1. Multicellular Body Organization http://www.merck.com/mmhe/sec01/ch001/ch001a.html

2. Why is teamwork important? What are the advantages of being the best at your job? Why do animals have organized bodies? What is the advantage of being multicellular?

3. Multicellular Levels of Organization Cells Tissues Organs Organ systems Organisms

4. Levels of Organization Multicellular organisms are put together with small building blocks called cells. The cells are first put together into tissues. Tissues are organized into organs. Organs work together in teams called organ systems. The organ systems work together to maintain homeostasis and health in the organism. Homeostasis can be thought of as a healthy balance of food, water, and energy between the organism and the environment

5. Types of Cells Muscle Red blood cells White blood cells Nerve cells

6. Muscle Cells STRUCTURE Strong, flexible, fibrous (long and thin) FUNCTION Muscle cells allow movement

8. Blood Cells RED BLOOD CELLS STRUCTURE Disk-shaped, small, flexible, smooth FUNCTION Carry oxygen through tiny blood vessels to each individual cell Carry carbon dioxide away from each cell

9. Blood Cells WHITE BLOOD CELLS STRUCTURE Flexible, round, can change shape like an amoeba FUNCTION Move between cells, surround, engulf, and destroy bacteria or viruses Protect us from infections

11. Nerve Cells STRUCTURE Specialized for communication Long, thin with fine extensions FUNCTION These cells send information from the brain to the body and back

12. Where do all these cell types come from? DNA in every cell of an animal is identical. However, each cell only uses part of the information in the DNA. Originally we begin as a single cell, as we grow our cells develop and “choose” what type of cell they become. (SPECIALIZATION) Once they choose, they cannot change again.

14. Do cells work alone? No, they work as teams. Each team, called a tissue, has a special job. There are four main types of tissues: nervous, muscle, epithelial, and connective.

16. What does connective tissue do? Holds body parts together Provides support, protection, strength, padding and insulation Examples: Joints, ligaments, tendons, fat tissue, blood

18. What does epithelial tissue do? Acts as a boundary between body parts. Acts as a boundary between the organism and the environment. Covers all inner and outer surfaces Examples: Skin, lining of your mouth, lining of your intestines

20. What does muscle tissue do? Provides movement for the body Muscle tissue can contract, or shorten, and relax. Examples: Biceps, triceps, quadriceps, gluteus maximus

22. What does nervous tissue do? Sends messages from one part of the body to another part of the body Sends messages from the brain to the body Sends messages from the body to the brain Examples: found in the brain, spinal cord, and nerve bundles

24. Do tissues work alone? Actually no, they work as teams too. A team of tissues is called an organ. Organs has specialized jobs to do for the organism. Examples: brain, lungs, heart, stomach

25. The Brain Largest organ in the nervous system Controls other organ systems of the body Made of 15-30 billion nerve cells Controls the actions of the body Collects information from the senses and “interprets” it. The brain is mainly made of “nerve” cells and nervous tissue. Connective tissue holds it together and connects the nerve cells.

26. The Lungs Transports oxygen from the atmosphere to your blood Releases carbon dioxide from your blood into the atmosphere The lungs are the largest organ in the respiratory system. The lungs are mainly “epithelial” tissue. Epithelial cells have a large surface area.

27. The Heart Largest organ in the cardiovascular (or circulatory) system. Pumps your blood through veins, arteries, and capillaries. Your heart is about the size of your fist. The heart is made of a special type of muscle tissue, called cardiac muscle. Connective tissue holds it together and nerves control the heartbeat.

28. The Stomach Digests food after chewing and swallowing. Produces stomach acid and enzymes to break food into small pieces. The muscle wall moves the food around breaking it up into smaller pieces. The stomach is made of muscle tissue, lined with epithelial tissue, held together by connective tissue and controlled by the nervous system.

29. Do all organisms have organs? Plants-root, stem, leaf, flower, seed, fruit, cone Fungi-sexual organs, food absorbing organ called “haustoria” Protists-unicellular, they do not have organs, they do have some “specialized areas” inside the cell, like the “eyespot” in the Euglena Bacteria-unicellular organisms do not have organs.

30. Organs work as teams too! Organ teams are called organ systems. Nervous system Respiratory system Circulatory system Digestive system

31. Nervous System Structures: Brain, spinal cord, retina, nerves Function: Send signals from one cell to another cell Send signals from one body part to another body part Control the body Process stimulus information and respond Process information from the senses. Sense “pain” or “danger”

32. Nervous System

33. Respiratory System STRUCTURES Lungs, nose, mouth, diaphragm (a muscle under the lungs that helps you breathe) FUNCTIONS The lungs exchange oxygen and carbon dioxide between the body and the atmosphere through diffusion. Oxygen is absorbed and sent to cells on the red blood cells Carbon dioxide is excreted and sent out

34. Respiratory System

35. Cardiovascular System STRUCTURES Blood, heart, and blood vessels make up this system FUNCTIONS Move the blood around the body. Blood contains red blood cells, white blood cells, water and nutrients that each cell needs. It is a delivery system.

36. Cardiovascular System

37. Digestive System STRUCTURES Teeth, esophagus, stomach, small intestine, large intestine FUNCTIONS Take in food (ingestion) Break down food (digestion) Move food nutrients, as molecules, to the cells (absorption) Removal of unusable food (excretion)

38. Digestive System

39. Why are we put together this way? Specialized Organized Structure Function Homeostasis Cells Tissues Organs Organ systems Multicellular organism What is the advantage of being multicellular?

40. Why are we put together this way? Multicellular body organization works constantly to maintain the balance needed for the survival of the organism. HOMEOSTASIS Regulation of body temperature Regulation of sugar levels Regulation of fluid levels

41. How is the human body like a city?