Good bacteria Bacteria and Humans Majority of the

Good bacteria Bacteria and Humans • Majority of the bacteria humans come in contact with are helpful or neutral to humans. • The human digestive system contains billions of beneficial bacteria that • Aid in digestion and nutrient absorption • Synthesize vitamins • Limit the growth of harmful bacteria and excess yeast (fungi) • Help maintain homeostasis in the body • Probiotics are bacteria that provide healthy benefits to humans by improving or restoring digestive bacteria (added to food like yogurt or as a supplement) Bad bacteria • Only a small amount of bacteria cause harm to humans. • Foodborne illness • Bacterial infections (strep throat, sepsis, tuberculosis etc. ) • Some bacterial infections can cause nausea, vomiting, feeling bloated, loss of appetite, damage tissue, release toxins in the body, and other symptoms

Harmful Bacteria • When the animal body is infected with harmful bacteria, it will respond in multiple ways to fight infection. • Body’s response to harmful bacteria in the body include: § Increased white blood cell count § Increased body temperature – to kill bacterial cells § Swollen lymph nodes (may cause sore throat) as pathogens are filtered out of the body fluids • Bacterial infections are treated with antibiotics • Antibiotics can be developed from studying organisms like fungi that have developed toxins to kill bacteria • Antibiotics kill ALL bacteria in the digestive tract (good & bad) this leads to side effects in patients taking antibiotics like stomach cramps & yeast over growth (candida)

Levels of Organization in the Body: Cells Tissue Organ System Cell: Basic unit of structure and function; Cells are specialized for their specific function. Tissue: Group of cells working together to perform a specific function Organs: Group of tissues working together Organ System: Group of organs working together. All components interact to maintain homeostasis. *Cells are used to repair tissue *Cells and tissue repair organs

Integumentary System Cells: Skin Cells, Hair Cells, etc. Tissues: Epithelial (Epidermis) Connective (in the dermis) Organs: Skin (made of epidermis and dermis) Hair Nails Functions: • Protection • Serves as a barrier against infection and injury • Skin protects us from UV radiation • Hair protects our openings from dust/small particles • Regulation of body temperature • Sweat glands produce sweat too cool us down • Hair helps keep us warm

Immune System/Lymphatic System Cells: White Blood Cells (leukocytes, macrophages) Lymphocytes (B and T cells) Tissues: Bone Marrow Lymphoid Tissue Organs: Thymus, Liver, Spleen, Appendix, Lymph nodes, Skin (integumentary) Immune / Lymphatic Response: Antibodies bind to antigens; attacking the pathogen. White blood cells –seek out and destroy disease-causing organisms or substances -made/stored in the thymus, spleen, and bone marrow Functions: • Helps protect the body from disease • Work with the integumentary system • Skin is the first line of defense • Collects fluid (lymph) lost from blood vessels and returns the fluid to the circulatory system. • Lymph nodes act as filters, trapping bacteria and other microorganisms; swelling is a response to active lymph nodes.

Circulatory (Cardiovascular) System Cells: Red Blood Cells White Blood Cells Platelets (cell fragments) Functions: Transportation of materials to and from cells: o Delivery of oxygen (Red blood cells); removal of CO 2 -Works with Respiratory System Tissues: Muscular Tissue (in the heart) Connective Tissue Epithelial Tissue Organs: Heart, Arteries, Veins, Capillaries, Lungs (respiratory and excretory) o Delivery of nutrients; removal of wastes -Works with Digestive and Excretory systems o Delivery of Hormones - Works with Endocrine System to regulate body functions o Transports white blood cells - Works with immune system o Regulation of body temperature; blood vessels dilate to release heat o Protection; Platelets form blood clots

Skeletal System Cells: osteocytes, osteoblasts (bone cells) Tissues: Connective tissues -Ligaments - Hold bones together in a joint. -Tendons - Hold muscle to bone -Cartilage- cushions joint bones Bone marrow (produces red/white blood cells) Organs: Individual bones Functions: • Supports the body • Protects internal organs • Allows movement • Works with the muscular system • Stores mineral reserves (calcium) • Provides a site for blood cell formation (marrow)

Muscular System Cells: myocytes (muscle cells): skeletal, smooth and cardiac -Contain actin and myosin filaments that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion. Functions: Tissue: muscle tissue: skeletal, smooth and cardiac Organs: muscles, ex. Biceps, triceps, gluteus maximus -Made of: muscle tissue, blood vessels, tendons, and nerves. • Supports the body • Protects internal organs • Allows movement (with help from Muscular System) • Stores mineral reserves (calcium) • Provides a site for blood cell formation (marrow)

Nervous System Cells: nerve cells (neurons), brain cells -neurons transmit electrical impulses Tissues: nervous tissue, Organs: Brain, spinal cord, nerves Function: Coordinates the body’s response to changes in its internal and external environments.

Respiratory System Cells: lung cells, etc. Tissues: epithelial tissue Organs: nose, lungs, trachea, pharynx, larynx • Function: • Provide oxygen needed for cellular respiration and remove excess carbon dioxide from the body. • Works closely with the Circulatory System to transport these gases through the body. • Considered part of the excretory system, as it rids the body of CO 2

Endocrine System Cells: alpha, epithelial, follicular, etc. Tissues: epithelial tissue, adipose tissue Organs: Hypothalamus, pituitary gland, thyroid, pancreas, kidney, adrenal gland, etc. ALL PRODUCE HORMONES!!! Function: Controls growth, development, and metabolism; maintains homeostasis. Hormones - Chemicals that are released in one part of the body that travel through the blood stream and affect the activities of cells in other parts of the body. -controlled by feedback mechanisms. -Examples: erythropoietin (kidney), insulin (pancreas) The collection of glands that produce hormones that regulate metabolism, growth and development, tissue function, sexual function, reproduction, sleep, and mood, among other things. Works with all other organ systems.

Reproductive System Cells: sperm and egg Tissues: fibrous, erectile, muscular Organs: Female - ovaries, fallopian tubes, uterus, vagina, mammary glands, breasts Male - scrotum, testes, sperm ducts, prostate gland, penis Function: sexual reproduction Female 1. Produce egg cells (gametes) 2. Protect and nourish the offspring during gestation and after birth. Male - Produce and deposit sperm (gametes) Nervous system, muscular, endocrine, and reproductive system interacting during child birth.

Digestive System Cells: epithelial, D cells, etc. Tissues: epithelial tissue, muscular, connective Organs: Mouth, Esophagus, Stomach, Small intestine, Large intestine, Anus, Liver, Pancreas, Gallbladder Function: • Breaks down (digests) food -Chemical digestion: uses enzymes to break down food -Mechanical digestion: chewing/muscle contractions • Absorbs nutrients • Eliminates solid waste

Chemical Digestion (Enzymes) Enzymes are catalysts - they speed up chemical reactions & reduce activation energy. Enzyme: Protein Substrate: Food molecule that enzymes break down Products: Products from the reaction (smaller pieces of food)

Excretory (Urinary) System Cells: pore, canal, duct cell Tissues: epithelial tissue, muscular Organs: Kidneys (filter waste) Large intestine Liver Skin (sweat glands) Bladder Lungs (Respiratory - CO 2 waste) Function: • Eliminates waste products to maintain homeostasis. • Waste can be liquid (urine, sweat) or gaseous (CO 2)