BR – Intro. to the Heart

What are we doing today?

1. Intro Lab – due at the end of the period

HW – Ch. 13 HW #1 due TuesdayCh. 13 HW #2 due Monday 2/24

BR – Label the heart

Turn in HW

What are we doing today?

1. Notes on Cardiovascular System

HW – Heart Dissection - FRIDAYCh. 13 HW #2 due Monday 2/24

Label the Heart

Label the Structures below

Cardiovascular System

Major Functions •Transport O2

•Transport nutrients, hormones

•Transport wastes

Location:

•Within mediastinum of the thoracic cavity (thorax)

• Backbone - posterior

• Sternum - anterior

• Bordered laterally by lungs

• Base below second rib

•Distal end downward to left

• Terminates at the apex that rests of the diaphragm

Paths of Circulation and Vessels

Pulmonary circuit

•RV lungs LA

Systemic circuit

• LV body Vena Cava RA

Blood VesselsArteries

• Carry away from the heart

• 3 layers of tissue

• Aorta - largest

• Arterioles

• Vasoconstriction• contract; diameter reduced

• Vasodilation• relax; diameter increased

Atherosclerosis

• Arterial disease

• Cholesterol is deposited - “plaque”

• Arteriosclerosis

TreatmentAngioplasty

Bypass

“Cabbage” (coronary artery bypass graft)

Blood Vessels

Veins

• Carry blood back to the heart

• Venules

• Contain valves

• 3 layers of tissue but not as thick as arteries - why?

Vessels -Capillaries

• Smallest vessels

• Form connections between arterioles and venules• Capillary beds

• Single simple squamous layer

• Osmosis, diffusion, filtration

• Blood brain barrier

Pericardium

3 layers

• Fibrous - outer layer; attached to diaphragm

• Visceral - inner layer; covers heart

• Parietal - inner lining of the fibrous pericardium

Pericardial cavity

• serous fluid to reduce friction during heart contractions

• pericarditis

Walls of the Heart

3 layers

Epicardium

•protection

Myocardium

•mainly cardiac tissue

•responsible for forcing blood out of the heart

Endocardium

•contains the Purkinje fibers (cardiac impulse fibers)

4 Chambered Heart

Right and Left Atria

• Superior chambers

• Receive blood

Right and Left Ventricles

• Inferior chambers

• Pump blood

Coronary sulcus

• Deep groove separating the atria and ventricles

Interventricular sulci

• Boundary between L and R ventricles

AtriaThin walls

Left atrium

• Receives blood returning from the lungs via pulmonary veins

Right atrium

• Receives blood from superior and inferior vena cava and the coronary sinus

Auricles on top of atria

• Help atria receive more blood

Ventricles• Pumping chambersContains: • Papillary muscles

• contract when the ventricle contracts

• Chordae tendinae• attach to valves to keep them from swinging back into the

atria

Septum• separates right chambers from the left

chambers• Septal defectsForce blood into arteries• right ventricle pulmonary arteries lungs• left ventricle aorta to go to the body•why is the left ventricle thicker?

BR – Label the heart

What are we doing today?

1. Finish Anatomical notes on Cardiovascular System

2. Begin lab work

HW – Heart Dissection - FRIDAYCh. 13 HW #2 due Monday 2/24

Label the Heart

ValvesPrevent back flow of blood

Atrioventricular valves:

• Tricuspid valve• between r. atria & r. ventricle

• Bicuspid (mitral) valve • between l. atria & l. ventricle

Pulmonary semilunar valve

• between r. ventricle & pulmonary artery

Aortic semilunar valve

• between the l. ventricle & aorta

Mitral Valve Prolapse and Endocarditis

•Affects up to 6% of the population• chest pain, palpitations,

fatigue, anxiety

• Bicuspid valves stretch and bulge into the left atrium

• Susceptible to endocarditis

Coronary Vessels

First 2 branches off of the aorta•Coronary arteries that supply

myocardium with blood•Myocardium contains MANY

capillaries•Myocardium drained by coronary

veins•Veins empty into coronary sinus• returns the blood to the right

atria

Coronary Artery Disorders/DiseasesAngina pectoris• blockage of coronary artery by a

thrombus/embolus• Chest pain – indication that an issue is present

Myocardial infarction (heart attack)• coronary thrombosis

(artery is completely blocked)

• part of the heart muscle is killed and replaced by connective tissue (scars)

HW Check - Labeling

• Verse 1:

• Pump, pump, pumps your blood.

• The right atrium’s where the process begins,

• where the CO2 blood enters the heart.

• Through the tricuspid valve, to the right ventricle, the pulmonary artery, and lungs.

• Once inside the lungs, it dumps its carbon dioxide and picks up its oxygen supply.

• Then it’s back to the heart through the pulmonary vein, through the atrium and left ventricle.

• Pump, pump, pumps your blood.

• Pump, pump, pumps your blood.

• Verse 2:

• The aortic valve’s, where the blood leaves the heart,

• then it's channeled to the rest of the body.

• The arteries, arterioles, and capillaries too

• bring the oxygenated blood to the cells.

• The tissues and the cells trade off waste and CO2,

• which is carried through the venules and the veins.

• Through the larger vena cava to the atrium and lungs,

• and we're back to where we started in the heart.

https://www.youtube.

com/watch?v=P_d0y

kpzQgY

Pathway of Blood

Lab Work

1. Complete the lab pgs. 1-5

2. Work on heart dissection paperwork –dissection on Friday

BR – Pick up Heart Dissection Intro. video

What are we doing today?

1. Lab work• Pgs. 1-5 by end of period Friday• Heart dissected by end of period Friday

HW – Ch 12 HW #2 due Monday

BR – Heart Labeling

What are we doing today?

1. Lab work• Pgs. 1-5 – turn in before leaving• Heart dissected by end of period Friday

• Turn in dissection paper if finished OR finish as HW and turn in Monday

HW – Ch 12 HW #2 due Monday

Label the Structures below

SVC

IVC

RA

tricuspid

RV

Pulmonary semilunar valve

Pulmonary artery

LA

bicuspid

LV

Aortic semilunar valve

Aorta

BR – Circulation pathways

Turn in HW

What are we doing today?

1. Finish notes2. Lab work – lab due beginning of class on Wednesday

HW – Crossword

Lab Practical – Oral ID and paper functionsQuest – Friday (bonus quizizz (2) by 7:30 am)

Contractile Cells in Cardiac Tissue – Action PotentialVentricular contractile cell

• AP begins when plasma membrane is at threshold from receiving the stimulus from an adjacent cell

1. Rapid depolarization

• Sodium channels open; membrane depolarizes

• Close at 30 mV

2. Plateau

• Sodium actively pumped out

• Calcium ion channels open for a relatively long period

• Delay repolarization and initiate contraction

3. Repolarization

• Calcium channels begin to close

• Potassium channels open and exit the cell

Cardiac Cycle• Series of events that

constitute a heartbeat

• Pressure dependent (rise and fall of pressure between chambers)

• 70% (flows naturally) - 30% (needs to be pumped)

• .8 seconds for one cycle to be completed

Heart SoundsSpeed of blood flow creates vibrations

Lub-dub

• Monosyllables describing the heart’s sounds

• lub = ventricular contraction; bicuspid & tricuspid valves (atrioventricular valves) closing

• dub = ventricular relaxation/atrial contraction; pulmonary & aortic (semilunar) valves closing

Murmur

• Abnormal sounds that indicate a problem with the valves

Cardiac Conduction SystemSinoatrial Node (pacemaker)• Responsible for the rhythmic contractions• R. Atrium near the superior vena cava• No nervous system connection• cells excite themselves in a rhythm• initiate impulses 70-80 times/min.SA node - AV node - purkinje fibersHeart Block• When the AV node partially releases the

ventricles from the control of the SA nodeHeartbeat Regulation

Hypothalamus

• emotional responses

Parasympathetic and Sympathetic nervous systems

Receptors in vessels send messages to cardiac center in the medulla

Norepinephrine

• increases contractions

Acetylcholine

• decreases contractions

Electrocardiogram

P wave = first wave

• Depolarization of the atria

QRS

• Ventricles are depolarizing prior to contraction

T wave = second wave

• Repolarization of the ventricles

• Diastole

• One cardiac cycle

Abnormal EKG’STachycardia - >100 beats/min

Bradycardia - <60 beats/min

Flutter - rapid; 250-350 beats/min.

Fibrillation - rapid; uncoordinated; heart becomes useless as a pump

• ventricular usually causes death

Blood Pressure• Pressure exerted by blood against

inner walls of vessels

• Responds to cardiac cycle pattern

• Systolic - top #

• Diastolic - bottom #

• Pulse• expanding & recoiling of the

arteries

Blood PressureDirectly related to volume of blood

• what happens to when blood is lost?

Stroke volume

• ~ 70ml discharged

Blood volume

• sum of blood cell + plasma

Hypertension

• persistent elevated bp

Factors affecting bp

• Diameter of arteriole (increase)

• Blood viscosity (increase)

• Pulse rate (increase)

• Urine output (decrease)

• Sudden change in position (decrease)

• Exercise (increase)

• Physical training (decrease)

• Chemicals (stimulants increase; depressants decrease)

• Blood loss (decrease)

• Arteriosclerosis (increase)

BR – Cardiac Cycle events

What are we doing today?

1. Finish Lab2. Begin reviewing for

quest and practical

HW – crossword (period 4)

SA node generates an impulse

Impulse has a 0.1 second pause at the AV node

AV bundles connects the atria to the ventricles

Bundle branches conduct impulse through septum

Impulse travels to purkinjefibers; fibers depolarize the contractile cells in the papillary muscles and ventricles contract

BR – Label heart

Turn in Lab

What are we doing today?

1. Kahoot2. Review with partner(s) for practical

HW – Partner practical tomorrow (100 pts)Quest Friday (100 pts)