https www yo utube comwatc h vs 5

https: //www. yo utube. com/watc h? v=s 5 i. Co. Caofc Circulatory System Ms. Day AP Biology

What is a Circulatory System? ¡It is a means of getting stuff around the body ¡Oxygen ¡Nutrients ¡Wastes

Do All Animals Have a Circulatory System? ¡NO ¡Some animals rely on only DIFFUSION to move substances throughout their bodies ¡NOT EFFICIENT; very slow ¡LIMITS SIZE – if you’re going to use diffusion to transport substances, then you have to be SMALL.

So How is a Circulatory System Different from Diffusion? ¡Involves a “pump” and some type of vessels (“plumbing”) to move materials more quickly and in large amounts throughout the body. ¡Also involves a tissue designed to carry some of these materials (ex: BLOOD)

Open Circulatory Systems ¡ARTHROPODS and most MOLLUSKS ¡Multiple cell layers diffusion is not adequate. ¡OPEN circulatory system ¡NO distinction between blood and fluid between cells (called interstitial fluid)

CLOSED Circulatory system ¡Annelida, some mollusks (squid/ocutopus) & vertebrates ¡Blood is in blood vessels and never leaves ¡Blood distinct from interstitial fluid ¡ 1+ hearts pumps blood into vessels that get smaller and smaller until reach organs. ¡Nutrients diffuse into organs; wastes from organs diffuse into blood vessels

Open vs. Closed Circulatory System

Basics of the Vertebrate Heart ¡Atrium – receiving chamber ¡Receives blood from some location ¡Not very muscular ¡May have 1 or 2 atria ¡Ventricle – pumping chamber ¡Pumps blood to some location ¡VERY muscular ¡May have 1 or 2

Types of Blood Vessels ¡Arteries (A for AWAY) ¡carry blood away from heart ¡Veins ¡carries blood back to heart ¡Capillaries ¡tiny blood vessels (arteries) ¡Gas exchange occurs here

Basics of Vertebrate Blood Vessels Structure ¡ 3 main types of blood vessels – Arteries, Veins and Capillaries ¡Arteries Arterioles – smaller branches of the arteries that take blood to capillaries ¡ Capillaries ¡Smallest vessels ¡Contained within organs ¡Thin walls ¡Diffusion of nutrients/oxygen into organs and wastes out of organs occurs here ¡ Venules – capillaries converge to create venules which carry blood to veins ¡ Veins

Birds and Mammals ¡Why do birds and mammals have the most efficient circulatory system? ¡ENDOTHERMS – maintain body temperature by using heat from metabolism ¡Requires LOTS of energy MORE oxygen per gram of body weight than other animals (ectothermic animals)

Mammalian Heart ¡Size of fist and under sternum in humans ¡Made of cardiac muscle tissue ¡ 2 atria with thin walls (A for Away) ¡Receiving chambers – deliver blood to ventricles ¡ 2 ventricles ¡Thick walls –pumps blood from heart to entire body (not just lungs) ¡Pumping chambers ¡Contains veins and arteries

The Heart This is a vein. It brings blood from the body, except the lungs. 2 atria 2 ventricles The heart has four chambers A A V V These arteries. They carry blood away from the heart. Coronary arteries, the hearts own blood supply

Heart Valves = prevent backflow of blood Artery to Lungs Vein from Head and Body Right Atrium Artery to Head and Body Vein from Lungs Left Atrium Valve Right Ventricle Left Ventricle

CIRCULATORY SYSTEM 17

Humans (& other mammals) have a circulatory system is a double circulatory system. This means it has two parts. Lungs the right side of the left side of the system deals with oxygenated blood. deoxygenated blood. Think: Love Left is oxygenated Body cells

Heart Valves = prevent backflow of blood Artery to Lungs Vein from Head and Body Right Atrium Artery to Head and Body Vein from Lungs Left Atrium Valve Right Ventricle Left Ventricle

Chambers of the Heart

Blood flow through the heart 1. 2. 3. 4. Into vena cava Into right atrium Down to right ventricle Out pulmonary artery to lungs ¨ 5. 6. 7. 8. Gets O 2 and dumps CO 2 Back to heart through pulmonary vein Into left atrium Down to left ventricle Out aorta to body

Largest artery Largest vein http: //sumanasinc. com/webcontent/animations/content/humanheart. html

TO BODY TO LUNGS FROM BODY E G F D A C B H FROM LUNGS

Mammalian Heart ¡When blood is pumped into the elasticwalled arteries, they stretch. ¡Pulse – rhythmic stretching of the arteries caused by pressure of blood driven by ventricles ¡Heart rate – number of times the heart beats per minute

Mammalian Heart ¡Heart sounds ¡Heard with stethoscope http: //www. sumanasinc. com/we bcontent/animations/content/blo ¡Caused by closing of valves odpressure. html ¡Lub-dup ¡Lub - created from recoil of blood against closed AV valves ¡Dup – created from recoil of blood against semilunar valves ¡Blood Pressure ¡Pushing of blood against walls of vessels

Two Main Parts of Circulatory System ¡Pulmonary Circuit ¡Blood goes from heart to lungs to pick up O 2 and release CO 2 ¡Systemic Circuit ¡Blood pumped out of heart to the rest of the body (systems) The path of the blood through the body is HEART LUNGS HEART BODY HEART

Pulmonary Artery: Only artery that carries DEOXYGENATED blood Pulmonary Vein: Only vein that carries OXYGENATED blood

The Circulatory System- The Pathway Pulmonary artery Pulmonary vein Lungs Head & arms Aorta Main vein Right Left Liver Digestive system Kidneys Legs

Blood flow through the body uses blood vessels Arteries ¡take oxygenated blood away from the heart ¡No valves ¡Break into capillaries ¡thicker 30

Capillaries ¡Very small vessels ¡Gases diffuse across very thin wall of small vessels ¡Gas exchanges here !!! O 2 and CO 2 ¡Carries oxygenated blood ¡Nutrients and oxygen leave the blood and go into the body tissue 31

Veins ¡takes deoxygenated blood back to heart ¡Have one-way valves 32

Blood Flow ¡Blood flows MUCH faster in aorta ¡ 30 cm/sec ¡Blood flows MUCH slower in capillaries (DECREASES in velocity)

Blood Flow ¡Seems like blood should actually accelerate in capillaries ¡Like putting your thumb over the end of a water hose ¡When you NARROW the opening, the velocity of the fluid must get faster to get the same volume through. ¡However, the total NUMBER of capillaries AND their TOTAL WIDTH TOGETHER makes them MUCH wider (when taken all together) than the single aorta. ¡Thus, velocity slows A LOT

Blood has 4 parts Red blood cell Platelets White blood cell Plasma

Red Blood Cells (Erthyocytes) A disc that is round and flat without a nucleus can change shape to an amazing extent, without breaking, as it squeezes single file through the capillaries. contain hemoglobin and iron, a molecule specially designed to hold oxygen and carry it to cells that need it.

White Blood Cells (Leukocytes) There are many different types and all contain a big nucleus. The two main ones are the lymphocytes and the macrophages. Macrophages “eat” and digest micro -organisms. Some lymphocytes fight disease by making antibodies to destroy invaders by dissolving them. Other lymphocytes make antitoxins to break down poisons.

Platelets are bits of cell broken off larger cells. Platelets produce tiny fibrinogen fibers to form a net. This net traps other blood cells to form a blood clot.

A strawcolored sticky liquid that carries the cells and the platelets which help blood clot; mostly water Plasma It also contains useful things like: • Carbon dioxide • Glucose • Amino acids • Proteins • Minerals • Antibodies • Vitamins • Hormones • Waste (urea)