Diving Mammals

Question 1

Examples of external adaptations to diving in mammals?

Answer 1

Streamlined ( low drag), very short hair to reduce friction and conserve energy. Middle ear which fills with blood during dive. Shortened hindlimbs. Modified flippers.

Question 2

How is oxygen storage adapted in diving mammals?

Answer 2

Higher o2 saturation at lower partial pressures of o2 due to higher levels of myoglobin. higher pc02 also increases 02 affinity to hemoglobin.

Question 3

How does an enlarged spleen help in diving mammals?

Answer 3

provides larger reservoir of rbc. its contraction squeezes RBC into circulation. Also sleep/hepatic sinus (venous pool) interaction regulates haematocrit according to 02 availability.

Question 4

How does diving hypoxia contrasts to adaptation to high altitude hypoxia?

Answer 4

HAH involves increased CO and ventilation rate, whereas in diving, only single breath (fixed o2). Deep diving seals rely more on FA oxidation as it releases more energy than glycolysis.

Question 5

Cardiac adaptations to diving?

Answer 5

Bradycardia. Reduced cardiac output. (HR times SV ). Peripheral vasoconstriction. HR high pre dive, decreased during dive. increased aortic elasticity.

Question 6

what is anearobic/Aerobic dive limit (ADL)?

Answer 6

Max time animal can remain submerged without utilising anearobic resp. ADL= TOTAL O2 STORE/ DIVING METABOLIC RATE.