The Circulatory SystemThe Circulatory System

Part 2Part 2

Blood, Lymph and ETCBlood, Lymph and ETC

Composition Composition of Bloodof Blood

Blood will Blood will separate into separate into two parts:two parts:

a.a. 55% 55% plasma (liquid)

b. 45% blood cells (solid) (called Formed elements)

list the major list the major components of components of

plasma plasma

Mostly water (92%) with MANY different dissolved substances:

a. Nutrients – glucose, amino acids, vitamins, minerals

b. CO2,O2

c. Blood proteins: i. Antibodiesii. hormones iii. clot-forming proteins. (fibrinogen)iv. Albumin (transports

bilirubin)v. Globulins (the protein

in lipoproteins)d. Salts: Na+, Ca+, K+, Mg+

e. wastes: urea

i. i. Antibodies -part of the immune system -part of the immune system

- help fight infections.- help fight infections.

antibodies - tag the foreigners for

the killer cells Killer Cells

Foreigner

ii. ii. HormoneHormone

ss Chemical Chemical messengermessengers sent from s sent from brain to tell brain to tell cells or cells or organs organs what to do; what to do; travel via travel via bloodblood

iii. Clot-Forming Proteins- iii. Clot-Forming Proteins- FibrinogenFibrinogen

Work with platelets to Work with platelets to form a thrombus form a thrombus (scab)(scab)

describe the describe the shape, shape,

function, and function, and origin of red origin of red blood cells, blood cells, white blood white blood cells, and cells, and

plateletsplatelets A. Red Blood CellsA. Red Blood Cells B. White Blood B. White Blood

CellsCells C. PlateletsC. Platelets

Red Blood CellsRed Blood Cells Aka. ErythrocytesAka. Erythrocytes Source = stem cellSource = stem cell Disc-shapedDisc-shaped Hemoglobin has Hemoglobin has

iron in it (makes iron in it (makes your blood red!)your blood red!)

Delivers gases to Delivers gases to and from cellsand from cells

White Blood White Blood CellsCells Aka. LeukocyteAka. Leukocyte

Source = stem cellsSource = stem cells Larger than RBCLarger than RBC Work together with Work together with

antibodies to fight antibodies to fight infectionsinfections

PlateletsPlatelets

Aka. ThrombocyteAka. Thrombocyte Source = stem cellSource = stem cell Fragment of larger cellsFragment of larger cells Clots blood(scab)Clots blood(scab)

Blood Clot

Blood Cell Formation Blood Cell Formation DiagramDiagram

ReviewReview Plasma: Water, Plasma: Water,

nutrients, COnutrients, CO22, , antibodies, antibodies, hormones, clot-hormones, clot-forming proteinsforming proteins

Blood Cells: Blood Cells: RBC’s, WBC’s and RBC’s, WBC’s and PlateletsPlatelets

describe capillary-tissue describe capillary-tissue fluid exchangefluid exchange

Determined by two Determined by two forces: forces:

1.1. Blood Pressure Blood Pressure

2.2. Osmotic Pressure Osmotic Pressure (the pressure that (the pressure that water feels to water feels to move according to move according to the concentration the concentration gradient between gradient between the tissues and the the tissues and the bloodbloodosmotic vs hydrostatic pressure animation

Moving Moving through the through the

CapillaryCapillary

At the arteriole At the arteriole end of the end of the capillary: capillary:

B.P. B.P. = 40mmHg= 40mmHg O.P.O.P. = 25mmHg= 25mmHg Net Net = 15mmHg= 15mmHg

Since BP exceeds Since BP exceeds OP, water, aa’s, OP, water, aa’s, and oxygen leave and oxygen leave the capillary the capillary because they are because they are forced (squeezed) forced (squeezed) out of the blood out of the blood and into the cells. and into the cells.

Blood cells and Blood cells and proteins are too proteins are too large – they stay in large – they stay in the bloodthe blood

Middle of Middle of CapillaryCapillary

BPBP = = 25mmHg25mmHg

OPOP = = 25mmHg25mmHg

NetNet = 0 = 0 mmHgmmHg

BP and OP are BP and OP are about equal in the about equal in the middle of the middle of the capillary so capillary so diffusion causes diffusion causes the nutrients to the nutrients to leave the blood leave the blood and enter the cells and enter the cells (following their (following their concentration concentration gradient)gradient)

Wastes will diffuse Wastes will diffuse out of the cells out of the cells and into the blood and into the blood at this point as at this point as well.well.

Venule End of the Venule End of the CapillaryCapillary

BPBP = 10mmHg= 10mmHg OP = 25mmHgOP = 25mmHg NetNet = 15mmHg = 15mmHg

(in the opposite (in the opposite direction!)direction!)

Now OP is greater than BP, Now OP is greater than BP, so water will move from so water will move from the tissues and into the the tissues and into the blood. blood.

Urea and carbon dioxide Urea and carbon dioxide are also carried with the are also carried with the waterwater

Lymph SystemLymph System

Lymphatic SystemLymphatic System

3 main functions:1.transport of excess tissue fluid back to cardiovascular system2.absorption of fat from the intestine and transport to blood3.fighting infection by distributing germ-fighting white blood cells= lymphocytes

identify and give functions identify and give functions of lymph capillaries, veins, of lymph capillaries, veins,

and nodes and nodes

considered part of the circulatory system since it contains lymph, a moving fluid that comes from the blood and returns to the blood by way of the lymphatic vessels.

The lymphatic system is thus a secondary transport system. Lymph has no pump of its own. Its flow depends on pressure from the blood system, the massaging effect of the muscles and the one-way-valves in it’s vessels.

1. Excess fluid1. Excess fluid More water is

forced out of the capillary at the arteriole end then re-enters at the venule end.

The LYMPHATIC system vessels collect the extra water and return it to the blood at the duct connected to the subclavian vein

  

interstitial fluid, the lymph picks up particles too big to be absorbed through capillary, include: cell debris, fat globules, and tiny protein particles

lymph is filtered by the numerous white blood cells

fluid re-enters the blood through the subclavian vein.

2. Absorbs Fat

3. Fighting Infection 3. Fighting Infection The lymphatic system also distributes

germ-fighting white blood cells. Lymph resembles plasma It is formed from bits of blood and

other body liquids, called interstitial fluid that collect in the spaces between cells.

Lymph OrgansLymph Organs Lymph nodes – round

structures located along lymph vessels (beneath armpits, base of jaw, groin ) Filters lymph Produce lymphocytes

(WBC) which produce antibodies

Other lymph organs include tonsils, spleen, thymus gland

Blood and Body Blood and Body TemperatureTemperature

Your blood vessels Your blood vessels help control your help control your body temperature by body temperature by sending extra blood sending extra blood to your skin if you to your skin if you are hot OR by are hot OR by keeping extra blood keeping extra blood AWAY from your skin AWAY from your skin to keep you warmto keep you warm

The capillaries The capillaries DILATE or DILATE or CONTRACTCONTRACT to control to control the blood flowthe blood flow

Open heart surgeryOpen heart surgery

Regulation of Blood Regulation of Blood Pressure occurs by Four Pressure occurs by Four

Mechanisms:Mechanisms:1. 1. Altering Heart RateAltering Heart Rate2. 2. Altering Contactility Altering Contactility

(how hard it pumps)(how hard it pumps)3. 3. Altering Blood Vessel Altering Blood Vessel

Diameter Diameter (vasoconstriction or (vasoconstriction or vasodilatation)vasodilatation)

4. 4. Altering Blood Altering Blood Volume Volume (kidneys (kidneys either re-absorb extra either re-absorb extra HH22O or expel extra O or expel extra HH22O)O)

The Cardiovascular CentreThe Cardiovascular Centre in the Brain (a in the Brain (a group of neurons scattered within the medulla)group of neurons scattered within the medulla)

- will regulate the heart rate using all of these - will regulate the heart rate using all of these mechanisms to varying degrees causing either mechanisms to varying degrees causing either an increase or decrease in BP.an increase or decrease in BP.

  HypertensionHypertension = high blood pressure (over 120/80) = high blood pressure (over 120/80)

HypotensionHypotension = low blood pressure (under 120/80) = low blood pressure (under 120/80)

Keeping your Circulatory Keeping your Circulatory System HealthySystem Healthy

Eat a healthy Eat a healthy diet (try to keep diet (try to keep the saturated the saturated fats and fats and cholesterol, and cholesterol, and salt levels low)salt levels low)

Get lots of sleep Get lots of sleep and exerciseand exercise

Don’t smokeDon’t smoke Drink lots of Drink lots of

waterwater

Heart RateHeart Rate Average resting heartAverage resting heart

rate is 60-80 beats per rate is 60-80 beats per minute (bpm)minute (bpm)

The heart is a muscle – The heart is a muscle – exercise makes it exercise makes it strongerstronger

A highly conditioned A highly conditioned aerobic athlete (ex. aerobic athlete (ex. Long distance runner) Long distance runner) will have a resting heart will have a resting heart rate of 28-40 bpm.rate of 28-40 bpm.

When exercising, a good When exercising, a good target range for heart target range for heart rate in teens is between rate in teens is between 150-190 bpm150-190 bpm

High Blood High Blood PressurePressure

BP is higher than normal BP is higher than normal all of the timeall of the time

Puts Puts extra strain extra strain on the on the heartheart

Can cause Can cause capillaries to capillaries to burstburst damaging heart, damaging heart, brain or kidney tissuebrain or kidney tissue

Is the leading cause of Is the leading cause of heart failureheart failure

Too much salt in the diet Too much salt in the diet can cause HBP, as can can cause HBP, as can excessive, long term excessive, long term stressstress

Some Factors that can Some Factors that can affect BPaffect BP::

ExerciseExercise:: raises BP during exercise, but raises BP during exercise, but decreases BP after because the heart is decreases BP after because the heart is stronger.stronger.

Sodium intakeSodium intake: Increases Blood Volume which : Increases Blood Volume which increases BPincreases BP

CaCa++++ and K and K++ intake intake: Decreases BP: Decreases BP Alcohol ConsumptionAlcohol Consumption: Increases BP because in : Increases BP because in

increases the acidity of the blood, which increases the acidity of the blood, which stimulates the CV centre to increase BPstimulates the CV centre to increase BP

Some more Factors that Some more Factors that can affect BPcan affect BP::

Body WeightBody Weight: Being overweight puts : Being overweight puts extra strain on the heart: increases BPextra strain on the heart: increases BP

SmokingSmoking: increases BP: increases BP StressStress: The autonomic NS thinks that : The autonomic NS thinks that

you must prepare for a fight, therefore you must prepare for a fight, therefore increasing the BPincreasing the BP

AtherosclerosisAtherosclerosis: Decreases the : Decreases the diameter of vessels - therefore diameter of vessels - therefore increasing BPincreasing BP

ETC.!!ETC.!!

Cardiovascular Cardiovascular Centre Centre

The CV centre receives sensory input from many different sources:

1. Higher brain centers (telling you to prepare for something)

2. Baroreceptors - monitoring blood pressure by using stretch receptors in the blood vessels

3. Chemoreceptors - monitoring O2 , CO2, and H+ concentrations in the blood