Regents Biology Circulatory System in Animals

Regents Biology WHY DO WE NEED A CIRCULATORY SYSTEM?

Regents Biology TRANSPORT ! Unicellular organisms can remove wastes and absorb nutrients through their cell __________________ They are in direct contact with their environment

Regents Biology TRANSPORT !  Multicellular organisms have layers and layers of cells which are not in direct contact with the environment  Developed a system to transport nutrients to cells and wastes away from cells  The Circulatory System!  What does it mean to circulate??

Regents Biology  The job of the circulatory system is to transport nutrients to and remove wastes from cells

Regents Biology Human Circulation Includes:  Blood: liquid transport material with cells  Heart: a muscular pump to move the blood  Blood vessels: arteries, capillaries and veins that deliver blood to all tissues

Regents Biology The Circulatory System Analogy  The heart – the engine  Blood vessels – the roads  Blood – the bus

Regents Biology Misconceptions

THIS IS NOT YOUR HEART.

Regents Biology THIS IS YOUR HEART.  About the size of your first.

Regents Biology While we’re on it… NEVER  Your blood is NEVER blue.

Regents Biology Brain Pop!  ystems/circulatorysystem/ ystems/circulatorysystem/

Regents Biology  Why do we need a circulatory system?  supplies in  fuel (sugars)  digestive system  oxygen  respiratory system  waste out  CO 2  respiratory system  need to pick up & deliver the supplies & wastes around the body  circulatory system Feeding Energy Needs

Regents Biology Circulatory System  Organ  heart  Tissues & cells  blood vessels  arteries  veins  capillaries  blood  red blood cells  plasma (liquid)

Regents Biology Vertebrate Heart  4-Chambered heart  atria (atrium)  thin wall  collection chamber  receives blood  ventricles  thick wall pump  pumps blood out right atrium left atrium right ventricle left ventricle

Regents Biology Evolution of circulatory system fishamphibianreptilesbirds & mammals AA V V VV V AAAA A V 2 chamber3 chamber 4 chamber Not everyone has a 4-chambered heart

Regents Biology AV SL AV Lub-dub, lub-dub  4 valves in the heart  flaps of tissue  prevent backflow of blood  Heart sounds  closing of valves  “Lub”  force blood against closed AV valves  “Dub”  force of blood against semilunar valves  Heart murmur  leaking valve causes hissing sound  blood squirts backward through valve

Regents Biology

Have a heart? Ask Questions!!

Regents Biology Circulatory System Blood Vessels

Regents Biology Study Skills - Vessels  Arteries – A AWAY! Carry blood away from the heart  Veins – return blood to the heart  CapiLLaries – smaLLest blood vessels

Regents Biology Arteries: Built for their job  Arteries  blood flows away from heart  thicker walls  provide strength for high pressure pumping of blood  elastic & stretchable

Regents Biology Coronary artery bypass bypass surgery

Regents Biology Veins: Built for their job  Veins  blood returns back to heart  thinner-walled  blood travels back to heart at low speed & pressure  why low pressure?  far from heart  blood flows because muscles contract when we move  squeeze blood through veins  valves in large veins  in larger veins one-way valves allow blood to flow only toward heart Open valve Blood flows toward heart Closed valve

Regents Biology

 The veins have valves that prevent back-flow of blood.

Regents Biology Structure-function relationship  Capillaries  very thin walls  allows diffusion of materials across capillary  O 2, CO 2, H 2 O, food, waste body cell O2O2 food waste CO 2

Regents Biology Blood Flow  Blood flows from the heart to large arteries which branch likes trees to smaller and smaller arteries  At their narrowest vessels are capillaries where materials can be exchanged between cells and the blood  Blood flows from small capillaries to small veins which meet up with other small veins to form large veins

Regents Biology Red Blood Cell in a Capillary Notice that one red blood cell can barely fit in a capillary! 2f/A_red_blood_cell_in_a_capillary%2C_pancreatic_tiss ue_-_TEM.jpg/250px- A_red_blood_cell_in_a_capillary%2C_pancreatic_tissue _-_TEM.jpg

Regents Biology  2 part system  Circulation to lungs  blood gets O 2 from lungs  drops off CO 2 to lungs  brings O 2 -rich blood from lungs to heart  Circulation to body  pumps O 2 -rich blood to body  picks up nutrients from digestive system  collects CO 2 & cell wastes Circulation of Blood heart lungs body Circulation to lungs Circulation to body

Regents Biology Stops along the way…  Lungs  pick up O 2 / clean out CO 2  Small Intestines  pick up nutrients from digested food  Large Intestines  pick up water from digested food  Liver  clean out worn out blood cells

Regents Biology More stops along the way…  Kidneys  filters out cell wastes (urea)  extra salts, sugars & water  Bone  pick up new red blood cells  Spleen  pick up new white blood cells

Regents Biology Lymphatic System  Returns lost fluid back to the blood  Fluid lost is called lymph  Lymph nodes (your glands) filter bacteria and dead cells out from the lymph  Cause of “swollen glands”

Regents Biology

Have a heart? Ask Questions!!

Regents Biology Circulatory System Blood

Regents Biology Blood & blood cells  Blood is a tissue of fluid & cells  1. plasma  liquid part of blood  dissolved salts, sugars, proteins, and more  Cells  2. red blood cells (RBC)  transports O 2 in hemoglobin  3. white blood cells (WBC)  defense & immunity  4. platelets  blood clotting

Regents Biology Blood Composition  Plasma 55% (mostly water)  Blood Cells 45%

Regents Biology Blood Cell Production ribs, vertebrae, breastbone & pelvis  Stem cells  “parent” cells in bone marrow  develop into all the different types of blood cells  red blood cells  white blood cells white blood cells red blood cells white blood cells

Regents Biology Red blood cells  Small round cells  produced in bone marrow  5 liters of blood in body  5-6 million RBC in drop of human blood  last 3-4 months (120 days)  filtered out by liver  ~3 million RBC destroyed each second

Regents Biology Red Blood Cells  Do NOT have a nucleus  Can NOT reproduce on their own, they only come from bone marrow  Hemoglobin  Protein which carries O 2  250,000 hemoglobin proteins in one red blood cell O2O2

Regents Biology White Blood Cells  Largest blood cells  About 8,000 per drop of blood  Formed in the bone marrow or in the lymph tissue  Protect the body against diseases by forming antibodies (a plan for killing antigens) or engulfing bacteria  Antigen – foreign invader

Regents Biology

Types of White Blood Cells  1. Phagocytes - engulf bacteria and viruses by phagocytosis  (see next slide)  2. Lymphocytes - produce antibodies which clump bacterial poisons or bacteria  antibodies (a plan for killing antigens)

Regents Biology Remember: Phagocytosis

Regents Biology Platelets - Blood clotting protein fibers build the clot emergency repair of circulatory system platelets seal the hole chemical emergency signals

Regents Biology STUDY SKILLS  Red blood cells – Are bowl shaped and carry Oxygen  White blood cells – destroy foreign invaders, think of a doctors white lab coat!  Platelets – form a PLATE over cuts to stop blood loss

Regents Biology Have a heart? Ask Questions!!

Regents Biology Cardiovascular disease  Atherosclerosis & Arteriosclerosis  deposits inside arteries (plaques)  develop in inner wall of the arteries, narrowing their channel  increase blood pressure  increase risk of heart attack, stroke, kidney damage normal arteryhardening of arteries

Regents Biology Heart Disease  Heart disease and coronary artery disease are the leading causes of death in the US.  Causes in most cases are unknown, although stress, obesity, high salt intake, and smoking can add to a genetic predisposition.  No cure--may be treated by medication, exercise & diet.  "Silent killer"--millions don't know they have it

Regents Biology Clogging Artery tery_1.gif

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Regents Biology Cardiovascular health bypass surgery  Risk Factors  genetics  diet  high animal fat  exercise & lifestyle  smoking  lack of exercise

Regents Biology Heart Disease Heart disease death rates Adults ages 35 and older

Regents Biology Women & Heart Disease  Heart disease is 3rd leading cause of death among women aged 25–44 years & 2nd leading cause of death among women aged 45–64 years. Risk factors  Smoking  Lack of exercise  High fat diet  Overweight Death rates for heart disease per 100,000 women, 2002

Regents Biology  3.) Stroke – interruption of blood flow to all or part of the brain -- may be caused by blockage to a blood vessel or a ruptured blood vessel

Regents Biology 4.) Leukemia -- white blood cell cancer -- many kinds Some Causes - virus, radiation, chemical exposure

Regents Biology  Some symptoms: frequently sick, higher than normal total number of WBC's

Regents Biology  Treatments include: radiation, chemotherapy, bone marrow transplants