1. Human Body Systems

2. Levels of Organization
Cells
Tissues
Organs
Organ Systems

3. Cells The basic unit of all living things.
Specialized cells perform a particular function.

4. Tissues
Tissues are groups of similar cells that perform a single function.
4 Types:
Connective
Muscle
Nervous
Epithelial
Bone
Adipose
Cardiac
Muscle
Skeletal
Muscle
Neural
Tissue
Cartilage

5. Organs
An organ is a group of tissues that work together to perform a complex function.
Examples:
Heart
Eye
Brain
Stomach

6. Homeostasis
The organ systems are working constantly to maintain a controlled, stable environment = Homeostasis.
Homeostasis in the body is maintained by feedback loops.

8. Circulatory System

9. Circulatory System Consists of:
Heart Blood vessels Blood

10. 5 Functions of the Circulatory System
Carries nutrients from the digestive system to cells.
2. Carries O2 from lungs to cells.
3. Carries waste products to the urinary system.
4. Carries CO2 from cells to lungs
5. Carries immune cells that help fight disease.

11. Atrium Upper chambers of the heart
Right atrium receives oxygen- poor blood from body
Left atrium receives oxygen-rich blood from the lungs

12. Circulation Through the Body
The heart functions as two separate pumps

13. Pulmonary Circulation
Oxygen-poor blood from the right side of the heart goes to the lungs.

14. In the lungs...
Carbon dioxide leaves the blood and goes into the alveoli of lungs. Oxygen is absorbed into the blood on red blood cells (hemoglobin)

15. Systemic Circulation
Oxygen-rich blood from the left side of the heart goes to the rest of the body.

16. After cycling through the body
Oxygen-poor blood returns to the right side of the heart and the cycle starts over.

17. Valves
Flaps of connective tissue between atria and ventricles. Allows for one direction of blood flow.

18. 3 types of Blood Vessels
Arteries Capillaries Veins

19. Arteries Large vessels Carry blood from heart to tissues of body
Thick walls - need to handle the high pressure

20. Capillaries Smallest blood vessels
Walls only one cell thick (endothelium)
Bring nutrients and O2 to tissues and absorbs CO2 and waste from tissues

21. Veins Carry blood from tissues back to heart
Blood in veins do not have oxygen
Walls of veins contain connective tissue and smooth muscle

22. Cells in the Blood
Blood is a circulating tissue consisting of three types of cells.
Red blood cells -
Transports O2 & CO2
White blood cells -
Immune system
Platelets -
Clotting

23. Break Time!

24. Respiratory System

25. Components Nose Pharynx Epiglottis Larynx Trachea Bronchus Bronchiole
Alveoli
Diaphragm

26. Mechanics of Breathing Inhalation
Air inhaled
Rib cage rises up
Diaphram contracts downward
Active process

27. Mechanics of Breathing Exhalation
Air exhaled
Rib cage lowers
Diaphram relaxes and domes upward
Passive process

28. Gas Exchange in the Lungs
Gas exchange into blood occurs in the alveoli/capillaries

29. Nervous System

30. Gas Exchange at Inner surface of alveoli
O2 dissolves in moisture
Diffuses across wall of air sac
Enters capillary
O2 binds hemoglobin on RBC
CO2 diffuses from cells/tissues to capillary
CO2 carried by blood to alveoli
CO2 diffuses out of blood to inner surface of alveoli
CO2 exhaled out of lungs

31. Break Time!

32. Nervous System

33. Nervous System
Purpose: The Nervous System controls and coordinates functions throughout the body and responds to internal and external stimuli

34. Parts of the Nervous System
Central Nervous System:
Brain and Spinal Cord
Peripheral Nervous System: The rest of the nerves in the body

35. Parts of a Neuron

36. Action Potential
Neuron is stimulated by another neuron or by the environment.
Positively charged sodium ions flood in and the inside becomes temporarily more positive.
As the impulse passes, potassium ions flood out restoring the resting potential.

37. What happens when the impulse reaches the end of the neuron?
The axon terminal ends at the synapse

38. Synapse
A structure that permits a neuron to pass a electo-chemical signal to an adjacent neuron.

39. What happens at the Synapse?
The electrical activity is converted into the release of a chemical (neurotransmitter), which binds to receptors

40. 3 Types of Neurons
Sensory
Interneuron
Motor

41. Sensory Neuron
Sensory neurons carry impulses from the senses to the brain and spinal cord

42. Interneuron
Interneurons connect sensory and motor neurons and carry impulses between them

43. Motor Neuron
Motor neurons carry impulses from the brain and spinal cord to muscles and glands

44. Break Time!

45. The Human Immune System

46. Disease
Any change (other than injury) that disrupts the normal function of the body
Pathogen is a disease-causing agent
Can be bacteria, viruses, fungi, protists, worms

47. How Are Diseases Spread?
Infected animals
Physical Contact
Contaminated Food and Drink

48. First Line of Defense

49. Second Line of Defense

50. Third Line of Defense Immune Response (Specific Defense)

51. Two Divisions of the Immune System
Humoral Immunity
Cell-mediated Immunity
Antibodies mark infected cells for death
Cells attack infected cells

52. Humoral Immunity
B-Cells - provides immunity against pathogens found in body fluids. Plasma cells make antibodies

53. Antigen
A substance on the surface of a pathogen that triggers an immune response is called an Antigen (Germ’s fingerprint)

54. Antibody
Antibodies are proteins that recognize and bind to antigens

55. Cell-Mediated Immunity
T-Cells - provide a defense against abnormal cells and pathogens inside living cells

56. Memory Cells
Some B-cells become memory cells, which are the antibody factory pre-programmed to respond to a returning antigen (i.e. vaccination)

57. Break Time!