A&PII CH 18 Circulatory sytem: Blood

Urea is an example of which of the following?

Nitrogenous waste

Which are transported in plasma?

Nitrogenous wastes Dissolved gases Nutrients

Why are only old RBCs destroyed in the spleen?

Old cells rupture in the narrow channels of the spleen because they are no longer flexible or resilient.

Which property of blood is defined as the total molarity of dissolved particles that cannot pass through the blood vessel wall?

Osmolarity

Choose the components of blood

Plasma Platelets RBC WBC

Which mechanisms are used by the body to prevent inappropriate clotting?

Platelet repulsion caused by prostacyclin Dilution of clotting factors Presence of anticoagulants such as heparin and antithrombin

The reproduction of fibroblasts and smooth muscles during injury repair is triggered by which of the following?

Platelet-derived growth factor

Which formed elements release vasoconstrictors, promote blood clotting, initiate dissolution of clots, and secrete growth factors?

Platelets

As platelets aggregate during the second step of hemostasis (shown in this picture), which of the following events occur?

Platelets degranulate resulting in release of thromboxane A, ADP and serotonin.

Which term refers to an excess of red blood cells?

Polycythemia

Which is another term for clotting factors?

Procoagulants

What is leukopoiesis?

Production of white blood cells

Platelets perform which of the following functions?

Release vasoconstrictors Promote clotting and also initiate dissolution of clots Release factors that attract WBCs

At which stage of erythrocyte development are the RBCs released into the blood?

Reticulocyte

Blood loss stimulates accelerated erythropoiesis. This may cause an increase in which of the following?

Reticulocytes

True or false: A total WBC count is more useful than a differential WBC count when trying to pin down the specific cause of a disease.

False

True or false: A, B, AB and O are the only blood groups.

False

True or false: Coagulation involves only two chemical reactions.

False

True or false: In most cases of bleeding, only the intrinsic mechanism of coagulation is activated.

False

The meshlike framework of a blood clot is formed by a sticky protein called ______.

Fibrin

Which best describes clot retraction?

Fibrin threads contract to pull the edges of the wound together.

Keeping in mind the structure of hemoglobin, name the nutrient that is critical for hemoglobin synthesis.

Iron

What is the functional role of platelet-derived growth factor (PDGF)?

It stimulates mitosis in smooth muscles and fibroblasts.

High levels of bilirubin in the blood lead to a condition called ______.

Jaundice

The alternate term for a white blood cell (WBC) is

Leukocytes

Decreased blood osmolarity could cause which of the following?

Low blood pressure Edema

Which term refers to the development of white blood cells?

Luekopoiess

What causes hemolytic disease of the newborn?

Maternal anti-D destroys fetal erythrocytes

Hypoxemia triggers the production of erythropoietin. Erythropoietin increased the rate of erythropoiesis. This an example of which of the following?

Negative feedback control

Which granulocyte is aggressively antibacterial, and has a band-shaped nucleus when young?

Neutrophil

What is the first response to a blood vessel injury?

Vascular spasm

What are the three hemostatic mechanisms? Select three answers from the list below.

Vascular spasm Blood clotting Platelet plug formation

Describe normal erythrocytes

-Contain hemoglobin to transport gases like oxygen -Have a biconcave shape

How does the body use iron?

-Nearly all cells use Fe2+ to make electron-transport molecules (cytochromes) in their mitochondria. -The muscles use Fe2+ to make the myoglobin. -The bone marrow uses Fe2+ for hemoglobin synthesis.

Which is true regarding the life cycle of erythrocytes?

-Production of red blood cells normally takes 3 to 5 days. -About 20 mL of packed RBCs are produced per day. -About one million red blood cells are formed per second. -An erythrocyte lives for an average of 120 days.

How do reticulocytes differ from mature red blood cells? Select all that apply

-RBCs are more numerous; only 0.5-1.5% of circulating blood cells are reticulocytes. -Reticulocytes have polyribosomes; RBCs do not.

Choose some functions of plasma proteins

-Transport of iron, copper, lipids, hydrophobic hormones -Clotting - Immune defense

Place the steps of iron metabolism in order. Start with iron intake, and finish absorption from the digestive tract

1. A mixture of Fe2+ & Fe3+ are ingested 2. Stomach acid converts Fe3+ to Fe2+ 3. Fe2+ binds to gastroferritin 4. Gastroferritin carries Fe2+ to intestines for absorption

List, in order, the stages of erythropoiesis. Start with the least differentiated cell type and end with erythrocytes

1. Hemopoietic stem cells 2. Colony-forming units 3. Erythroblasts 4. Reticulocytes 5. Erythrocytes

Place the steps of hemostasis in the correct order, starting with what happens first.

1. Vascular spasm 2. Platelet plug formation 3. Blood coagulation

Adult hemoglobin consists of which of the following?

2 alpha chains and 2 beta chains

The process of erythropoiesis normally takes how many days?

3-5

How many heme groups are there in each hemoglobin molecule?

4

One molecule of hemoglobin contains which of the following?

4 globin chains and 4 heme groups

What is the average volume of blood in an adult?

4 to 6 liters

Which erythrocyte cell-surface antigens determine a person's ABO blood group?

A & B

Which of the following most accurately describes a platelet plug?

A mass of platelets and trapped formed elements

What is vascular spasm?

A short-lived mechanism in which the damaged vessel narrows to minimize blood loss

Jaundice is a yellowing of the skin due to which of the following?

Accumulation of bilirubin

Platelet activation is an example of positive feedback. What does that mean?

Activating one platelet leads to the activation of another platelet, and then another.

Match each type of plasma protein to its role

Albumin: Solute transport, pH buffering, regulation of blood viscosity and osmolarity Globulin: Immunity Fibrinogen: Clotting

What is hemophilia?

An inherited disorder caused by a deficiency of clotting factors

Inadequate erythropoiesis or hemoglobin synthesis, hemorrhage, and increased RBC destruction are all common causes of the erythrocyte disorder called

Anemia

A person is considered Rh-positive (Rh+) if he has which antigen?

Antigen D

A person tells you that she has A+ blood. Which antigens are expressed on the surface of her RBCs?

Antigen D Antigen A

A person's specific blood type is based on which of the following?

Antigens expressed on the RBC plasma membrane

Carbohydrates, proteins, and water (as well as some other nutrients) are transported from the digestive system to the body's cells in which of the following fluids?

Blood plasma

Antigens on the surface of the erythrocyte membranes determine which of the following?

Blood type

Which of the following may cause hemolytic anemia?

Blood type incompatibilities Sickle cell disease, thalassemia, malaria Snake and spider venom Penicillin allergy

The cardiovascular (not circulatory) system includes which of the following?

Blood vessels Heart

Hemostasis usually involves which mechanism(s) of coagulation?

Both extrinsic and intrinsic

The extrinsic mechanism of coagulation is initiated by which of the following?

Factors released by damaged blood vessels (thromboplastin)

Which system includes the heart and blood vessels, but does not include the blood?

Cardiovascular

Which statement about clotting factors is true?

Clotting factors initiate a cascade of reactions.

Sarah is an abuser of antacids. What is a possible side effect of excessive antacid use?

Decreased absorption of iron by the intestine

Leukocytes called ______ of 1 function to destroy large parasites such as hookworms and tapeworms.

Eosinophils

What is the most abundant formed element of the blood?

Erythrocytes

Which blood cells are biconcave and lack a nucleus and other organelles?

Erythrocytes

Which blood cells are critical to survival because of their ability to transport oxygen?

Erythrocytes

Hypoxemia, resulting from hemorrhage, high altitude, or emphysema, may stimulate which of the following?

Erythropoiesis

Which is a hormone that stimulates erythrocyte production?

Erythropoietin

Under normal circumstances only 0.5 - 1.5% of the circulating blood cells are reticulocytes. Which medical condition might cause this number to increase?

Excessive blood loss

Which may activate platelets?

Exposed collagen

What is the first procoagulant that the extrinsic and intrinsic pathways have in common?

Factor X

Which clinical measurements express the blood's ability to carry oxygen?

Hematocrit Hemoglobin concentration RBC count

Iron is a crucial component of which of the following?

Hemoglobin Cytochromes Myoglobin

Malaria can cause which type of anemia?

Hemolytic

Which term refers to the production of blood, especially the formed elements?

Hemopoiesis

Which lists the stages of erythropoiesis starting with the least differentiated cell type?

Hemopoietic stem cell --> colony-forming unit--> erythroblast

Which term refers to limiting blood loss from an injured vessel?

Hemostasis

Which can cause anemia?

Inadequate hemoglobin synthesis Hemorrhage Increased hemolysis

Which of the following is the most common ion found in the blood?

Sodium

Old blood cells usually die as they pass through what organ?

Spleen

What is the role of erythropoietin?

Stimulates RBC production

Iron needs to be in the Fe2+ form to be absorbed. Which of the following converts Fe3+ to Fe2+?

Stomach acid

The hematocrit and hemoglobin concentration are clinical data that describe which of the following?

The amount of oxygen the blood can carry

Following the first pregnancy with an Rh+ fetus, the immune system of an an Rh- woman produces anti-D antibodies. During her next pregnancy the baby is at risk of developing Hemolytic Disease of the Newborn (HDN), but only if which of the following is true?

The baby's blood is Rh+.

Why don't platelets normally stick to the endothelium?

The endothelium is coated with prostacyclin which repels platelets.

What is factor X?

The first factor shared by the extrinsic and intrinsic pathways

The term hemopoiesis refers to which of the following?

The production of blood

What is hemolysis?

The rupture of red blood cells

Which statement about blood groups is true?

There are many blood grouping schemes that describe over 500 antigens.

What happens to the fragments of old red blood cells after they rupture?

They are recycled by macrophages.

Which statements are true about neutrophils?

They are the most abundant leukocyte. They have multi lobed nuclei when mature.

What role do macrophages play in RBC death and disposal?

They separate the heme from the globin of hemoglobin, and hydrolyze globin into free amino acids.

How is fibrin formed?

Thrombin converts inactive fibrinogen to fibrin.

What is the purpose of a differential WBC count?

To determine the number and ratio of each type of leukocytes in a sample

True or false: Erythrocytes circulate for about 120 days before they die

True

An individual with both A and B red blood cell antigens has which ABO blood type?

Type AB

An individual with B antigens on their RBCs, but no A antigens, has which ABO blood type?

Type B

An individual with neither A nor B red blood cell antigens has which ABO blood type?

Type O

Which is a nitrogenous waste that is transported in the plasma?

Urea

A generalized condition in which there is too little hemoglobin or too few erythrocytes is called ______.

anemia

The interaction of protein factors to produce a clot is called ______.

coagulation

As part of coagulation, the plasma protein called ______ is converted to fibrin.

fibrinogen

What is thrombopoiesis?

formation of platelets

The clotting cascade that originates from within the blood itself is called the ______ pathway.

intrinsic

A lack of intrinsic factor and/or vitamin B12 may cause the form of anemia called ______ anemia.

pernicious

When collagen in the wall of a blood vessel is exposed as a result of injury, ______ adhere and develop long, spiny pseudopods which draw the vessel walls back together.

platelets

Blood vessel linings are very smooth and coated with the chemical ______, which prevents platelet adhesion and unwanted clotting.

prostacyclin

The process by which clots become more compact is called clot ______.

retraction

What is hemostasis?

stoppage of bleeding

The enzyme ______ converts fibrinogen into fibrin.

thrombin

The process of platelet formation is called ______.

thrombopoiesis

True or false: Iron deficiency anemia can be caused by poor nutrition or blood loss.

true