mini study guide (Law of LaPlace)

Question 1

in spheres and cylinders what law is applicable?

Answer 1

Law of LaPlace

Question 2

what three components are involved in the Law of LaPlace?

Answer 2

relationship between the wall tension, internal pressure, and radius

Question 3

pressure is a ____ force.

Answer 3

a pushing force

Question 4

tension is a ______ force.

Answer 4

pulling force

Question 5

pressure pushes the walls of the object ____.

Answer 5

apart

Question 6

Tension holds the walls of the object _____

Answer 6

together

Question 7

what is the surface tension of a sphere equation?

Answer 7

tension = pressure x radius /2

Question 8

give examples of a sphere in the human body where you would calculate surface tension?

Answer 8

alveolus, cardiac ventricle, saccular aneurysm

Question 9

what is the surface tension of a cylinder equation?

Answer 9

tension = pressure x radius

Question 10

give examples of cylinders in the human body where we could calculate surface tension?

Answer 10

blood vessels and aortic aneurysm

Question 11

type 2 pneumocytes produce what?

Answer 11

surfactant

Question 12

when do type 2 pneumocytes begin to produce surfactant?

Answer 12

22-26 weeks gestation

Question 13

when is the peak production time for type 2 pneumocytes to produce surfactant?

Answer 13

35-36 weeks

Question 14

surfactant reduces _________ and prevents _______

Answer 14

alveolar surface tension

alveolar collapse

Question 15

each alveolus contains the same amount of _______.

Answer 15

surfactant

Question 16

larger alveoli have a relatively _____ concentration of surfactant

Answer 16

lower

Question 17

smaller alveoli have a relatively _____ concentration of surfactant

Answer 17

higher

Question 18

as the _____ changes, so does the concentration of the surfactant in the alveoli. This keeps alveolar pressure ____, which prevents smaller alveoli from?

Answer 18

radius
constant
collapsing and emptying into larger alveoli

Question 19

the ventricle develops wall tension to overcome ______.

Answer 19

afterload

Question 20

what is the equation to determine the wall tension of the left ventricle?

Answer 20

LV pressure x radius/ LV wall thickness x2

Question 21

what is three components you can see that wall tension in the left ventricle is reduced by?

Answer 21

decreased intraventricular pressure
decrease radius
increase wall thickness

Question 22

the alveolus pressure is _____ proportional to the surface tension and ____ proportional to radius alveolus

Answer 22

directly

inversely