Exam 1 Flashcards Preview

732 > Exam 1 > Flashcards

Flashcards in Exam 1 Deck (614)
Loading flashcards...
151

there are ____ billion capillaries in the body.

40 billion

152

the functions of circulation include:

transport of:
-nutrients and O2 to tissues
- waste and CO2 away from tissues
- hormones from one area of body to another
- heat throughout the body

153

Circulation is primarily influenced by tissue needs by:

dilation or constriction

154

cardiac output is a response to:

vascular inflow

155

Arterial pressure generally controlled independently of local tissue flow or ________

cardiac output

156

circulation is influence by :

- basic physical characteristics of blood
-physical principles affecting the flow of liquids through vessels (fluid dynamics)

157

key factors of circulation include:

- blood flow
-pressure
- resistance
- control mechanisms mediating these characteristics

158

What are the 2 circulatory systems?

1. pulmonary
2. systemic

159

List 3 characteristics of arteries:

1. transport blood under high pressure
2. strong vascular walls
3. blood flow is rapid

160

list 4 characteristics of arterioles:

1. final small branches of arterial system
2. act as control conduits - blood real ease into capillaries
3. strong muscular walls that vasoconstrict/ dilate
4. innervates by SNS only

161

Name 4 characteristics of capillaries:

1. exchange site for nutrients, wastes, electro yes, fluid, etc
2. walls - VERY thing (unicellular layer of endothelial cells)
3. contain small capillary pores
4. permeable to small molecular substance, H2O

162

Name 2 characteristics of venules:

1. collects blood from capillaries
2. gradually merge into larger veins

163

List 5 characteristics of veins:

1. transport blood from tissues to heart
2. major function: serve as blood reservoir (64% of total blood volume)
3. low pressure, thin walled
4. contain muscle- can constrict/ dilate
5. act as controllable reservoir for extra blood depending on body needs

164

The distribution of blood volume within the systemic system is:
veins =
arteries =
capillaries =

veins = 64%
arteries = 15%
capillaries = 5%

165

The distribution of blood volume within in the pulmonary system is:
total pulmonary =

= 9%

166

The distribution of blood volume for the total heart =

7%

167

blow flow is defined as:

the volume of blood flowing through a vessel, an organ, or the entire circulation in a given period (ml/min)

168

blood pressure is defined as:

the force per unit area exerted on a vessel wall by the contained blood (mmHg)

169

resistance is defined as:

opposition to flow; amount of friction blood meets when passes through the vessels

170

In the interrelationship between flow, pressure, and resistance, blood flow is affected by 2 factors:

1. pressure gradient
2. vascular resistance (can be caused by PAD)

171

Ohm's Law =

calculation of low through a vessel
(more resistance -plaque- lower blood flow)

172

Ohm's law:
F = change in P/ _____

R

173

F =

blood flow

174

change in P =

change in pressure b/n 2 ends of vessel

175

R =

resistance

176

Normal adult overall blood flow =

~5,000 ml/min = cardiac output

177

What are the 2 descriptions of blood flow?

1. Laminar (smooth, layered-together)
2. Turbulent

178

Which has less resistance? (laminar or turbulent)

laminar

179

conductance (ml/sec/mmHg) =

-measure of blood flow through a vessel for a given pressure difference

180

What is the reciprocal of resistance?

conductance