Circulatory Pathways

Question 1

two types of circulatory pathways

Answer 1

open
closed

Question 2

open circulatory system in present in

Answer 2

arthropods and molluscs

Question 3

how does open circulatory system work

Answer 3

blood pumped by heart passes through large vessels into open spaces or body cavities called sinuses

Question 4

closed circulatory system is present in

Answer 4

annelids and chordates

Question 5

how does closed circulatory system work

Answer 5

blood pumped by heart is always circulated through a closed network of blood vessels

Question 6

how many chambers do fishes have in their heart

Answer 6

2 (one atrium, one ventricle)

Question 7

amphibians and reptiles have how many chambers in their hearts

Answer 7

3 (two atrium, one ventricle)

Question 8

which reptile does not have a 3 chambered heart

Answer 8

crocodile

Question 9

crocodiles, birds, mammals have how many chambers in their hearts

Answer 9

4 (two atria, two ventricles)

Question 10

explain single circulation in fishes

Answer 10

heart pumps out deoxygenated blood which is oxygenated by the gills and
supplied to the body parts from where deoxygenated blood is returned to
the heart

Question 11

explain incomplete double circulation in amphibians and reptiles

Answer 11

In amphibians and reptiles, the left atrium receives oxygenated blood from the gills/lungs/skin and the right atrium
gets the deoxygenated blood from other body parts. However, they get mixed up in the single ventricle which pumps out mixed blood

Question 12

human circulatory system is also called

Answer 12

blood vascular system

Question 13

origin of circulatory system

Answer 13

mesoderm

Question 14

size of heart

Answer 14

size of clenched fist

Question 15

It is protected by a double walled membranous bag, ________________, enclosing the ___________ fluid.

Answer 15

pericardium

Question 16

septum which divides the left and right atria

Answer 16

interatrial septum

Question 16

septum which divides the left and right ventricle

Answer 16

interventricular septum

Question 17

septum between atrium and ventricle

Answer 17

atrio-ventricular septum

Question 18

valve between right atrium and right ventricle

Answer 18

tricuspid valve

Question 19

valve between left atrium and left ventricle

Answer 19

bicuspid or mitral valve

Question 20

openings of the right and left ventricles into the _________ artery and ____________ are provided with ___________ valves

Answer 20

pulmonary
aorta
semilunar

Question 21

node in right upper corner of right atrium

Answer 21

sino-atrial node

Question 22

node on lower left corner of right atrium

Answer 22

atrio-ventricular node

Question 23

atrio-ventricular bundle goes from AVN and divides into left and right branch and then spreads into _______________

Answer 23

purkinje fibres

Question 24

maximum number of action potentials that SAN can generate in a minute

Answer 24

70-75 (avg 72)

Question 25

duration of a cardiac cycle

Answer 25

0.8 seconds

Question 26

volume of blood each ventricle pumps out during a cardiac cycle also what is it called

Answer 26

70 mL
stroke volume

Question 27

cardiac output (volume of blood pumped out by each ventricle per minute)

Answer 27

5 L

Question 28

explain what lub sound is

Answer 28

first heart sound
heart when tricuspid and bicuspid valves close

Question 29

explain dub sound

Answer 29

second heart sound
heard when semilunar valves close

Question 30

what is an electrocardiograph

Answer 30

machine which is used to obtain an electrocardiogram (ECG)

Question 31

what is an electrocardiogram

Answer 31

graphical representation of electrical activity of the heart during a cardiac cycle

Question 32

to obtain ECG of a patient, where are the three electrical leads connected

Answer 32

one to each wrist and one to left ankle
for detailed, multiple leads are attached in chest region

Question 33

what does a small curve in ecg mean

Answer 33

excitation (or depolarisation) of atria
which leads to contraction of both the atria

Question 34

an upside-down sharp V in ecg means

Answer 34

depolarisation of ventricles
contraction of the ventricles

Question 35

what does a curve slightly influenced to right side in ecg mean

Answer 35

repolarisation of ventricles
relaxation of ventricles

Question 36

contraction is also called

Answer 36

systole

Question 37

relaxation is also called

Answer 37

diastole