Human Anatomy and Body Systems

1. Human Anatomy and Body Systems

2. Levels of Organization Remember, the human body is organized in several levels, from the simplest to the most complex. . . Cells – the basic unit of life Tissues – clusters of cells performing a similar function Organs – made of tissues that perform one specific function Organ Systems – groups of organs that perform a specific purpose in the human body ***The purpose of the 11 organ systems is for the human body to maintain homeostasis.

3. The 11 Human Body Systems The 11 human body systems are as follows: -- nervous system -- integumentary system -- respiratory system -- digestive system -- excretory system -- skeletal system -- muscular system -- circulatory system -- endocrine system -- reproductive system -- lymphatic (immune) system

4. The Digestive System Function:to convert food particles into simple molecules that can be absorbed into the blood and used by the body Major Organs and their Functions: Mouth – to chew and grind up food (mechanical) -- amylase in the saliva begins the chemical breakdown Esophagus – pipe connecting mouth to stomach Stomach – secretes pepsin, an enzyme that breaks down food. The stomach has a pH of 2.

5. SmallIntestine – after digestion is complete, the chyme (processed stomach contents) enters the small intestine where it is absorbed into the bloodstream by the help of small hairs called villi.

6. Large Intestine – removes water from the chyme and gets the waste ready for excretion The nutrients that are absorbed during digestion travel into the Circulatory System to be distributed through the body!

7. Liver – produces bile, which breaks down fats in foods. This is an accessory organ. Gallbladder – pouch-like organ that stores bile for future use

8. The Digestive System

9. Explain how the Digestive system works closely with the: Circulatory system Muscular system Endocrine system

13. The Excretory System Kidneys-Ureter-Bladder-Urethra Function: to rid the body of wastes, including excess water and salts

14. Major Organs of excretion Kidneys – the main organ of the excretory system; excretion begins here -- Kidneys filter the blood, removing wastes

15. More excretory organs: • Skin – sweat glands remove excess water and salts from the body • Lungs – expel the waste product carbon dioxide (cellular respiration) • Question: Can one organ be part of TWO systems?

17. Explain how the excretory system works closely with the: Circulatory system Integumentary system Homeostasis

18. The Nervous System Function: to coordinate the body’s response to changes in its internal and external environment The basic unit of structure in the nervous system is the neuron (nerve cell)

19. Major Organs of the Central Nervous System • Brain – control center of the body • Divided into 2 halves • Controls conscious activities, intelligence, memory, language, muscle movement, senses

20. Brain stem controls breathing and heart rate Medulla oblongata reacts to increased CO2 levels to increase rate of breathing

21. Spinal Cord – sends instructions from the brain to the rest of the body and vice versa -- any organism with a major nerve cord is classified as a chordate • Nerves – conduct impulses to muscle cells throughout the body

22. Explain how the nervous system works closely with the: Integumentary system Muscular system Endocrine system

23. Which 2 body systems are working together in this image?

24. The Circulatory System Function: to deliver oxygen to the body and brain; to deliver nutrients from the digestive system.

25. Image of the Circulatory System

26. Heart – the major muscle of the circulatory system • pumps blood through its four chambers (two ventricles and two atria) • pumps deoxygenated blood into the lungs, where it gets oxygenated, returns it to the heart, and then pumps out through the aorta to the rest of the body • valves regulate the flow of blood between the chambers

28. Arteries – carry blood away from the heart and to the major organs of the body Veins – carry blood back to the heart away from the major organs of the body Capillaries – small blood vessels (one cell thick) where gas exchange occurs, connects arteries and veins

29. Red Blood Cells: contain hemoglobin; carries oxygen throughout body White Blood Cells: fight disease Platelets: fragments that help blood clot Plasma: liquid part of the blood

30. Explain how the circulatory system works closely with the: Respiratory system Digestive system Endocrine system

31. The Respiratory System Function: to provide the body with a fresh supply of oxygen for cellular respiration and remove the waste product carbon dioxide

32. Major Organs • Nose – internal entry and exit point for air • Trachea – the “windpipe” • Bronchial Tubes – the two large passageways that lead from the trachea to your lungs (one for each lung) • Alveoli – clusters of tiny sacs where gases are exchanged with the bloodstream.

33. Diaphragm - the muscle that causes you to breath Cilia – tiny hairs that line the air passages that trap tiny particles

34. The respiratory system and circulatory system work closely together:

35. Explain how the respiratory system works closely with the: Circulatory system Muscular system Endocrine system

36. Function:works with the skeletal and nervous system to produce movement, also helps to circulate blood through the human body The Muscular System

37. Muscle contractions can be: Voluntary: skeletal muscles Involuntary: smooth (intestinal) muscles, cardiac muscle Major Skeletal Muscles -- biceps (flexor) -- triceps (extend) -- deltoids -- rectus abdominus -- gluteus maximus -- hamstrings

38. Over 600 muscles in your body • Control movement • Voluntary: you choose to move them • Involuntary: controlled unconsciously by the brain Which muscle would raise this arm? Straighten the arm?

39. Explain how the muscular system works closely with the: Circulatory system Skeletal system Nervous system

40. Integumentary System • Comprised of the largest organ in the body which is our skin. Hair and nails are also in this system. Functions: • Skin is our first line of defense against disease. It also helps regulate body temperature, excretes wastes through sweating, and maintains homeostasis in a variety of ways.

41. Integumentary Examples of human HOMEOSTASIS: • Sweating • Shivering • Thirst • Increased/decreased breathing • Increased/decreased heart rate

43. Explain how the integumentary system works closely with the: Circulatory system Nervous system Excretory system

44. The Skeletal System Function:to provide structure and support to the human body Bones are where new blood cells are generated (in the marrow), and require the mineral calcium for strength Major Bones of the Human Body -- femur (thigh bone) -- humerus (upper arm) -- radius and ulna (lower arm) -- cranium (skull) -- sternum (breastbone) -- clavicle (shoulder blade) -- fibula and tibia (calf) -- vertebrae (back) -- scalpula (shoulder) -- pelvic bone

45. Axial Skeleton: (white) skull, ribs, spine • Appendicular Skeleton: (purple) arms, legs, pelvis

46. Bones are living tissue • There are 206 bones in the human body • The skeletal system works closely with the muscular system (the muscles move the bones)

47. Explain how the skeletal system works closely with the: Respiratory system Muscular system Endocrine system

49. The Lymphatic (Immune) System Function:to remove infectious diseases and other pathogens from the human body The lymphatic system transports tissue fluid (called lymph) and filters out disease-causing pathogens (through lymph nodes)