Blood

How do RBC's carry carbon dioxide

20% of the carbon dioxide carried in the blood is carried on hemoglobin. It doesn't bind to the iron, like oxygen does. It binds to the globin protein. When the globin picks up carbon dioxide it is then called carbaminohemoglobin.

What percent of blood volume are red blood cells, Platelets, Leukocytes

45% of blood volume is made up of RBC's. 55% of blood volume is made up of the plasma. Less than 1% is white blood cells. Less than 1% is platelets.

What percent of people in the U.S. are Rh+

85%

How much of blood plasma is water

99%

How long do platelets live

About 10 days

How long to RBC's live

About 100-120 days

What are some examples of proteins that occur in the blood plasma? What is the overall function of plasma proteins?

Albumin, Globulins, Antibodies, Fibrinogen. Proteins do two things: they transport things in the blood (oxygen, lipids, some hormones, and so forth), and they also contribute to maintaining isotonic conditions, just like the ions do.

What is a blood antigen? Antibody?

Antigens are things that the body perceives to be foreign nad mounts an immune response against. Examples might be toxins (snake venom), molecules on the surface of a foreign bacterial cell, viruses, cancer cells, the wrong type of RBC....

What do you need from your diet in order to build RBC's

B12, iron, amino acids, and folic acid.

What is the cell shape of red blood cells?What's the advantage of this shape?

Biconcave The advantage is more surface area for oxygen exchange in the lungs and in tissues.

What is the function of platelets

Blood clotting

Explain the cycle of oxyhemoglobin forming, then becoming deoxyhemoglobin.

Blood that isn't carrying much oxygen is moved to the lungs. Once there, oxygen moves from the lungs, into the blood. When oxygen attaches to the iron on the hemoglobin molecule, we then call the molecule oxyhemoglobin. Oxyhemoglobin then travels back to the heart. From there it is pumped out to the tissues/cells of the body. Once at the cells, oxygen is released from the hemoglobin and diffuses into the tissues. The hemoglobin is now called deoxyhemoglobin.

What type of tissue is blood

Connective tissue.

What organs secrete erythropoietin (EPO) What does this hormone do? What conditions cause EPO to be secreted?

EPO comes from the kidney. When it is produced, it stimulates the production of RBC's in the red bone marrow. If cells in the kidney become hypoxic (oxygen deficient), they stimulate the secretion of EPO.

Coagulation is the formation of a fibrin mesh. What is fibrin

Fibrin is a protein. Fibrin threads form a sticky bond between the platelets that are already in the plug. This forms what is called a fibrin mesh.

What are the two categories of WBC's

Granulocytes and Non-granulocytes

What is hematopoiesis?Where does it occur?

Hematopoiesis is the formation of the formed elements of the blood (RBC's, WBC's, and platelets). It occurs in the red bone marrow.

What are the components of a hemoglobin protein

Hemoglobin is made up of 4 globin proteins. Each globin protein has a heme pigment molecule. The heme binds to an iron ion (Fe++). The iron then binds to oxygen.

How does the blood act to protect us

If there is an injury, blood clotting stops the bleeding, protecting us from blood loss.

What part of the hemoglobin protein binds to oxygen

Iron

Describe the characteristics of blood

It is connective tissue. It has three types of cells: white blood cells, red blood cells and platelets. The pH is held within a range of 7.35-7.45. Blood is more viscous than water because of the cells in it (formed elements). The red blood cells are what cause blood to increase its viscosity. The more RBC's, the more viscous the blood will be. Blood is about 8% of our body weight. This is about 5-6 liters in men and 4-5 in women.

What percent of blood volume are leukocytes? What is their main function?

Less than 1% They function in immunity

Once RBC's wear out, what happens to them

Macrophages (cells of the immune system) engulf old RBC's. The globin proteins are broken down into amino acids and returned to the blood, then they are used to build other proteins that need to be made. Iron is recycled and used to build new RBC's. Heme is broken down into bilirubin, and secreted into the small intestine in the secretion called bile. It is excreted in the feces.

Do platelets have a nucleus

No

Describe platelet plug formation. Why don't platelets stick to the inner layer of the blood vessels (the endothelium)

Normally, the cells of the endothelium release nitric oxide and prostacyclin that prevent platelet aggregation. If the vessel wall is injured, the collagen fibers of the C.T. underneath adhere to the platelets.

How is a platelet related to a megakaryocyte

Platelets are fragments of megakaryocytes.

What is clot retraction

Platelets have contractile proteins (actin and myosin). The platelets contract, pull on the surrounding fibrin strands, squeezing serum out of them. This compacts the clot and draws the ends of the injured section of blood vessel together.

What are the three formed elements in blood

RBC's, White blood cells (WBC's), Platelets (Thrombocytes)

What determines the viscosity of blood

RBCs.

Describe red bone marrow.Where does it exist in adults?

Red bone marrow exists in the medullary cavity of long bones and in the spaces of spongy bone. In adults these areas are more limited as compared to children.

Describe how positive feedback is used to form a clot at the site of a blood vessel injury.

So, platelets aggregate and form a plug at the site of injury. Von Willebrand factor stabilizes the bonds between the collagen fibers and the platelets. Platelets become activated: they swell, form spiked processes, become stickier and release chemical messengers like ADP and serotonin. These cause more platelets to stick to the area. These new platelets become activated (sticky and release more chemicals), causing more platelets to stick to the area and become activated, which causes more of them to stick and activate.

Briefly describe how platelets are formed.

The megakaryoblast undergoes mitosis, but not cytokinesis. So, it becomes larger and is multi-nucleate. It matures into a megakaryocyte. The megakaryocyte streams cytoplasm, like little extensions off of the cell. These rupture and the little cytoplasmic extensions become the platelets. A plasma membrane forms around the new platelet.

Who is the universal donor? Universal recipient? Why?

The universal donor is type O. There aren't any antigens in this blood, so another body won't recognize anything foreign on these RBC's. There won't be any immune reaction mounted against this type. The universal recipient is type AB. These people don't have antibodies for any type, so they can accept anything without mounting an immune response.

What is fibrinolysis?Why is it important?

This is a process that removes clots after healing is complete. If these clots accumulate over time, the vessel might become blocked.

What is the function of erythrocytes

To transport oxygen from the lungs to the cells of the body and to transport carbon dioxide from the cells to the lungs.

Describe how you would blood type someone's blood. What would you mix together? What would an aggregated reaction tell you?

You would place antibodies for type A in one well, antibodies for type B in another well. Add your blood to both wells. If there is a reaction, it means that the antibodies reacted with the antigen. You will see a clumping or agglutination as a response.

What are the main things that blood transports

oxygen, nutrients like glucose and amino acids, carbon dioxide and wastes to and from cells. Transport hormones around the body.

What are the main regulatory functions of blood (3)

three things: body temperature. The blood moves heat around the body - it is a reservoir or holding place for heat. If we are cold it brings heat to the internal organs, making sure they stay warm. If we are hot, it takes the heat to the skin, where it can dissipate into the environment. Blood regulates body pH: it has many different chemicals in it that can buffer the blood. If the pH is too low, then it has too many H+ ions in it. HCO3- is one ion that is in the blood. It binds to the free H+, forming H2CO3, and bringing the pH back up toward normal. If there are too many OH- ions in the blood, then it becomes too alkaline or basic. In this case, OH- can bind to H+ to form water, bringing the pH back towards 7, or neutral. The blood regulates fluid volume in the circulatory system. Because there are at least 20 different proteins in the blood, it has osmotic potential or power. It attracts water towards it. Water moves into the blood, making sure that blood pressure remains high enough to move the blood throughout the system

What are the three functions of blood

transport, regulate, protection

What are the 4 different blood types possible?What antigens would each type have? What types of antibodies would each type have in their blood?

4 possible blood types are: A, B, AB, O. Type A would have antigens for type A. Type B has antigens for type B. Type AB has both A and B antigens. Type O doesn't have any antigens. Type A has type B antibodies. Type B has type A antibodies. Type AB doesn't have any antibodies. Type O has antibodies for type A and B.

What electrolytes are found in the blood, Why are they important in the blood?

Ca++, Na+, Cl-, K+, Mg++, HCO3- (bicarbonate) They are important for two reasons: First, they help buffer the pH of the blood and second, they help maintain isotonic conditions with the fluids outside the blood stream. This way, the blood doesn't lose or gain fluid, blood pressure remains stable.

The first step in hemostasis is vasoconstriction (vascular spasm). What is vasoconstriction and why is it a benefit

Damaged blood vessels constrict. The stimulus could be an injury, chemicals released by endothelial cells of the vessel, or chemicals released by activated platelets. This limits blood loss until a clot can form.

Why is it important to have just the right amount of red blood cells

If there are too many, then the blood gets too viscous and can cause a heart attack or stroke. If there aren't enough, then the blood gets too thin and not enough oxygen is delivered.

What else is dissolved in blood? What is the function of each? (Nitrogenous substances, nutrients, respiratory gases, and hormones).

Nutrients - to give to cells for fuel Oxygen - to transport to cells so that they can undergo cellular respiration. Carbon dioxide - taken from cells and delivered to the lungs to be expelled.Hormones - each has a different effect, but the blood transports hormones to their target cells.Nitrogenous wastes - these come from cells and are delivered to the kidney so that they can be expelled.

How is the structure of a RBC ideally suited for its function

There are no organelles (no nucleus, no mitochondria). These take up space. Without them, more oxygen can be held within each RBC. The mitochondria would use up the oxygen, so the lack of mitochondria means that more oxygen is delivered to tissues. Small size and shape - this means that there is a greater surface area for oxygen to move into and out of the cell. Biconcave shape - no part of the inside of the cell is far from the cell membrane, so any oxygen in the cell can easily diffuse out of the cell, or into it.

What role does platelet-derived growth factor play

This stimulates smooth muscle cells and fibroblasts to divide and rebuild the vessel wall. The fibroblasts form a C.T. patch underneath the vessel. The endothelial cells multiply and restore the lining of the vessel. Smooth muscle cells divide and restore the lining behind the endothelium.