HUMAN NUTRITION

NUTRITION

LIPIDS

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Ducks excrete an oily substance onto their feathers, which waterproofs them and allows them to float. The waterproofing and ability to float are due to the fact that the oil is ____ and water is ____
A
Polar, nonpolar
B
Nonpolar, polar
C
Less dense, more dense
D
Sticky, slippery
Explanation: 

Detailed explanation-1: -A special gland called the uropygial gland (or the preen gland) is one key physical trait that helps to keep ducks on top of the water. This gland, located at the base of their tail, produces an oil that the ducks spread over their bodies to make their feathers water-repellent.

Detailed explanation-2: -Ducks (and many other birds) have a special skill called preening! This is something they do to clean their feathers using their beak. They activate a preen gland which releases an oily substance all over their body. This oil acts as an insulator-or something that can keep them warm and, mostly, waterproof!

Detailed explanation-3: -Ducks have what’s called a uropygial gland or preen gland located at the base of their tails. Ducks spread this oil over their feathers to help them float. Duck feathers also interlock and trap air that gives them additional buoyancy.

Detailed explanation-4: -Ducks, as well as a number of other bird species, actually coat their feathers with an oily substance that attributes to their apparent waterproof bodies. This is done through the uropygial gland, better known as the preen gland.

There is 1 question to complete.