lab 3: heart and electrocardiogram

Question 1

describe lup - first heart sound

Answer 1

Ventricles contract - systole
Atria-ventricular valves close when pressure in ventricle > pressure in atrium
Sound heard with stethoscope

Question 2

describe dup - second heart sound

Answer 2

Ventricular contraction continues
Pressure in ventricles rises - forces blood into arterial system
Arterial pressure becomes > ventricular pressure
Semilunar valves close

Question 3

name the parts of heart visible from outside

Answer 3

Left ventricle
Right ventricle
Left atrium
Right atrium
Interventricular groove
Coronary vessels
Superior and inferior vena cava
Pulmonary trunk
Aorta
Pulmonary veins (on plastic model)

Question 4

name the parts of heart on the inside (internal structures)

Answer 4

Atria-ventricular valves (left and right)
Aortic semilunar valves
Pulmonary semilunar valves
Chordae tendinae

Question 5

what is ecg

Answer 5

amplified recording of electrical activity of the heart - detected at the surface of body by skin electrodes

Question 6

describe what each lead (3) is taking the difference of

Answer 6

Lead I = difference between right and left arms
Lead II = difference between right arm and left leg
Lead III = difference between left arm and left leg
Lead on right leg = ground to prevent interference from 60HvAC

Question 7

name and describe the 3 segments of ecg

Answer 7

P wave = atrial depolarization - leads to atrial contraction - systole
QRS complex = ventricular depolarization - leads to ventricular contraction - systole
(Atrial repolarization is masked by QRS complex)
T wave = ventricular repolarization - recovery/diastole

Question 8

describe ecg and definition of heart block

Answer 8

wave of electrical activity is blocked from transmitting through AV bundle
Atria and ventricles contract independently of each other
P wave is out of synchrony with much slower QRS-T wave

Question 9

describe ecg and definition of ventricular hypertrophy

Answer 9

heart failure, axis of heart shifts and results in changes in ECG

Question 10

describe ecg and definition of arrhythmia

Answer 10

irregular heartbeat - due to several factors

Question 11

where do ecg patches go and what wires attach to them

Answer 11

First patch = inside right wrist
second = inside right elbow
third = inside left elbow

Connect black (reference) - right wrist
green (negative) - right elbow
red (positive) - left elbow

Question 12

describe series of vessels from heart (pathway kinda)

Answer 12

Arteries, arterioles, capillaries, venules, veins, back to heart

Question 13

describe veins

Answer 13

low/zero pressure system - flow maintained by valves and muscular action
Veins are usually collapsed

Question 14

where is all exchange between blood and tissues done

Answer 14

in capillaries
Thin walled, 1mm in length

Question 15

describe rbcs - erythrocytes

Answer 15

Contain hemoglobin to transport oxygen
Round concave shape
No nucleus - anucleated

Question 16

describe leukocytes (gen)

Answer 16

Nucleated
Roles in immune system

Question 17

name type of leukocytes (2 categories)

Answer 17

granulocytes and agranulocytes

Question 18

how many types of granulocytes and name them

Answer 18

3
neutrophils
eosinophils
basophils

Question 19

how many types of agranulocytes and name them

Answer 19

2

Lymphocytes
monocytes

Question 20

describe granulocytes

Answer 20

Visible cytoplasmic granules - including lysosomes and single multilobed nucleus

Question 21

describe agranulocytes

Answer 21

Have cytoplasmic granules - not visible in light microscope

Question 22

describe neutrophils

Answer 22

most common
highly lobulated nucleus
most active phagocytes

Question 23

describe eosinophils

Answer 23

two lobed nucleus with specific granules that are of uniform size
Role in allergy and asthma, killing parasitic worms

Question 24

describe basophils

Answer 24

least common
have large bilobed nucleus obscured by large numerous granules
Contain histamine and other mediators of inflammation

Question 25

describe lymphocytes

Answer 25

Slightly larger than red blood cell
Large or round indented stained nucleus with variable amount of cytoplasm (depends on state of activity)

Question 26

describe monocytes

Answer 26

largest white blood cells
change name once they leave blood cell to become macrophages
Very large phagocytes

Question 27

describe the different types of lymphocytes

Answer 27

Immune response - attack cells (cell mediated response)
Produce antibodies (humoral immune response)

Question 28

describe the different types of lymphocytes

Answer 28

Immune response - attack cells (cell mediated response)
Produce antibodies (humoral immune response)