BI122 periard Exam #1

What are the 3 components of the cardiovascular system?

What are the 3 components of the cardiovascular system?

Blood

Heart

Blood Vessels

What are the 5 functions of blood?

1: Transportation (of:)

-Oxygen

-Carbon Dioxide

-Nutrients

-Waste products

-Hormones - from endocrine glands

2: Regulation: (of pH and electrolytes in the ECF)

3: Restrict Fluid Loss: (if vessel is damaged clotting occurs to stop fluid loss)

4: Defense: (against pathogens and toxins.)

5: Stabilization: (of body temp)

How does blood help stabilize body temperature?

Increase in body temperature = vessels transport blood to the skin & heat is lost.

Decrease in body temperature = vessels transport blood to vital organs & heat is conserved.

What are the formed elements of blood?

erythrocytes, leukocytes, platelets

What is hematocrit?

% of formed elements out of the total blood volume.

Why do males have a larger blood volume than females?

Due to average body sizes, males typically have more muscle mass and require more blood flow.

What are the 2 main components of plasma?

Plasma is composed of 92% WATER and 8% PLASMA SOLUTES; forms about 55% of whole blood.

Examples of plasma solutes

Plasma proteins (Albumins, Globulins, Fibrinogen, Enzymes and Hormones)

-Nutrients/wastes

-Respiratory Gases

-Electrolytes

Which plasma protein is more abundant? And which plasma protein is a major contributor to osmotic pressure?

Albumins; a major contributor to osmotic pressure

- to maintain water balance between tissues and blood-

What is hematopoiesis? (hemopoiesis)

A process that produces formed elements.

*before birth - occurs in yolk sac, spleen, and liver

*after birth - occurs in red bone marrow.

What are hemocytoblasts and what is their function?

They are multi-potent stem cells, found in red bone marrow, producing all formed elements after stimulated by hormones

percentage of erythrocytes in blood

~45%

percentage of leukocytes in blood

1%

Percentage of platelets in the Blood

1%

Function of RBCs (erythrocytes)

Transports respiratory gases.

Characteristics of erythrocytes

Anucleate

Bioconcave shaped

Mostly hemoglobin

What actually binds to oxygen?

Heme binds to O2

Why is carbon monoxide dangerous?

It binds with hemoglobin, reducing the blood's oxygen carry-capacity

What is erythropoiesis? And how are they controlled?

RBC formation; Regulation of Erythropoiesis = hormonally controlled. -Affected by low or high O2 levels in blood

life of an erythrocyte

Nutrients are absorbed in small intestine

Blood transports nutrients to red bone marrow

RBM erythrocytes arise from hemocytoblasts.

Erythrocytes life span = 120 days

Macrophage destroys old erythrocytes

What is jaundice and what causes it?

Yellowish discoloration of skin and eyes due to increased circulation of bilirubin in peripheral tissues

-> Due to liver not processing bilirubin or bile ducts blocked

Erythropoietin, Is it positive or negative feedback?

EPO is a hormone that stimulates RBC production; released by kidneys. -Negative feedback

What is blood doping?

the injection of oxygenated blood into an athlete before an event in an attempt to enhance athletic performance.

How does blood doping relate to erythropoiesis

basically adding more blood to body after it made new ones = bad

What is anemia?

Abnormally low oxygen-carrying capacity of blood.

iron deficiency anemia

anemia resulting when there is not enough iron to build hemoglobin for red blood cells; most common type!

pernicious anemia

Vitamin B12 deficiency = prevents stem cell division in red bone marrow

sickle cell anemia

results from abnormally shaped hemoglobin -usually genetic

What determines a blood type?

antigens on surface of RBC

What is an antigen?

Substance on a RBC that triggers a protective defense mechanism called an immune response

Agglutination

Process of clumping RBC that occurs when antigens on RBCs of one blood type are exposed to the corresponding antibodies (agglutinins) of another blood type

ABO blood group system

What blood type is the universal donor?

O

What blood type is the universal recipient?

AB

What antibodies do people not make until after exposure to a certain RBC antigen?

anti-Rh

hemolytic disease of the newborn

anti-Rh antibodies of a sensitized Rh- mother, cross the placenta and destroy the RBC'S of a Rh+ baby, leading to fetal anemia.

RhoGAM

drug prevents a mother's blood from becoming sensitized to foreign antibodies from her fetus

Leukocytes

have nuclei, no hemoglobin, make up little % of blood, spend its time outside bloodstream

Ameboid

WBC movement like an amoeba

diapedesis (emigration)

they can change shape to squeeze into and out blood through the endothelium (blood vessel lining cells)

positive chemotaxis

movement toward a chemical stimulus leading them to damaged tissue and invading pathogens.

Phagocytosis

they can engulf and digest pathogens (Neutrophils, eosinophils, and monocytes can phagocytize)

Granulocytes

neutrophils, basophils, eosinophils (names refer to granules' certain stains)

Agranulocytes

lymphocytes, monocytes. (small specific granules in cytosol not visible under microscope - a = without)

Never Let My Engine Blow

60, 30, 8, 2, 0

Neutrophils

A type of white blood cell that engulfs bacteria and is most abundant.

Eosinophils

Engulf antibody-labeled material

Increase during allergic reactions and parasitic worm infections

Release chemical mediators to destroy parasitic worms

Basophils

A circulating leukocyte that produces histamine when entering damaged tissue because it promotes inflammation...(also least abundant)

Lymphocytes

A type of white blood cell that make antibodies to fight off infections...T and B cells....

Have a dark stained nucleus

Monocytes

Leave circulation, enter tissue, and differentiate into Macrophages. Kidney shaped nucleus and phagocytize pathogens

Macrophages

leukocyte that destroys damaged or worn RBCs; activates lymphocytes to mount an immune response; actively phagocytic

What is leukemia?

Group of cancers that usually begin in red bone marrow and result in abnormal white blood cells.

Leukocytosis

Abnormal increase/elevation of WBC (due to infection or stress)

Leukopenia

Abnormally LOW white blood cell count

What are platelets?

Small fragments of cells that help blood clot

Phases of Hemostasis (stopping of a bleed)

1. Vascular phase

2. Platelet phase

3. Coagulation phase

vascular phase

endothelium releases chemicals that attract platelets to the site and stimulate cell growth and repair;

Promote vasoconstriction ("squeeze")

vasoconstriction

the constriction of blood vessels, which increases blood pressure.

Platelet phase

1: Platelets flowing by stick to damaged area = Adhesion

2: Platelets stick together forming a temporary PLUG = Aggregation

Coagulation phase of hemostasis

blood clotting; conversion of circulating fibrinogen into fibrin... --- forms the true clot!

Fibrinogen

plasma protein that is converted to fibrin in the clotting process

hydrostatic pressure

moves solutes and water out of capillaries and into interstitial fluid; occurs at arteriole end of a capillary

osmotic pressure

solutes (albumin) creates a pressure that draws water back into capillaries; occurs at venule end of a capillary

semilunar valves open

As ventricles contract and intraventricular pressure rises, blood is pushed up against semilunar valves, forcing them open.

What is clot retraction?

which is a process that pulls the cut edges of the vessel together -part of coagulation phase (retract vessels together)

What is fibrinolysis? How is TPA involved?

the enzymatic breakdown of the fibrin in blood clots; TPA is a drug that immediately dissolves clots "clot buster" helping restore blood flow to brain.

What is an embolus?

Blood clot freely floating in bloodstream - which can cause strokes.

What is hemophilia? What causes it?

inherited bleeding disorders caused by lack of clotting factors; bleeding severely...-affects males more often

pulmonary circuit

pumps blood to and from lungs (right side pumps into it)

systemic circuit

pumps blood to and from body (left pumps into it)

What is the covering of the heart called?

pericardium

Functions of the pericardium

-Protects and anchors the heart

-Allows for the heart to work in a relatively friction-free environment

inflammation of the pericardium

Pericarditis

3 layers of the heart wall

1. Epicardium

2. Myocardium

3. Endocardium

Do veins convey blood toward or away from the heart?

To the heart

Do arteries convey blood toward or away from the heart?

Away from the heart

What is the largest artery in the body?

aorta

Epicardium

portion that covers the friction free environment

What chambers is the coronary sulcus between?

between atria (upper chambers) and ventricles (lower chambers)

What chambers are the interventricular sulci between?

between left and right ventricles

interatrial septum

separates the two atria

interventricular septum

separates the right and left ventricles

What is the function of heart valves?

ensure one way flow of blood

Why is the myocardium surrounding the left ventricle is so much thicker than the right ventricle?

Left side needs to pump to all body tissues vs right side only pumping to lungs (closer to heart) There needs more force to pump to other body tissues.

Blood flow of the heart

Why does the blood have coronary circulation?

Myocardium needs its own blood supply

Coronary Heart Disease (CHD)

Areas of partial or complete blockage of coronary circulation, usually due to plaque

What structure of the heart does the coronary circulation dump into?

Right atrium

myocardial infarction

Heart attack occurs due to lack of oxygen to heart tissue (myocardium)

What is a lumen of a blood vessel?

blood-containing space surrounded by tunics (layers)

Tunics of Blood Vessel Walls

tunica intima,

tunica media,

tunica externa

Tunica intima function

forms smooth frictionless layer to allow efficient blood flow

Tunica externa function

protects and reinforces the vessel, and anchors it to surrounding structures.

Tunica media function

Controls dilation and constriction of vessels

What portion of the nervous system controls vasoconstriction/vasodilation?

sympathetic system

What is the function of all the elastic fibers in elastic arteries?

can withstand large blood pressure fluctuations - can expand & recoil.

What is the function of the smooth muscle in the tunica media?

for vasoconstriction and vasodilation

What is the function of capillaries?

site of exchange between blood and tissues

what structure regulates how much blood enters them

precapillary sphincter

What is an edema?

Abnormal accumulation of fluid in interstitial spaces of tissues.