it heads to the bloodstream
Activates the Immune system if needed!

23. Lymphoid Organs
Thymus : early years, secretes hormones to fight against certain diseases
Tonsils : “invite” infections in to trap the bacteria

24. The Spleen: -Largest Lymph organ in the body -Located under the diaphragm on the left side

25. The Spleen: Resevoir for Red Blood Cells
Regulates number of Red Blood Cells in Circulation
Destroys ineffective Red Blood Cells
Produces antibodies & Lymphocytes
Cleans blood and is on immune system surveillance

27. Digestive Organs

28. Digestive Organs: Stomach Small Intestines Large Intestines Pancreas
Liver
Gallbladder

29. Stomach: -Found in left quadrant, between esophagus and small intestines

30. Stomach: Storage and mixing chamber for ingested food
Some digestion & absorption occur here
Gastric secretions assist in the partial digestion of proteins and alcohol & caffeine
Food is mixed with secretions from stomach glands to form Chyme, which then passes into the small intestines

31. Small Intestines: -Found between the stomach and large intestines -3 Portions: Duodenum, Jejunum, & Ileum -20 feet in length

32. Small Intestines:
Chyme mixes with secretions from the liver & pancreas
Chyme moves through the small intestines over a period of 3-5 hours, propelled by peristaltic contractions
Most digestion and absorption occurs in the small intestines

33. Large Intestines: -Connected to the small intestines -3 divisions: Cecum, Colon, & Rectum -6 ½ feet long

34. Large Intestines:
Chyme is converted into feces through the absorption of water, secretion of mucus, & activity of microorganisms

36. Pancreas: -Located between small intestines & the Spleen

37. Pancreas:
Secretes Pancreatic juice, critical in digestion of protiens, fats, & carbohydrates
Produces insulin and glucagon, controls the amount of sugar & amino acids in the blood

38. Liver: -Largest internal organ in the body -Found in upper right quadrant, underneath the diaphragm -Weighs about 3 pounds

39. Liver: Consists of 2 lobes Performs digestive & excretory functions
Absorbs & stores excessive glucose
Processes nutrients
Detoxifies harmful chemicals
Secretes bile, essential in neutralizing & diluting stomach acid and digesting fat

40. Gallbladder: -Pear-shaped, saclike structure found underneath the liver

41. Gallbladder: Storage reservoir for bile secreted by the liver
Secretes stored bile into the small intestines after a meal

42. The Urinary System

43. Kidneys: -Situated on either side of the spine, in center of the back

44. Kidneys:
Primary function is to filter metabolic wastes, ions, or drugs from blood and expel them from the body via urination

45. Bladder: -Hollow organ, lies posteriorly to the Pubic Symphysis

46. Bladder:
Stores Urine