Question

BIOCHEMISTRY

1. Camels in the desert and survive for long periods without water. Their hump stores material that can produce water. What would be the contents of the hump: glycogen or fat? (Think moles of water produced during a sample fatty acid vs glucose metabolism)

2. Polar bears cannot drink sea water since it is salty and salt water is destructive to living tissue. Their diet is primarily fat from seals and fatty fish. Explain how they are able to survive without drinking water, but produce water from metabolism

3.Bears are warm blooded and during hibernation in winter their body temperature continues to stay warm. Explain

Answer 1

1) Camels usually live in the desert, where food sources are hard to come by. When a camel cannot get enough food, its body metabolizes the fat in the humps for nutrition. If the camel fails to get food for a long time, the humps will fall off, but once the camel is refueled they will stand upright again. Camel horns are a prominent feature of the desert, which helps regulate body temperature, where daytime temperatures are high and can be significantly reduced at night. By concentrating fat on their back, camels reduce heat insulation in other parts of the body during the day when temperatures are high. At night, excess heat flows through the body of the camel, so when the temperatures cool down, their body temperature is not too low.

2)

You need water to digest and eliminate toxins caused by breaking down all the proteins, so if you save water, you won't want to drink too much.
Eating ice to get water in cold places is expensive - it requires a lot of energy to melt enough ice. As a result, polar bears have evolved, so they don't have to drink free water.
The way to get water for polar bears is to eat as much seal fat as possible, but leave the rest to scavengers.

The body needs water from the body to metabolize (and break down) the protein of the meat whereas the breaking down of fat actually releases water. In other words: polar bears eat more fat and they drink less water. This is true regardless of whether the bear recently consumed seal fat or burned its own fat reserves.

3) Some animals are capable of slowing down their metabolism and deliberately entering a coma-like state of hibernation. Animals use very little energy when dormant. This allows them to avoid eating or drinking for long periods of time. In this case, the animal is completely unconscious and sleeping. Animals usually go into hibernation in the winter, when they cannot get enough food or water to survive. Depending on how much energy the animal stores before hibernation, it can last for weeks or months. The animal's body works by slowing down its processes and relying on the fat stored in it.
Hbernation slows animal metabolism, heart rate, and breathing rate. The animal's body temperature can also be significantly reduced - sometimes less than freezing! - So the animal does not use energy for heating. During hibernation, the animal's body does not need energy to stay alive. The body gets all the nutrients it needs by burning fat stored in the animal. When the temperature of the animal is too low, the body burns fat to stay warm, which prevents freezing.