WEEK 9

Question 1

regulation of blood flow and pressure, describe blood pressure arterial and cardiac output

Answer 1

blood pressure arterial= temperature, pulse and vital signs

cardiac output= stroke volume x heart rate

Question 2

describe the regulation of heart rate

Answer 2

• sinoatrial cells are regulated by autonomic nervous system
• sympathetic activity= noradrenaline acting on beta 1 adrenergic receptors= increases heart rate
• parasympathetic activity= vagus nerve via acetylcholine acting on muscarinic receptors= heart rate decreases

Question 3

what’s tachycardia vs bradycardia

Answer 3

tachycardia= abnormally fast heart rate > may lead to fibrillation

bradycardia= heart rate slower than 60bpm

Question 4

cardiovascular regulation: describe auto regulation

Answer 4

def= local control at the blood vessel site causing immediate localised homeostatic adjustments

Question 5

what are the three vasodilation effects

Answer 5

hypoxia= decreased pressure of oxygen

hypercapnia= increased carbon dioxide in the body

acidosis= increased concentration of hydrogen in the body

Question 6

cardiovascular regulation: neural mechanisms

Answer 6

def= responds quickly to changes

vaso meter centre= a cluster of the sympathetic neuron’s in the medulla that oversee changes in blood diameter

Question 7

cardiovascular regulation: endocrine mechanisms

Answer 7

def= direct long term changes

1- renin,, angiostenin:

• increases blood pressure causing vasoconstriction
• increases blood pressure, increases blood volume

2- antidiuretic hormone

• increases blood pressure and blood volume
• vasoconstriction

Question 8

describe chemoreceptors:

peripheral receptors and central chemoreceptors

Answer 8

1- peripheral chemoreceptors:

• present in carotid and aortic bodies
• highly sensitive to hypoxia
  -sensitive to hypercapnia and acidosis

2) central chemoreceptors

• located in the medulla oblongata
• highly sensitive to hypercapnia and acidosis

Question 9

what are the 4 age related changes occurring in the blood

Answer 9

1) when getting older, a decrease in the Total body water occurs in the human body

• leads to decrease in blood volume, increase blood viscosity and more work for the heart

2) cellular changes:

• red blood cells become more rigid= impaired oxygen delivery to tissues

3) anemia

• a condition in which there is a lack of healthy red blood cells to carry adequate oxygen to body cells
• decreases oxygen delivery

4) prevalence in elderly for:

• iron deficiency
• chronic kidney disease

Question 10

what are the 3 age related changes of blood vessels and flow

Answer 10

1) arteries become less elastic

2) increase of calcium deposits on vessel wall

3) decrease of venous return

Question 11

what are the 3 age related changes to the heart

Answer 11

1- changes in heart function and structure

2- coronary eatery blood flow decreases

3- heart valve changes