We will begin the warm up after the bell and after we switch seats.

MONDAY 1/4/2016

1. What are some things that you remember about our heart?

2. How many chambers does our heart have? Are all organisms the same?

MONDAY 1/4/2016

1. Draw and label the four parts of the heart. Show the direction of flow of blood.

2. What creates blood pressure?

TUESDAY 1/5/2016

1. What are the different jobs your blood takes on?

2. Why is it that an electrode can measure your heart rate?`

WEDNESDAY 1/6/2016

1. At what point does the oxygen in your blood leave and CO2 enter?

2. What are some things you need to be careful of when taking blood pressure?

THURSDAY 1/7/2016

1. What are two differences between a vein and an artery?

2. How does exercise affect your heart rate and blood pressure?

FRIDAY 1/8/2016

1. What was one new thing you learned during the lab?

2. Why did everyone's blood pressure and heart rate differ both before and after exercise?

MONDAY 1/11/2016

1. Why do you think iron is so important to the blood?

2. What other nutrients are important to your blood and why?

TUESDAY 1/12/2016

WEDNESDAY 1/13/2016

After Watching this short clip. Write a summary of what is happening. Use this to see what you know and still do not understand.

THURSDAY 1/14/2016

1. What are some things that make capillaries so unique or different from other arteries and veins?

2. How are capillaries and alveoli (lungs) similar?

FRIDAY 1/15/2016

1. What part of the poster did you struggle with the most when presenting?

2. What do the SA node and purkinje fibers do for the heart?

MONDAY 1/19/2016

The Cardiovascular System:Major Functions

• Delivers O2, nutrients

• Removes CO2, other waste

• Transports hormones, other molecules• Temperature balance and fluid regulation• Acid-base balance• Immune function

The Cardiovascular System

• Three major circulatory elements1. A pump (heart)2. Channels or tubes (blood vessels)3. A fluid medium (blood)

• Heart generates pressure to drive blood through vessels

The Heart

• Four chambers–Right and left atria (RA, LA): top, receiving

chambers–Right and left ventricles (RV, LV): bottom,

pumping chambers

RA LA

RV LV

Figure 6.1

Blood Flow Through the Heart

• Right heart: pulmonary circulation– Pumps deoxygenated blood from body to lungs– Superior, inferior vena cavae RA tricuspid

valve RV pulmonary valve pulmonary arteries lungs

• Left heart: systemic circulation– Pumps oxygenated blood from lungs to body– Lungs pulmonary veins LA mitral valve

LV aortic valve aorta

Myocardium

• Myocardium: cardiac muscle• LV has most myocardium

– Must pump blood to entire body– Thickest walls – LV hypertrophies with exercise and with disease– But exercise adaptations versus disease adaptations

very different• Only one fiber type (similar to type I)

– High capillary density– High number of mitochondria

Myocardium Versus Skeletal Muscle

• Skeletal muscle cells– Large, long, unbranched, multinucleated– Intermittent, voluntary contractions– Ca2+ released from SR

• Myocardial cells– Small, short, branched, one nucleus– Continuous, involuntary rhythmic contractions– Calcium-induced calcium release

Intrinsic Control of Heart Activity: Cardiac Conduction System

• Spontaneous rhythmicity: special heart cells generate and spread electrical signal– Sinoatrial (SA) node– Atrioventricular (AV) node– Purkinje fibers

• Electrical signal spreads via gap junctions– Intrinsic heart rate (HR): 60 -100 beats/min

Intrinsic Control of Heart Activity: Cardiac Conduction System

• SA node: initiates contraction signal– Pacemaker cells in upper posterior RA wall– Signal spreads from SA node via RA/LA to AV node– Stimulates RA, LA contraction

• AV node: delays, relays signal to ventricles– In RA wall near center of heart– Delay allows RA, LA to contract before RV, LV– Relays signal to AV bundle after delay

Intrinsic Control of Heart Activity: Cardiac Conduction System

• AV bundle: relays signal to RV, LV– Travels along interventricular septum– Divides into right and left bundle branches– Sends signal toward apex of heart

• Purkinje fibers: send signal into RV, LV– Terminal branches of right and left bundle branches– Spread throughout entire ventricle wall– Stimulate RV, LV contraction

1. What are some pieces that are necessary to include in a graph?

2. Explain which sides of the heart carries deoxygenated and oxygenated blood. Where are their destinations?

WEDNESDAY 1/20/2016

Figure 6.5

Extrinsic Control of Heart Activity:Parasympathetic Nervous System

• Reaches heart via vagus nerve• Carries impulses to SA, AV nodes

– Releases ach, hyperpolarizes cells– Decreases HR, force of contraction

• Decreases HR below intrinsic HR– Normal resting HR (RHR): 60 to 100 beats/min– Elite endurance athlete: 35 beats/min

Extrinsic Control of Heart Activity:Sympathetic Nervous System

• Opposite effects of parasympathetic• Carries impulses to SA, AV nodes

– Releases norepinephrine, facilitates depolarization– Increases HR, force of contraction

• Increases HR above intrinsic HR– Determines HR during physical, emotional stress– Maximum possible HR: 250 beats/min

Cardiac Arrhythmias• Bradycardia – slow heart action

• Tachycardia- rapid heart beat

• Premature ventricular contraction – beats too soon, can be in healthy hearts

• Atrial flutter – atria beat too fast

• Ventricular tachycardia – ventricles beat to fast

Cardiac Cycle

• All mechanical and electrical events that occur during one heartbeat

• Diastole: relaxation phase–Chambers fill with blood–Twice as long as systole

• Systole: contraction phase

Electrocardiogram (ECG)

• ECG: recording of heart’s electrical activity– Different electrical views– Diagnostic tool for coronary artery disease

• Three basic phases– P wave: atrial depolarization– QRS complex: ventricular depolarization– T wave: ventricular repolarization

Figure 6.8

Cardiac Cycle: Ventricular Systole

• QRS complex to T wave• 1/3 of cardiac cycle• Contraction begins

– Ventricular pressure rises– (heart sound 1, “lub”)– Blood ejected– At end, blood in ventricle

Cardiac Cycle: Ventricular Diastole

• T wave to next QRS complex• 2/3 of cardiac cycle• Relaxation begins

– Ventricular pressure drops– (heart sound 2, “dub”)– Fill 70% passively, 30% by atrial contraction– At end, blood in ventricle

Stroke Volume, Ejection Fraction

• Stroke volume (SV): volume of blood pumped in one heartbeat– During systole, most (not all) blood ejected– EDV – ESV = SV– 100 mL – 40 mL = 60 mL

• Q = HR x SV– RHR ~70 beats/min, standing SV ~70 mL/beat– 70 beats/min x 70 mL/beat = 4,900 mL/min– Use L/min (4.9 L/min)

The Vascular System

• Arteries: carry blood away from heart

• Capillaries: site of nutrient and waste exchange

• Veins: carry blood from venules back to heart

Blood Pressure

• Systolic pressure (SBP) – Highest pressure in artery (during systole) – Top number, ~110 to 120 mmHg

• Diastolic pressure (DBP)– Lowest pressure in artery (during diastole)– Bottom number, ~70 to 80 mmHg

• Mean arterial pressure (MAP)– Average pressure over entire cardiac cycle– MAP ≈ 2/3 DPB + 1/3 SBP

General Hemodynamics• Blood flow: required by all tissues• Pressure: force that drives flow

– Provided by heart contraction• Resistance: force that opposes flow

– Provided by physical properties of vessels– radius most important factor

• Easiest way to change flow change R– Vasoconstriction (VC)– Vasodilation (VD)– Diverts blood to regions most in need

Distribution of Blood

• Blood flows to where needed most– Often, regions of metabolism blood flow– Other examples: blood flow changes after

eating, in the heat.• At rest (Q = 5 L/min)

– Liver, kidneys receive 50% – Skeletal muscle receives ~20%

• During heavy exercise (Q = 25 L/min)– Exercising muscles receive 80% of Q Flow to

liver, kidneys decreases

Figure 6.14

Integrative Control of Blood Pressure

• Blood pressure maintained by autonomic reflexes

• Baroreceptors– Sensitive to changes in arterial pressure– Afferent signals from baroreceptor to brain– Efferent signals from brain to heart, vessels– Adjust arterial pressure back to normal

Return of Blood to the Heart

• Upright posture makes venous return to heart more difficult

• Three mechanisms assist venous return– One-way venous valves– Muscle pump– Respiratory pump

Figure 6.15• Blood has 3 major

functions– Transportation (O2,

nutrients, waste)– Temperature regulation– Acid-base (pH) balance

• Blood volume: 5 to 6 L in men, 4 to 5 L in women

Blood

• Plasma (55-60% of blood volume)– Can decrease by 10% with dehydration in the heat– Can increase by 10% with training, heat acclimation– 90% water, 7% protein, 3% nutrients

• Formed elements (40-45% of blood volume)– Red blood cells (99%)– White blood cells (<1%)– Platelets (<1%)

Red Blood Cells

• No nucleus, cannot reproduce– Replaced regularly – Life span ~4 months– Produced and destroyed at equal rates

• Hemoglobin– Oxygen-transporting protein in red blood cells

(4 O2/hemoglobin)– Heme (pigment, iron, O2) + globin (protein)– 250 million hemoglobin/red blood cells– Oxygen-carrying capacity: 20 mL O2/100 mL blood