Arteries + Veins Flashcards
1
Q
What are Arteries?
A
carry blood from heart to tissues
2
Q
3 layers of the artery walls
A
- Tunica Adventitia (outer)
- Tunica Media (middle smooth muscular)
- Tunica Intima (inner)
3
Q
3 types of arteries
A
- ELASTIC ( ex. abdominal aorta)
- largest size
- Allow for high degree of expansion
- between heart beats - MUSCULAR ( ex. femoral artery)
- distributing arteries
- regulate flow of blood to different parts of body - ARTERIOLES ( ex. tributaries)
- narrow lumina
- thick muscular walls
- blood pressure controlled by muscular tone
4
Q
Smallest to Largest Arteries
A
Capillaries
arterioles
arteries
5
Q
Smallest to Largest Veins
A
Capillaries
venules
veins
6
Q
Veins
A
returns blood to heart
NOTE: Pulmonary veins –> carry blood from lungs to heart
7
Q
Arteries VS Veins
A
ARTERIES:
- thick walls
- more elastic fibres in tunica media
- sympathetic nervous system controls smooth muscle
- smallest vessels (arterioles) surrounded by smooth muscle
- no valves
VEINS:
- thin walls
- fewer elastic fibres
- no significant sympathetic innervation
- venules; no smooth muscles
- large vessels have valves
8
Q
3 Types of Veins
A
- LARGE (ex. inferior vena cava)
- wide bundles of smooth muscle
- well developed tunica adventitia - MEDIUM (ex. great saphenous vein)
- Valves : helps with direction of flow
- muscolvenous pump - SMALL (ex. venules)
- come together to form venous plexuses
9
Q
What gets exchanged through capillaries?
A
Oxygen
Nutrients
CO2
other materials
EXCHANGED THROUGH DIFFUSION