AP BIO HEART & BLOOD

What is blood?

• Blood is a liquid

• Contains plasma, cellular and formed elements such as erythocytes (RBC), leukocytes (WBC), and thrombocyte (platelets)

Red Blood Cells (erythrocytes):

• Mature RBCs don’t have a nucleus

• Live for about 90-120 days

• Only one type of RBC

• Erythrocytes contain hemoglobin, which is a protein that transports oxygen and is responsible for the red color of the blood. 

• Transport oxygen (oxyhemoglobin is responsible for the pale red color)

• Transports carbon dioxide

• Transports nitic oxide 

White Blood Cells (Leukocytes):

• 5 different types of WBC divided into two groups

Granular

- Neutrophil (first line of defense in our body, phagocytic) (stain lilac color) (two - five lobes connected by thin strands) - another name is polymorphonuclear

- Basophils (least common leukocyte) (irregular S-shape, large, dark, purple, variable sized granules)

- Eosinophil (Nucleus with 2-3 lobes connected by a thin strand) (stain orange red with ciclic dye)

Agranular:

- Monocyte (phagocytic) (largest of the wbc, differentiate into different macrophages)

- Lymphocyte 2 types  (agranulocyte) (dark oval to round nucleus) (increase in number during viral infections) 

     - Larger than erythrocytes with a prominent nucleus; use the bloodstream as transportation; don’t perform their functions within the blood

     - 

How blood is formed: 

• Eythropoetin is a hormone produced by the kidney. This is a steroid that produces RBc production through a process called erythropoesis

• Too many blood cells = polycytemia

• Blood clots can be stationary or an embolous one

• Thrombus can block blood flow and lead to death

Thrombopoietin (TPO)

• Hormone from the liver stimulates platelet formation

Stem cell = pleuripotent stem cells or hemocytoblast

• Humans and other vertrabaes have a closed circulatory system called the cardiovascular system.

• Arteries branch into arterioles and carry blood capillaries

• Networks of capillaries called capillary beds are the sites of chemical exchange between the blood and interstitial fluid

• Venules converge into veins and return blood from 

• capillaries to the heart

• Vertebrate hearts contain two or more chambers.

• Blood enterns through an atrium and is pumped out through the ventricle

• Atria-recieve blood

• Ventricles- pump blood

Heart Valves:

• Semi-lunar valve- passway between your heart's ventricles (lower chambers) and arteries

• Triscupid valve- located between the right artium and the right ventricle

• Pulmonary valve - located between the right ventricle and the pulmunoray artery

• Aortic Valve - 

Humans have a 4 chambered heart

• The heart contractcs and relaxes in a rhythmic cycle called the cardiac cycle

• The contraction, or pumping, phase is called systole

• Pulmonary artery is the only artery that transports deoxygenated blood from the heart to the lung.

• Pulmunary veins in the only vein that will transport oxygenated blood from the lungs to the heart….

Test hints:

• Red blood cell (five statement say which one is false) (be careful about moving of materials through the cells)

- RBC (erythrocytes) move oxygent through the body by passively transporting it across their cell membrane using a protein called hemoglobin. 

- Also carry carbon dioxide waste back to the lungs making their primary function the transport of gases via diffusion.

• Function of the circulatory system

- transport blood, oxygen, nutrients, and hormones throughout the body while simultaneously removing waste products like carbon dioxide

• Know why animals in the lower phylum don't have a circulatory system

- Their small size and simple body structure allow for the direct exchange of nutrients, oxygen, and waste products with their environment through diffusion. This means they don’t need a specialized system to transport these substances. - Close enough to the external environment to acquire what it needs directly. 

• Know everything about the open circulatory system

- A system where blood mixes with intersticial fluid and it’s pumped into a body cavity. The mixture of blood and fluid is called hemolymph.

- Heart pumps hemolymph into a cavity called hemocoel, the hemolymph fills the hemocoel and surrounds all cells, the hemolymph bathes the organs directly with oxygen and nutrients, hemolymph returns to the heart through openings called ostia, muscular movements by the animal during locomotion can facilitate hemolymph movement

- Found in arthropods and mollusks

- Examples of animals with open circulatory: snails, clams, roaches, spiders, dragonflies, lobsters, sea scallops

• Know the differences between the arteries and veins

- arteries carry blood away from the heart, while the veins carry it towards the heart

- arteries carry oxygenated blood and veins carry deoxygenated blood

- arteries have tick walls with muscle tissue, veins have thinner walls and use valves to keep blood flowing.

• Animals that have a three-chambered heart and its advantage 

- amphibians and most reptiles; frogs, lizards, and snakes except for crocodiles

- Advantages = more efficient blood circulation, less energy expedenture, suitable for aquatic environments, and evolutionary adaptation

- mix oxygenated blood and deoxygenated blood in the singe ventricle

• What is the name of the blood vessel that brings blood from the head to the heart

- The vena cava

• Know the difference between oxygenated and deoxygenated blood and what vessels it transports from

- oxygenated blood = higher concentration of oxygen 

- Deoxygenated blood = lower concentration in oxygen, higher concentration in  carbon dioxide

- However, pulmonary veins and arteries are exceptions as pulmonary arteries carry deoxygenated blood from the heart to the lungs, and pulmonary veins carry oxygenated blood from the lungs to the heart.

- arteries carry oxygenated blood away from the heart into the body, while veins carry deoxygenated blood back to the heart

• Largest vessel in the body (know something)

-  The aorta is the largest vessel in the body

- responsible for carrying oxygenated blood from the left ventricle of the heart to the rest of the body

- it’s elastic structure helps maintain blood pressure and smooth blood flow throughout the systemic circulation

• Valves are important to know

- Tricuspid valve: 

-Bicuspid valve

- Pulmonary valve

- Aortic semilunar valve:

• Know something about capillaries,, veins, venules, arteries and arterioles

• Know something about the heart beat (systole, diastole)

- Diastole represents ventricle filling, and systole represents ventricular contraction/ejection

- Systole is when the heart contracts and pumps the blood out

- Diastole is when the heart relaxes and fills with blood

- BP = systolic/diastolic

• Cardiac output 

- number of blood pumped out the heart in one minute

- The cardiac output is the volume of blood pumped into the systemic circulation per minute and depends on both the heart rate and stroke volume

• Where the pacemaker is found

- In the chest, just below the collarbone

- SA node is considered the pacemaker of the heart

• SA Node, AV node, bundle of his

- SA Node generates an electrical signal that causes the upper heart chambers to contract. The signal them passes through the AV node (atrioventicular) to the lower heart chambers (ventricles). 

- Bundle of his = the part of the electrical impulses that travel through the heart.

• Know something about blood pressure

- Blood pressure is typiccally measures in millimeters of mercury

- higher cardiac output increases BP

- sphygmomanometer is the device used to measure bp 

- Hypotension = low blood pressure, hypertension = high blood pressure

• Capillary bed 

- A network of small blood vessles that allow the exchange of gas, water, and nutrients 

- Located in metabolic organs such as lungs, kidneys, and the brain to exchange vital materials and get rid of waste

• Know about formed elements of blood and plasma

- (Everything listed above)

• Blood proteins

• Blood cells and phagocytes 

- Phagocytes is a specific type of white blood cells that destroy bacteria and debri through a process called pahgocytosis. 

- Types of phagocytes = neutrophil and macrophages 

• Know something about anemia and leukemia

- Anemia: caused by inadequate red blood cell production

- Leukemia: caused by genetic changes in the blood cells produced in the bone marrow cells 

• Know something about clotting the blood

 - platelets and proteins in the plasma will work together to stop the bleeding by forming a clot over the injury