WHAT ARE THE FOUR FUNCTIONS OF BLOOD Functions

WHAT ARE THE FOUR FUNCTIONS OF BLOOD?

Functions of Blood Carries oxygen from lungs to body cells and carbon dioxide from cells to lungs Carries waste products to kidneys Carries nutrients to body cells Fights infection and helps heal wounds

WHAT MAKES UP BLOOD? (it’s 8% of your body mass, and adults have about 5 L of it!)

Parts of the blood Plasma Red blood cells White blood cells Platelets

Plasma Liquid part of blood made mostly of water Half the volume of blood Nutrients, minerals, and oxygen are dissolved in plasma to be carried to body cells Carries waste to kidneys to be disposed

Red Blood Cells 5 million red blood cells in 1 cubic mm of blood No nuclei Contain hemoglobin: molecule that carries oxygen and carbon dioxide Last about 120 days 2 -3 million cells are made in your bone marrow each second

Red Blood Cells

White Blood Cells 5, 000 – 10, 000 cells per cubic mm of blood Fight bacteria and viruses that invade body Body reacts to invaders (illness) by creating more of them Can last a few days or many months

White Blood Cell (far right)

Platelets Irregularly shaped cell fragments that help clot blood When you cut yourself, platelets stick to wound and release chemicals that form clot to plug blood vessel Allow skin to repair itself without losing more blood 400, 000 in one cubic mm of blood Live for 5 -9 days

Platelets

WHAT ARE THE POSSIBLE BLOOD TYPES?

Blood Types A B AB O

WHICH IS THE UNIVERSAL DONOR? WHICH IS THE UNIVERSAL RECEIVER?

Blood types Universal donor: O (has no antigens, so it doesn’t cause other blood types to clot) Universal receiver: AB

Rh Factor Protein present in red blood cells of most people Represented by + or – + means you have the Rh factor, - means you don’t People with Rh- blood can’t get transfusions from Rh+ blood – will produce antibodies that lead to clotting If a mom with Rh- blood is pregnant with baby with Rh+ blood, she must receive injections to prevent production of antibodies that fight Rh+

Blood diseases Anemia: problem with red blood cells stops body tissues from getting enough oxygen to function Possible causes: large loss of blood, diet lacking iron, side effect of other disease (Celiac) Sickle-cell anemia: red blood cells are C-shaped instead of disc-shaped and don’t move easily through blood vessels, causing clotting Leukemia: white blood cells are made in excessive numbers Cells are immature and don’t fight infection well Fill bone marrow and crowd out normal cells

Assignment – Choose one! Pretend you are Miss Frizzle. Take the class on a tour of the circulatory system with the Magic School Bus. Must be original, not just imitating the actual magic school bus video Can work in group of 3 max. Pretend you just got a job for Web. MD. Create the FAQ page for someone who wants to know more about their circulatory system or about a specific illness related to circulation and blood. Minimum of 8 FAQ and answers written in complete sentences

Lymph Lymph: tissue fluid that has diffused into capillaries Found in between cells Made mostly of water and dissolved substances Contains lymphocytes: white blood cell that helps your body fight off disease

Lymphatic System The lymphatic system is responsible for removing fluid from the body’s cells Carries lymph through network of lymph capillaries and vessels, and drains it into large veins near the heart No heart-like structure to pump lymph – moves because of smooth muscle contractions

Lymphatic System Lymph passes through lymph nodes before it enters blood Lymph nodes: bean-shaped organs throughout the body that filter out microorganisms and foreign materials Lymph nodes fill with lymphocytes when you fight an infection Become red, warm, and sensitive to touch

Lymphatic Organs Tonsils: back of throat, protect body from harm entering through the mouth Thymus: located behind sternum, makes lymphocytes Spleen: located behind stomach, filters old red blood cells from blood