division of cellular type and labour in organs

Name the main factors influencing blood pressure

• cardiac output (CO)

• peripheral resistance (PR)

• blood volume

formula for blood pressure

blood pressure = CO x PR

is there a correlation between blood pressure and CO,PR, and blood volume

blood pressure varies directly with CO, PR and blood volume

what determines cardiac output

Cardiac output is determined by venous return and neural and hormonal controls

What is resting heart rate controlled by

resting heart rate is controlled by the cardioinhibitory centre via the vagus nerves

what is stroke volume controlled by

stroke volume is controlled by venous return (end diastolic volume, or EDV)

what changes are made from the cardioacceleratory centre under stress

Under stress, the cardioacceleratory cneter increases heart rate and stroke volume

• the end systolic volume (ESV) decreases and MAP increases

what is required to maintain blood pressure

• cooperation of the heart, blood vessels and kidneys

• supervision of the brain

What is regulated by neural and hormonal regulation

cardiac output, peripheral resistance, venous pressure

What follows cardiac output

cardiac output → arterial blood pressure →peripheral resistance → capillary pressure → venous pressure → venous return → cardiac output

Name the three types of blood vessels

vein, artery , capillary

role of arteries

carries blood away from heart to distribute it to organs and tissues

Name the types of artery

elastic, muscular, arteriole

Describe structure of elastic artery

• tunica intima

  • internal elastic layer

  • endothelium

• tunica medica

• tunica externa

Describe structure of muscular artery

• tunica externa

• tunica media

• endothelium

• tunica intima

Describe structure of arteriole

Small artery

• smooth muscle cells (media)

• endothelium

• basement membrane

role of veins

carry blood back to the heart

Name types of veins

• large vein

• medium-sized vein

• venule

Structure of large and medium sized veins

• tunica externa

• tunica media

• endothelium

• tunica intima

Structure of venule

smaller vein

• tunica externa

• endothelium

Name the types of capillaries

• fenestrated capillary

• continuous capillary

What differs veins from arteries

walls are much thinner, less muscular more easily stretched

Structure of fenestrated capillary

• pores

• endothelial cells

• basement membrane

structure of continuous capillary

• endothelial cells

• basement membrane

Describe the endothelium in a typical vein

often smooth

describe the internal and external elastic membrane in typical vein

absent

Describe the tunica media in a typical vein

thin, dominated by smooth muscle cells and collagen fibres

describe tunica externa in typical vein

collagen and elastic fibres and smooth muscle cells

What can be compared between the blood vessels?

the relationship between:
- vessel diameter
- total cross-section area of vessels
- average bp
- velocity of blood flow

Vessel diameter smallest to biggest?

- capillaries
- arterioles
- venules
- muscular arteries
- veins
- elastic arteries
- venae cavae

Trends with the total cross-section area of vessels? (S-L)

- elastic arteries
- muscular arteries
- venae cavae
- veins
- arterioles
- venules
- capillaries

Order of vessels average blood pressure lowest to highest?

- venae cavae
- veins
- venules
- capillaries
- arterioles
- muscular arteries
- elastic arteries

Order of the velocity blood flow of vessels in order of lowest to highest?

- capillaries
- venules
- arterioles
- veins
- venae cavae
- muscular arteries
- elastic arteries

what is the role of vascular regulation

intrinsic control

the control of blood flow

Describe the two types of control of blood flow

1. contraction

   • vascular smooth muscle intrinsic myogenic tone

   • stimulates smooth muscle tone in response to pressure

2. vasodilation

   • vascular endothelium

     • nitric oxide

     • prostacyclin

     • EDHF

   • relaxes smooth muscle

what are adventitial cells

reactive oxygen species

endothelial cells

EDRFs and EDCFs