Cardiovascular system

Hi, to push you off the cliff [NOT literally! ] look up ALL the following and expand on them:-

AT REST:

1. Heart rate and breathing rate controlled by parasympathetic tone and
modulating influence of cardiac centre and respiratory centre in medulla oblongata

2. Oxygen dissociation curve (sigmoid in shape) ensures base-level saturation with O2 in lungs and release of O2 in tissues.

3. Glycogenesis prevails together with fat deposition - anabolism greater

EXERCISE:

1. increased sympathetic activity -----> Release of adrenaline (alpha + beta effects) and noradrenaline (mainly alpha) ------->

+ve chronotropic effect -----> tahycardia
+ve inotropic effect -------> increased stroke volume

2. Muscle arterioles dilate by action of beta2 adrenoceptors

3. Tachypnoea + deeper ventilation ----- > greater O2 transfer

4. O2 dissociatiion curve shifts to right (Bohr shift) due to rise in CO2 levels -----> more O2 released in tissues

5. More catabolic activity - glycogenolysis prevails