PSIO 107 Exam 4

What color is Blood

Hemoglobin (red)- iron

Vanabin (yellow)- vanadium

cholorocruorin (green)

Hemocyanin (blue)- copper

Hemerythrin (purple) - no heme component

Functions of blood

* carry oxygen and carbon dioxide
* provide capability of defense by carrying immune cells and antimicrobial chemicals
* carry blood clotting cells and substances
* carry nutrients and wastes

composition of blood

formed elements

* erythrocytes (red blood cells)
* Leukocytes (white blood cells)
* thrombocytes (platelets)

plasma

Erythrocytes

RBCs

contain hemoglobin

* binds oxygen (and CO2)
* each hemoglobin can carry 4 oxygen molecules
* approximately 250,000 hemoglobin molecules per RBC

Mature RBCs do not have a nucleus

maximizes oxygen-carrying capability

sacrifices ability to repair self

* life span \~ 120 days

RBC concentration stays constant

RBCs are replaced from red bone marrow by demand

* process of erythropoiesis

Red Blood Cell Pathologies: Too few RBCs

Anemia

* nutritional problems
* sickle cell anemia
* kidney problems
* blood loss
* iatrogenic issue

Too many RBCs

Polycythemia

* tumor-causing overproduction
* respiratory disease compensation
* performance-enhancing practice

Leukocytes

WBCs

Granulocytes

* basophils
* produce heparin and histamine
* Neutrophils
* phagocytes
* Eosinophils
* respond to parasites or allergens

Agranulocytes

* monocytes
* turn into macrophages when activated
* lymphocytes
* T-cells and B-cells
* Control immunity

Leukocyte Functions

* vital for immune response to pathogens and host defenses
* neutrophil engulfing bacterium (very cool)

Platelets

* originate from megakaryocytes
* mediate part of the clotting process

Hemostasis consists of three parts

Vascular spasm, platelet plug formation, coagulation

vascular spasm

serotonin induced vasoconstriction

Platelet plug formation

* sticky platelets attach to exposed collagen
* net of platelets contract to reduce size of gap

Coagulation

* “clotting cascade”- inactive substances are activated to induce the formation of the clot
* positive feedback cycle which culminates in cessation of leaking blood
* final step of cascade is fibrinogen converted to fibrin

inappropriate clotting

* plaque formation can activate platelets
* blood pooled in varicose veins can coagulate
* thrombus formation → embolus

too little clotting

* hemophilia
* hereditary (genetic link) - lack of clotting factor
* multiple sub-types

Hematopoiesis

blood cells form from stem cell pop. in red bone marrow

* also, yolk sac, liver and spleen during development

RBC formation stimulated by erythropoietin

WBC and platelet formation due to similar factors

Plasma

92% water

remaining composition is:

* plasma proteins (albumin, globulins, clotting factors, fibrinogen)
* electrolytes (0.9% NaCl, K, Ca, phosphate, and others)
* nutrients (carbs, lipids, amino acids, vitamins)
* metabolic wastes (urea, ketoacids, bilirubin)
* respiratory gases (O2, CO2)
* hormones

plasma without clotting is called serum

\*coconut blood can serve as a substitute, FOR PLASMA

ABO system

Type A, B, AB, O

Type A

has A anitgen, B antibody

Type B

has B antigen, A antibody

Type AB

has both A and B antigens ( no antibodies)

Type O

has both A and B antibodies (no antigens)

Rh factor

* Also called D antigen, identified from Rhesus Monkey blood
* Rh+ blood contains the Rh-antigen
* Rh- blood does not contain the antigen
* NOTE: must be exposed to Rh antigen before producing an anti-Rh antibody
* this becomes relevant for pregnant patients and their developing fetuses
* Common nomenclature: ABO type followed by Rh factor status
* Ex: O-, A+, etc.

Blood transfusion reactions

agglutination will occur if incompatible blood types are mixed

Someone with Type A blood cannot receive type B blood transfusion. What component int the type A blood makes it so that they can’t receive a type B blood infusion?

Anti-B antibody; because if we anti-B antibody in the Type A blood, the B antigens in Type B blood would cause agglutination, causing improper clotting.

Which blood is the best donor blood

Type O, but Type O recipients can only receive Type O blood

Which blood type is least picky or can accept both Type A or Type B

AB, just dont give an AB type O blood

CV system

* heart
* dual-sided, 4-chamber pump
* Arteries and veins
* conduction vessels (conduits)
* Arterioles and venules
* resistance vessels (regulate blood flow)
* Capillaries
* Nutrient exchangers with high-surface area
* Closed circuit w/ 2 “sides”
* pulmonary loop
* systemic loop

Heart overview

Sits in mediastinum of thoracic cavity

4 chambers

* 2 atria
* 2 ventricles

4 major vessels

* Vena cava, pulmonary artery, pulmonary vein, Aorta

Coronary circulation (supplies cardiac cells)

heart wall is layered

* epicardium, myocardium, endocardium

Pericardium

double-walled serous membrane surrounding the heart

* visceral pericardium
* parietal pericardium

anchors and suspends heart

* shock-absorption and freedom of movement

provides lubrication during movement

Pericardial fluid

fills the “potential space” inbetween visceral and parietal pericardium

* can become pathologic if fluid builds up → becomes pericardial effusion

Coronary Circulation

* right coronary artery
* \~25% of heart tissues
* left coronary artery
* \~75% of heart tissues
* some exceptions because not all hearts have the same coronary artery dominant pattern

Major blood vessels associated with the Heart

1. superior/inferior Vena Cava
2. Pulmonary Trunk
3. Pulmonary Veins
4. Aorta

Superior/inferior Vena Cava

venous return (of deO2 blood) from systemic circulation

Pulmonary Trunk

deO2 blood to lung circulation

Pulmonary Veins

O2 blood from lung circulation

Aorta

O2 blood to systemic circulation

Internal anatomy of heart

4 Heart Chambers

* right atrium and ventricle
* left atrium and ventricle

4 valves

* right and left atrioventricular valves
* tricuspid and mitral valves
* right and left semilunar valves
* pulmonic and aortic valves

Heart valves

function as one-way doors to prevent backwards blood flow

* Open/close determined by pressure gradient of blood in vessels and heart chambers

Pacemakers

set rate of heartbeat

* Sinoatrial node (SA node) (75 bpm; sets the pace normally, since its the fastest)
* atrioventricular node (40 bpm)
* purkinje fibers (25 bpm)

pattern of impulse is dependent on where the impulse is started

Conduction pathway

SA node → atrial syncytium → AV node → Bundle of His → Left/Right bundle branches → Purkinje Fibers

* SA node depolarizes atrium
* Bundle of His depolarizes ventricular septum
* Purkinje Fibers depolarizes ventricular free walls

Electrocardiograms

Aka EKG or ECG

* no-invasive, diagnostic meas. of the electrical activity of the heart

What do EKGs determine:

* cardiac metrics (P-R interval, R-R interval, etc) and orientation of heart
* Extent/location of ischemic damage
* effect of pharmaceuticals or other drugs and electrolyte disturbances

Which of these heart electrical components

signals frst in the the normal cardiac cycle?

Sinoatrial (SA) node

The sinoatrial (SA) node normally sets the pace

of the heartrate around which value?

75 bpm

Wiggers Diagram

a visual representation of the events throughout a complete heartbeat sequence (cardiac cycle)

Cardiac Cycle

each half of the heart ejects the same amount of blood

Cardiac cycle stage 1

atrial systole: atria contract, AV valves open, semilunar valves closed

Cardiac cycle stage 2

Early Ventricular Systole: atria relax, ventricles contract AV valves forced closed, semilunar valves still closed

Cardiac cycle stage 3

Late Ventricular Systole: atria relax, ventricles contract, AV valves remain closed, semilunar valves forced open

Cardiac cycle stage 4

Early Ventricular Diastole: atria and ventricles relax, AV valves and semilunar valves closed, atria begin passively filling with blood

Cardiac cycle stage 5

Late Ventricular Diastole: atria and ventricles relax, atria passively fill with blood as AV valves open, semilunar valves closed

Which of these sets of valves opens as the

ventricles begin to contract in the the normal

cardiac cycle?

aortic and pulmonic valves

Cardiac output (mL/min) =

HR (bpm) X Stroke volume (mL/beat)

* 5040mL = 72 bpm X 70 mL/beat)

Stroke volume is a function of venous return and cardiac contractility

* \~70mL per beat average
* Altered through muscular pumping, venous return
* sympathetic nerves increase this too

Frank - Starling Law of the Heart

* the normal heart will pump out most of the volume that is returned to it, including increases
* increased venous return → increase stroke volume

Low BP

Sympathetic input → increased heart rate and contractility

Sympathetic effects SA node and motor neurons

High BP

Parasympathetic output → reduced heart rate

A person stands up quickly and feels dizzy for a few

seconds before steadying. Knowing that the

autonomic nervous system helps maintain BP, what

type of response did this standing trigger?

sympathetic

Cardiac output is infuenced by stroke volume. Which

of the following factors/actvites increases stroke

volume?

* leg muscles pumping while walking
* adrenaline rush from seeing a bear on a hike

Blood vessels

arteries

aorta branches into 3 parts

* Right side: Brachiocephalic Artery
* right common carotid artery
* Left common carotid artery
* subclavian artery

veins

know portal circulation?

Fetal circulation

Contains shunts which redirect blood to systemic circulation

* foramen ovale
* ductus arteriosus

Which of the following structures have one-

way valves?

veins

In the fetal circulaton, which has the highest

oxygen concentraton in the blood it contains?

umbilical vein

Describe the layered appearance, from top to bottom, of a tube of blood that has been centrifuged to obtain a hematocrit.

Plasma, buffy coat, red blood cells

Mature erythrocytes do not have a nucleus.

true

An individual may have an infection is his buffy coat is thicker than normal.

TRUE

Which fluid associated with blood does not contain clotting factors?

Serum

An embolism is

a thrombus that has gotten loose and become stuck in the vasculature

The condition whereby there are too many erythrocytes (RBCs) is

polycythemia

Which of the white blood cells are the phagocytic cell largely responsible for removing debris?

neutrophils

The end event of the clotting cascade and subsequent formation of a blood clot is the conversion of

fibrinogen to fibrin

Mothers who have type A- blood that are pregnant with their second type A+ child will have to worry about erythroblastosis fetalis (Rh antibody reaction with Rh antigen).

TRUE

The cells that are responsible for cell- and antibody-mediated immunity are

lymphocytes

Platelets are best defined as

cytoplasmic fragments of cells

Which of the white blood cells are important with parasitic infection?

eosinophils

Which step in hemolysis is caused by the release of serotonin from vascular wall cells?

vascular spasm

Which of the white blood cells are important in the specific defense mechanisms (immunity)?

lymphocytes

What characteristic is shared by eosinophils and basophils?

they are granulocytes

Which hematocrit value would likely be seen with anemia?

35%

Which of the following is an example of a specific body defense mechanism?

immunity

When the heart contracts, into what type of vessel is blood pumped first?

arteries

Heart valves open because of specialized valve muscles that pull them open.

false

A normal heart is governed only by its pacemakers and not by nervous or endocrine input.

false

Which blood vessels serve as the "body's resistance vessels"?

arterioles

Which of the following would enhance blood return to the heart?

skeletal muscles pumping

Which heart chamber receives blood from the peripheral circulation?

right atrium

Arteries have thicker walls than veins.

TRUE

Which heart chamber sends blood to the peripheral circulation?

Left ventricle

In which part of the vasculature does nutrient and waste exchange occur with the body's tissues?

capillaries

Depolarization of a cardiac muscle cell is similar to skeletal muscles with the exception of the movement of which ion across the membrane to lengthen the duration of the action potential?

Calcium

Identify the type of vessel that sits between two capillary beds, such as between the intestines and liver capillaries.

portal vein

The blood pressure in the systemic arteries is greatest during

ventricular systole

Metabolically active tissues have more extensive capillary networks.

TRUE