(Exam 3) Pt. 1 Cardiovascular System: Structure & Function

The cardiovascular system:

1) [...] - nutrients, O2, CO2, enzymes, hormones, ions, metabolic wastes, leukocytes

2) [....]of body temperature

Transports and Stabilization

Works with the [....] system

• Cardiopulmonary or cardiorespiratory system

pulmonary

Two major adjustments of blood flow during exercise:

• Increased [....]

• [...] of blood flow from inactive organs to active muscle

cardiac output and Redistribution

[....]:

- releases pump

- creates pressure to pump blood

Heart

[....]:

- carry blood away from the heart

- Arteries and Arterioles

[....]:

- exchange of O2, CO2, and nutrients with tissues

Capillaries

[....]:

- carry blood toward the heart

Veins and venules

The heart:

- beats [....]

- pumps ~ 1.5 million gallons of blood per year

- [....]

- 4 chambers - 2 [...] and 2 [....]

- Pumps blood into 2 circuits:

[...]

- 100,000 times per day (~70 beats/min);

- 5 - 30 liters per minute

- atria and ventricles

- pulmonary circuit and systemic circuit.

Pulmonary circuits:

o [....] side of the heart

o Pumps [....] blood to the lungs via pulmonary artery

o Returns [....] blood to the left side of the heart via pulmonary veins

Right; deoxygenated; oxygenated

Systemic circuit:

o [...] side of the heart

o Pumps [....] blood to the whole body via [...]

o Returns [...]blood to the [....]side of the heart via veins

Left; oxygenated; arteries; deoxygenated; right

The pericardium:

- The heart is near the [....] chest wall and directly posterior to the sternum in the pericardial cavity

- Pericardium is the serous membrane lining the [....] cavity

- forms 2 layers:

[....]

- also called the epicardium

[....]

- reinforced by a layer called the fibrous pericardium (external sac)

- Between the visceral and parietal is the [....] there is fluid that act as lubricated that reduces against the two layers to help the heart contract.

anterior; pericardial; Visceral and parietal pericardium; pericardial cavity

The myocardium:

- Receives blood supply via [....]

-- high demand for [...]

- [....]

-- Blockage in coronary blood flow results in cell damage/ death

coronary arteries; oxygen and nutrients; Myocardial infarction (MI)

- heart attack is damaged to the myocardium.

Exercise training protects the heart:

- Regular exercise is [....]

-- Reduces incidence of [....]

-- improves survival from a heart attack

- Exercise reduces the amount of [....] from heart attack

-- improvement in heart's [...] capacity.

cardioprotective; heart attacks; myocardial damage; antioxidant

How does cardiac muscle communicate with cardiac muscles?

- The desmosomes connects the membrane of two adjacent cardiac cells

- the gap junction communication allows passage of small ions to generate cardiac muscle cells.

[....]

- Originate at the base of the ascending aorta

o Supply the cardiac muscle tissue

Coronary arteries

The Cardiac Cycle:

- Alternate periods of contraction & relaxation

- [....]:

o Describe the blood being ejected into the ventricles

o Blood is ejected into the ventricles

o Blood is ejected into the pulmonary trunk and the ascending aorta

- [....]:

o Describes relaxation of heart

o Chambers are filling with blood.

Systole; diastole

Step 1 of cardiac cycle:

- Both atrial contract and send blood to the ventricles.

Step 2 of cardiac cycle:

- Aortic valve will only open if the pressure in the ventricles exceeds the pressure in the aorta. This is called isometric volume.

Step 3 of cardiac cycle:

- Ventricular systoles and ventricular diastoles both have 2 phases.

Step 4 of cardiac cycle:

- Ventricular systole first phase: ventricular contraction pushes the AV valve closed but does not create enough pressure to open the semilunar valve.

Step 5 of cardiac:

- The second phase is ventricular pressure rises and exceeds the pressure in the arteries; the semilunar valves open and blood is ejected.

- FINISH THE CYCLE

Arterial blood pressure:

- Expressed as systolic/diastolic

o [...]

- Systolic pressure

o Pressure generated during [...]

- Diastolic pressure

o Pressure in the arteries during [....]

- Pulse pressure

o [....] between systolic and diastolic

- Mean arterial pressure (MAP)

o Average pressure in the [...]

Normal is 120/80 mmHg; ventricular contraction; cardiac relaxation; Difference; arteries

Hypertension:

- Blood pressure above[....] (hypertension)

o Cause unknown [...]

- [....] hypertension

o Result of some other disease process

- Risk factor for:

o Atherosclerosis and heart attack

o Kidney damage

o [...]

130/80 mmHg; (multifactorial); Secondary; Stroke

Factors that influence arterial blood pressure: [...]

Determinants of mean arterial pressure (MAP), Short term regulation, and long term regulation

Determinants of mean arterial pressure (MAP):

• [....]

• Total [...]

- MAP = [....]

- Diameter of the vesicle plays a huge part because if we decrease the diameter, we will have an increase in blood flow because there is not a lot of space.

Cardiac output; vascular resistance; cardiac output × total vascular resistance

Short term regulation:

o [....] nervous system

o Baroreceptors in [....]

§ Increase in BP = [...] SNS activity

§ Decrease in BP = [....] SNS activity

Sympathetic; aorta and carotid arteries (pressure receptors); decreased; increased

Long term regulation:

- [....]

§ Via control of [....]

- kidney; blood volume

Electrical activity of the heart:

- The cardiac cycle is coordinated by conducting cells: [...]

Nodal cells and conducing fiber

Nodal Cells:

- [....] (pacemaker of the heart)

· Establish the rate of contractions

- [....]

- Has pacemaker cells and creates electrical impulses sent to [....] nodes; the atrium will then contract and then a little delay when signals reaches AV node; this happens because we allow [....] to fill with blood; from AV node the impulses travels down to left and right bundle branch and then go to the [....].

Sinoatrial (SA) node; Atrioventricular (AV) node

-AV; ventricular; Purkinje fibers

Conducting fibers:

[....]

- Distribute the contractile stimulus to the myocardium

Electrocardiogram:

- Records the heart's activity

o [...]

§ Atrial depolarization

§ Atrial systole

o [....]

§ Ventricular depolarization and atrial repolarization

§ Atrial repolarization is concealed by the QRS complex.

o [...]

§ Ventricular repolarization

o ECG abnormalities may indicate [....]

§ ST- segment depression can indicate myocardial ischemia

P wave; QRS complex; T wave; coronary heart disease

Diagnostic use of the ECG during exercise:

- Graded exercise test to evaluate cardiac function

o Observe ECG during exercise

o Also observe changes in [....]

- [...]

o Fatty plaque that narrows coronary arteries

o Reduce blood flow to myocardium

§ Myocardial ischemia

- S-T segment depression

o Suggest [....]

blood pressure; Atherosclerosis; myocardial ischemia