Source: Defense notes PAP Systems of Defense Source: Defense notes PAP
How do animal systems interact to defend the body?
1st Line of Defense: non-Specific
INTEGUMENTARY SYSTEM Main Functions: Main Parts: Body’s first line of defense Keeps out foreign objects Helps control body temperature Main Parts: Skin Hair Nails Sweat and Oil glands
Cross-Section of Skin Contains keratin for elasticity and waterproofing Contains melanin for pigmentation Functional layer of skin that contains nerve cells, blood vessels, hair follicles, and specialized skin cells. Made mostly of fat Lies beneath the dermis acting as a shock absorber and an insulator. Anchors the skin to underlying organs
How does the integumentary system help with defense? Works with the Immune system as defense against pathogens. Protects underlying structures from Ultraviolet (UV) radiation Dehydration
What makes tattoos permanent? https://www.youtube.com/watch?v=DMuBif1mJz0
Occasionally threats make it past the wall…
IMMUNE SYSTEM Main Parts: Main Functions: Antibodies (protective proteins) T-cells (WBC) B-cells (WBC) Main Functions: B-cells produce antibodies that attack pathogens in the blood T-cells activate Killer Cells that will destroy the pathogen.
2nd Line of Defense: non-Specific
What happens if the pathogen gets past the 1st Line of Defense? 2nd Line of Defense-Non-Specific Inflammatory Response Local blood vessels dilate. Increased blood flow to the area brings more white blood cells Temperature Response Fever. Bacteria can only grow within a certain temperature range. A fever raises the temperature so the bacteria cannot survive. Complement System Made of about 20 different proteins Travels the bloodstream punching holes in the cell membranes of pathogens. Interferon, a protein released by virus-infected cells, prevents viruses from making proteins and RNA. White Blood Cells Neutrophils-engulfs and destroys pathogens Macrophages-ingest and kills pathogens and clears dead cells and debris Natural Killer Cells-attacks cells infected with pathogens, punctures their cell membranes
3rd Line of Defense: Specific
3rd Line of Defense: Specific Defenses Specialized Cells are activated to target and destroy pathogens.
How does the immune system help with defense? Needs Skeletal System to make White Blood Cells (WBC) in the bone marrow Needs Cardiovascular System to transports WBCs to site of infection (redness is increased blood flow)
CIRCULATORY SYSTEM RECAP Main Functions: Transports antibodies & white blood cells Transports toxins and waste products to be removed Main Parts: Blood vessels Heart Red & White blood cells (includes B- and T-cells)
How does the circulatory system helps with defense? Works with Immune system to transports White Blood Cell (WBC) to defend invaders. Works with excretory system to excrete toxins and waste out of the body. Works with nervous system during fight or flight response.
Skeletal System Functions
How does skeletal system help with defense? Protects soft organs Works with the immune system by creating white blood cells (WBC).
Cross-Section of Bone Spongy bone Compact bone Blood vessels Periosteum Porous inner core filled with red bone marrow Production of blood cells and platelets begins Hard outer covering Made of fat for energy storage. Tough exterior membrane Contains blood vessels Supplies nutrients to the bone Yellow Bone Marrow