Chapter 4 Notes

 A group of cells are called tissues  4 main types of tissue  Epithelial tissue- protects the body by covering internal and external surfaces. Shape: columnar, cubical or plate like  Connective tissue- supports and connects organs and tissue  Muscle tissue- contains cell material which has the ability to contract and move the body. Shape: long and spindle like in order to contract  Nervous tissue- contains cells that react to stimuli and conduct an impulse

 Membrane- formed by putting 2 thin layers of tissue together  Can be epithelial or connective  Epithelial membranes Mucous membranes Serous membranes Cutaneous membrane (skin)  Connective membranes Synovial membrane

 Line surfaces and spaces that lead to the outside of the body  Lines the respiratory, digestive, reproductive, and urinary systems  Provides mucus that lubricates the lining  Respiratory mucosa  Lines respiratory passages  Gastric mucosa  Lines the stomach  Intestinal mucosa  Lines the small and large intestines

 Double-walled membrane that produces a water fluid and lines closed body cavities  Fluid produced is called serous fluid  Parietal membrane is the outer part of the membrane that lines the cavity  Visceral membrane is the part that covers the organs within the cavity  Pleural membrane  Lines the thoracic cavity and protects the lungs. Fluid is called pleural fluid  Pericardial membrane  Lines the heart and protects the heart. Fluid is called pericardial fluid  Peritoneal membrane  Lines abdominal cavity and protects abdominal organs. Fluid is called peritoneal fluid

 Consist of two layers of connective tissue  Synovial membrane  Lines joint cavities  Secrete synovial fluid which prevents friction inside the joint cavity

 Organ- group of tissues  Organ system- group of related organs  10 organ systems in the human body  Body systems include:  Skeletal  Muscular  Digestive  Respiratory  Circulatory  Excretory  Nervous  Endocrine  Reproductive  Integumentary

 Tissue can be affected by infection or inflammation  Inflammation- protective response to an injury or irritant. Results in pain, swelling, redness, and loss of motion  Infection- refers to the invasion of a microorganism causing disease. Usually results in inflammation  Trauma  Resulting from an external force will cause tissue damage and injury  Most frequent cause of injury is car accidents  Abnormal growth of cells can alter tissue and cause damage and trauma  Birth defects can impair tissue

 Repair of damaged tissues occurs continually under everyday activities of living  Depending on the type and location of injury some tissue is quickly repaired  Muscle tissue heals slowly and bone tissue repairs are slow because broken bone ends must be kept aligned and immobilized until the repair is done  Heart muscle tissue does not repair itself  Nerve cells destroyed by infection or injury do not grow back

 2 types of epithelial tissue repair  Primary repair  Secondary repair

 Takes place in “clean” wounds  Clean wound- a cut or incision on the skin where infection is not present  New epithelial cells push themselves toward the surface of the skin  Wound is quickly restored to normal  If damage is over a large area connective tissue cells and fibroblasts are involved

 If a large area of skin is damaged, fluid will escape from broken capillaries  Fluid dries and seals the wound with a scab  Epithelial cells multiply at the edges of the scab and continue to grow over the damaged area until it is covered  If a deep area of skin is destroyed, skin grafts may be needed to help in wound healing  Primary repair of deep tissues  When damage occurs to deep tissues, the edges of the wound must be sewn together with sutures

 Granulation occurs in a large open wound with small or large tissue loss  This process forms new vertically upstanding blood vessels  Granulation causes the surface to have a pebbly type texture  As granulation occurs a fluid is secreted that has strong bactericidal properties that helps reduce the risk of infection during wound healing  Scar tissue (cicatrix) will usually form depending on the extend of tissue damage.  Newly growing tissues require lots of protein for repair  Some vitamins also play an essential role in wound repair