Conduction system and BP terms

Question 1

Conductivity

Answer 1

Ability of cells to conduct electrical impulses

Question 2

Excitability

Answer 2

Ability of cells to respond to electrical impulses

Question 3

Automaticity

Answer 3

Ability to generate impulse to contract without external nerve stimulus

Question 4

Sinotrial (SA) Node

Answer 4

Where impulses originate
High in right atrium
Typically 60-100

Question 5

Atroventricular (AV) node

Answer 5

SA impulses arrive at this node
In the right atrium adjacent to septum
Impulses are delayed to fill
Initiate impulses 40-60 if SA node fails

Question 6

Bundle of His

Answer 6

Bundle branches right and left
Purkinje netwrok of fibers causing ventricular contraction
Ventricles can initiate 20-40 BPM (does not meet cardiac need)

Question 7

Depolarization

Answer 7

Increase in electrical change through the exchange of ions across the cell membrane
- Generate cardiac contraction

Question 8

Repolarization

Answer 8

Ventricular recovery in which ions return to the cell membrane to prepare for depolarization

Question 9

P wave

Answer 9

Respresents atrial depolarization

Question 10

QRS Complex

Answer 10

Respresents ventricular depolarization

Question 11

T Wave

Answer 11

Represents ventricular repolarization

Question 12

T/F A normal sinus rhythm is associated with impulses originating in the SA node

Answer 12

True

Question 13

What could cause arrhythmias and dysrhythmias?

Answer 13

Infarction
Electrolyte imbalances

Question 14

How do muscle cells signal?

Answer 14

Using Na+ K+ Ca+

Question 15

How is cardiac function controlled and where?

Answer 15

Controlled by: medulla
Through: autonomic NS, endocrine system, cardiac tissue

Question 16

Chrontropic effect:

Answer 16

affects rate of contraction

Question 17

Dromotropic effect

Answer 17

affects rate of electrical conduction

Question 18

Inotropic effect

Answer 18

Affects strength of contraction

Question 19

Which receptors maintain homeostatis?

Answer 19

• Brain
• Heart
• Blood vessels
• Kidneys

Question 20

Chemoreceptors

Answer 20

Detect chemical changes in blood (e.g. acidity)

Question 21

Baroreceptors

Answer 21

In carotid arteries
Detect heart and arterial pressure (force)

Question 22

Adrenergic receptors

Answer 22

Beta 1 and 2: heart and muscle contraction

Alpha 1 and 2: Conduction and BP

Question 23

Blood pressure

Answer 23

Force blood exerts on walls of blood vessels

How hard heart is working to pump blood
Normally 120/80

Question 24

Pulse pressure

Answer 24

Normally 40
Contractile force
Difference between systolic and diastolic

Question 25

Cardiac Output

Answer 25

Amount of blood pumped in 1 minute CO = SV x HR

Question 26

Stroke volume

Answer 26

Amount of blood ejected from the heart with each contraction/ beat in mL

Question 27

Ejection fraction

Answer 27

The volumetric fraction of blood the left ventricle pumps per contraction/ beat in percent ## Footnote Normally 50-70% Can indicate heart failure

Question 28

Afterload

Answer 28

pressure needed to eject blood out of the body

Question 28

Peripheral Vascular Resistance

Answer 28

Foce opposing the blood in peripheral circulation Increases as blood vessel diameter decreases ## Footnote Hypertension means PVR is high - Peripheral venous restriction

Question 29

Preload

Answer 29

Amount of blood returning to the heart ## Footnote Before diastole Amount in ventricle

Question 30

Antidiuretic hormone

Answer 30

Increases water reabsorption in kidneys ## Footnote Increasing blood volume and pressure

Question 31

Aldosterone

Answer 31

Increase blood volume by increasing reabsorption of Na+ in kidneys

Question 32

Renin-angiotensin-aldesterone system

Answer 32

Control/ compensatory mechanism activated when renal blood flow is decreased

Question 33

Arteries

Answer 33

Carry oxygenated blood away from the heart

Question 34

Arterioles

Answer 34

Smaller branches of arteries

Question 35

Capillaries

Answer 35

The smallest vessels with thin walls for exchange

Question 36

Veins

Answer 36

Carry deoxygenated blood back to the heart

Question 37

Venules

Answer 37

Smaller brances that return deoxygenated blood to veins

Question 38

Tunica intima

Answer 38

Inner smooth layer

Question 39

Tunica media

Answer 39

Middle muscular layer

Question 40

Tunica adventitia

Answer 40

Outer elastic layer

Question 41

Lymphatic system

Answer 41

Returns excess interstitial fluid (lymph) to circulation Immunity Lymph nodes, spleen, thymus, tonsils Fluid outflow normally exceeds fluid returned Movement of lymph resembles blood movement

Question 42

Edema

Answer 42

Tissue flooding that occurs when amount of lymph produced exceeds the capacity of the system