Introduction to cv and rs

Question 1

Why is there a challenge in medicine for the pulmonary artery?

Answer 1

there is a low pressure exerted compared to the aorta

Question 2

what are vessels called that carry blood away from the heart?

Answer 2

Arteries

Question 3

What are the vessels that carry blood from organs and tissues back to the heart called?

Answer 3

veins

Question 4

what is bronchial circulation?

Answer 4

complementary to pulmonary circulation, supplying lung cells with oxygen and nutrients

Question 5

what need to happen to the pressure as it enters the capillary network?

Answer 5

it needs to significantly drop

Question 6

what do valves do in veins?

Answer 6

prevent backflow of blood because the pressure is not significant enough

Question 7

what is the blood flow into and out of the heart?

Answer 7

Vena cava
Right atrium
Right AV valve (tricuspid)
Right ventricle
Pulmonary (semi-lunar) valve
Pulmonary artery
Lungs
Left atrium
Left AV valve (bicuspid)
left ventricle
aortic (semi-lunar) valve
Aorta

Question 8

what is the tunica media in the arteries?

Answer 8

thick layer of smooth muscles

Question 9

What is the function of the smooth muscles in tunica media?

Answer 9

They contract and relax to modify the vessels diameter and the flow through the vessel

Question 10

what can smooth muscle contraction determine?

Answer 10

blood pressure
(abnormalities can restrict blood flow and airways)

Question 11

what is the activity of smooth muscle in the tunica media controlled by?

Answer 11

nerve supply, endogenous substances released from endothelium

Question 12

what is the function of endothelial cells?

Answer 12

• prevent thrombus formation - release mediators that inhibit platelet activation. Clotting is an essential part of healing but clots in the heart can be fatal
• causes relaxation/contraction of underlying smooth muscle which contributes to resistance of blood flow (mostly release relaxing substances)

Question 13

does noradrenaline promote relaxation or constrictions ?

Answer 13

Constriction

Question 14

what is vascular tone?

Answer 14

the contractile activity of vascular smooth muscle cells in the walls of small arteries and arterioles (always required to pump blood round body)

Question 15

how can you measure blood pressure?

Answer 15

BP= CO x PVR

Question 16

what is cardiac output?

Answer 16

the amount of blood pumped by the heart

Question 17

what is the peripheral vascular resistance?

Answer 17

resistance of vessels to blood flow ( how opened or closed they are?

Question 18

what effect does a closed blood vessel have on PVR

Answer 18

increases it

Question 19

what is the internal homeostatic pressure receptors called and what do they do?

Answer 19

Baroreceptors
Send signals depending on changes in blood pressure
eg. if bp is too high a signal will be sent to the heart to release less blood

Question 20

what is hypertension?

Answer 20

high blood pressure

Question 21

what is cardiac hypertrophy?

Answer 21

heart muscle thickens (harder for muscle to pump blood)

Question 22

what are examples of drugs that reduce bp by targeting the receptors that modulate BP

Answer 22

ACE inhibitors eg. ramipril
beta-blockers eg. bisoprolol

Question 23

how do ace inhibitors work?

Answer 23

increased urine loss, reducing blood volume

Question 24

what are drugs that target oedema (fluid-retention)?

Answer 24

Furosemide

Question 25

what are the two zones of the lungs?

Answer 25

Conducting and respiratory zone

Question 26

what happens in the conducting zone?

Answer 26

no gas exchange

Question 27

what happens in the respiratory zone?

Answer 27

gas exchange between air and blood (respiratory bronchioles reach alveolar sacs)

Question 28

what are the four stages of respiration?

Answer 28

- Air moves into (inspiration) or out of (expiration) the lungs - exchange of O2 and Co2 between air in lung and blood in capillaries - transport of O2 and CO2 by blood through the pulmonary and systemic circulation - exchange of O2 and Co2 between blood and tissues - tissue/ cell use of O2 and production of CO2

Question 29

why is breathing so easy?

Answer 29

Properties of the lungs - compliant and elasticity Surfactant Pleural membranes

Question 30

what sensory inputs help control breathing rhythm?

Answer 30

peripheral and central chemoreceptors (higher areas of the brain)

Question 31

what does breathing depend on?

Answer 31

respiratory muscle excitation of the diaphragm and intercostal muscles by their motor neutrons

Question 32

where does the control of neuronal activity of breathing occur?

Answer 32

medulla of the brain

Question 33

what are routes of administration for the respiratory system?

Answer 33

• Oral route - cough linctus • Inhalation- quick absorption, act locally and systematically •aerosols - nebuliser, metred-dose inhalers, dry powder inhalers • Nasal route - nasal sprays

Question 34

what are some examples of respiratory disorders?

Answer 34

Asthma, bronchitis, chronic obstructive pulmonary disease

Question 35

what is an example of a drug that leads to improved airway smooth muscle relaxation ?

Answer 35

salbutamol (beta-2 agonist)