Whales are mammals which means they need to have a specialised respiratory system to be able to survive underwater for long periods of time to swim, hunt and communicate. Their bodies are adapted to aquatic conditions by having wide tails, extended flippers and in some species dorsal fins, they have also adapted their respiratory systems in the following ways.
Whales’ blood also has greater amounts of myoglobin which is an iron and oxygen binding protein found in the muscle tissue of vertebrates in general and almost all mammals, having a greater amount of this means that whales can store more oxygen and they can go longer without having to take another breath, myoglobin is only present in humans after muscle injury. Whales also absorb up to 90% of the oxygen inhaled with each breath, this makes whales very efficient and allows them to go longer without breathing, this is the opposite to humans who only absorb around 15% of oxygen inhaled. The sperm whale is among the most efficient in the world, it can hold its breath for 80-90 minutes.
Whales’ blood also has greater amounts of myoglobin which is an iron and oxygen binding protein found in the muscle tissue of vertebrates in general and almost all mammals, having a greater amount of this means that whales can store more oxygen and they can go longer without having to take another breath, myoglobin is only present in humans after muscle injury. Whales also absorb up to 90% of the oxygen inhaled with each breath, this makes whales very efficient and allows them to go longer without breathing, this is the opposite to humans who only absorb around 15% of oxygen inhaled. The sperm whale is among the most efficient in the world, it can hold its breath for 80-90 minutes.
Whales respiratory system is also adapted for when they are underwater, when they dive their heartbeat slows down and their arteries are constricted, this slows the flow of blood to certain organs without decreasing blood pressure which in turn means each breath lasts longer.
Whales ‘nostrils’ are called blowholes and are located on top of its head, this makes it easier for the whale to breath and minimizes the need to expend extra energy by lifting their head above the water, some species of whale has one and some have two. Whales also had to develop conscious or voluntary breathing, since they can only breathe at the surface, the blowhole is surrounded by muscles to prevent them taking in water when they dive.
Whales ‘nostrils’ are called blowholes and are located on top of its head, this makes it easier for the whale to breath and minimizes the need to expend extra energy by lifting their head above the water, some species of whale has one and some have two. Whales also had to develop conscious or voluntary breathing, since they can only breathe at the surface, the blowhole is surrounded by muscles to prevent them taking in water when they dive.
Whales’ trachea is also not connected to the wales throat, this allows the whales to avoid choking on food and suffocating, it also means that whales are capable of swallowing their food underwater without the issue of taking water into their lungs like most mammals. Whales also have specialized livers and urinal systems to help manage their salt intake.
Whales also maintain an awareness of their surroundings when they rest to stop themselves drowning. Whales never fall completely asleep, during periods of rest half of the whales brain will shut down while the other half remains alert so it can react quickly to predators and maintain the breathing schedule.
http://www.whalefacts.org/how-do-whales-breathe/
http://scienceline.ucsb.edu/getkey.php?key=1009
Whales also maintain an awareness of their surroundings when they rest to stop themselves drowning. Whales never fall completely asleep, during periods of rest half of the whales brain will shut down while the other half remains alert so it can react quickly to predators and maintain the breathing schedule.
http://www.whalefacts.org/how-do-whales-breathe/
http://scienceline.ucsb.edu/getkey.php?key=1009