LeighLadd

Question 1

What happens to PH as temp increases?

Answer 1

PH will decrease

Question 2

What is the standard approach to engineers regulatory algorithm and what does it stand for?

Answer 2

PID
P proportional
I integral
D differential

Question 3

Where does temperature sensing occur, and where is it integrated

Answer 3

1-rostral hypothalamic preoptic area
2-skin surface sensors
3-deep body sensors

Integrated in caudal hypothalamus

Question 4

What are the 4 methods of heat transfer?

Answer 4

Evaporation (cooling only)
Convection (works with Evap and conduction)
Conduction
Radiation

Question 5

What is the most important heat transfer mechanism

Answer 5

Evaporation

There must be some convection for evaporation to work effectively.

Question 6

Where does the shivering signal come from?

Answer 6

Dorsomedial portion of the hypothalamus, stimulated by signals from the skin and spinal cord.

Question 7

What are methods of rapid control of thermogenesis?

Answer 7

Shivering

Brown fat uncoupling-increases BMR

Question 8

What are methods of slow thermogenesis control?

Answer 8

Increased thyroxine production-increases BMR. This is caused by increased TRH—increased TSH—increased thyroxine—increased BMR.
Testosterone increases BMR
Growth hormone increases BMR

Question 9

What is special about the sheeps Rita Mirabilla?

Answer 9

It forms a complex plexus where counter current exchange occurs to keep the brain cool when the body temperature is increases (due to all their wool)

Question 10

What is the phosphagen energy system?

Answer 10

ATP and phosphocreatine . It is very rapid energy supply for a high out put. Requires nothing from outside the cell, but a short endurance.

Question 11

What are the energy systems(cellular) available in horses, how long do they last, and how long to recover?

Answer 11

ATP-lasts 2 seconds, takes several seconds to replenish
Phosphocreatine-lasts 8-10 seconds, takes minutes to replenish
Glycogen lactic acid-lasts 1-2mins, takes hours/days to replenish
Aerobic metabolism-lasts indefinitely, takes hours/days to replenish

Question 12

What respiratory changes occur in high energy output?

Answer 12

1) increased pulmonary artery blood pressure and flow.
2) bronchodilation
3) increased ventilation
4) paired ventilation and perfusion
5) increased rate and depth

Question 13

What cardiac changes occur in high energy output?

Answer 13

1) muscle metaboreflex and cerebellum premonition
2) rapid positive chronotropy
3) increased SV
4) increased ventricular relaxation
5) increased excitability

Question 14

What is chronotropy

Answer 14

Increased heart rate (increased firing of the SA node)

Question 15

What is inotropy

Answer 15

Increased contraction of the myocardium (increased contractility)

Question 16

What is lusitropy?

Answer 16

Relaxation of the myocardium

Question 17

What is dromotropy

Answer 17

Increased conduction of the AV node (conduction speed)

Question 18

What is bathmotropy

Answer 18

Change in excitability. (Heart is more excitable)

Question 19

What role does angiotensin II play in increased energy response?

Answer 19

Causes vasoconstriction

Stimulates aldosterone; these two factors cause a blood pressure increase

Question 20

What is concentric hypertrophy?

Answer 20

The heart develops a larger ventricular wall for increased pressure output with the same stroke volume. Heart is slower to refill therefore HR decreases

Question 21

Where is foramen ovale?

Answer 21

Between the atria

Question 22

Describe ductus arteriosus

Answer 22

Blood vessel connecting the pulmonary artery to the proximal descending aorta. Causes the bypass of blood from the fetal lungs. At birth it becomes ligamentum arteriosum

Question 23

Describe ductus venosus

Answer 23

Shunts left umbilical blood flow directly to the inferior vena cava, allowing oxygenated blood from the placenta to bypass the liver.

Question 24

Describe the effects of birth in the thoracic system in the neonate

Answer 24

First breath overcomes strong surface tension. The loss of placental blood flow doubles systemic vascular resistance.
The expansion of lungs massively reduces pulmonary vascular resistance.
All of these cause reversal of pressure gradients in the aorta, pulmonary artery and the atriums

Question 25

Describe the post natal respiratory system

Answer 25

Thoracic compliance is greater so tidal volume (normal inhalation) is reduced, and functional residual capacity (air in lungs at end of expiration) is reduced.
Closing volume is higher than adults.
Respiratory rate is higher than adults

Question 26

Describe the post natal cardiac system

Answer 26

Less contractile tissue per gram of ventricle
Lower ventricular compliance
Minimal cardiac reserve (how hard it can pump blood)
Cardiac output will be increased only by rate
SNS not developed

Question 27

List the local controls of the cardiorespiratory system at rest

Answer 27

Myogenic autoregularion
Arterial flow regulation
Tissue autoregularion (acid or purine sensing)

Question 28

List the systemic factors that control cardiorespiratory function at rest

Answer 28

Baroreceptor reflex
Bainbridge reflex
Acidaemia reflex pathway
Carbon dioxide reflex pathway
Reinin-angiotensin pathway
ANP/BNP reflex pathway

Question 29

What receptors are ionotropic?

Answer 29

N-Ach

When activated they become an open ion channel. They are ligand gated ion channels.

Question 30

What are some important PArasympathetic NS functions that effect cardio and respiratory systems

Answer 30

Slows heart rate at the SA node
Slows atrioventricular take over rate and bundle conduction
Causes constriction of bronchi via M3

Question 31

What is the function of nor adrenalin in relation to cardio respiratory system

Answer 31

It is a alpha 1 and beta 1 agonist.
Vascular effects are mediated by alpha 1
Cardiac effects are mediated by beta 1

It has some alpha 2 agonist effects
No beta 2 agonist effects.

Question 32

What are noradrenaline effects on the heart?

Answer 32

Faster rate (chronotropy)
Stronger contraction( ionotropy)
Faster arterial pressure propigation (dromotropy)
Faster relaxation (lusitropy)
More excitability (bathmotropy)

Question 33

What are nor adrenaline effects on the vascular system?

Answer 33

Splenic contraction (increased PCV)
Contraction of great veins and central venous space
Contraction of pulmonary venous vasculature

Question 34

Describe the bainbridge reflex

Answer 34

An increase in atrial fill (caused by increased pressure) causes stretch receptors to communicate (via fast myelinated efferent fibres in the vagus) to cause a reduction of Vagal tone, and so increase the HR.
So cardiac output is increased.

Question 35

What are the important cardio respiratory functions of the SNS to adrenalin?

Answer 35

It is principally an alpha 2 and beta 2 agonist but has strong beta 1 action also.
B1 principally on the heart (not as much as Nad.)
B2 on the smooth muscle
A2 protects organs from high blood pressure in fight or flight.

Question 36

What activates beta 2 receptors?

Answer 36

Adrenalin

It is the only beta 2 receptor in the body. The receptors can only be activated by adrenalin

Question 37

What is ANP/BNP

Answer 37

ANP- atrial natriuretic peptide. A powerful vasoconstrictor released by muscle cells of the heart, in response to high blood volume.
BNP- brain natriuretic peptide. An amino acid secreted by ventricles of the heart in response to excessive stretch. Causes a decrease in systemic vascular resistance

Question 38

What subtype receptor is on alpha 1 receptor and what is it affect on SNS

Answer 38

Gq coupled receptor, causes smooth muscle contraction

Question 39

What subtype receptors are on alpha 2 receptor, and how do they effect SNS

Answer 39

Gi coupled receptor, causes inhibition of transmitter release and smooth muscle contraction.

Question 40

What subtype receptors do beta 2 receptors have? What is there function?

Answer 40

All three beta 2 receptors have Gs proteins. Causes heart muscle contraction and smooth muscle relaxation.