Winter is the season of ice. As the sun’s energy gets redirected to the opposite hemisphere, water loses energy and forms into ice. This natural part of nature drives changes and effects throughout the natural world. But how does a liquid we can swim in become a solid we can walk on? What effects does ice have on our bodies and those of other animals? How do animals and plants protect themselves from the damaging effects of ice? So what are the effects of ice? Let’s get into it!
The formation of ice is driven by the same effects that protect our planet from solar radiation, and holds your good grade up on the refrigerator. In fact, in the molecular world, magnetism is one of the main driving forces. Water is made from one oxygen atom and two hydrogen atoms. Oxygen is negatively charged and hydrogen is positively charged, but when they come together they create a polar molecule, which means that the whole molecule has positive and negative sides. This means that just like the individual atoms themselves, the molecules can bond to each other as well. This is called hydrogen bonding, which is a very weak bond, but when enough water molecules bond together to form rigid ice, it's strong enough for people to walk on, and even for vehicles to drive on if the ice is thick enough. These same hydrogen bonds drive a lot of the chemical processes in our bodies, but that's a topic for another day.
Ice is important in the animal world but it is also dangerous. Our bodies are filled with water, and when that water freezes it can be dangerous. When water freezes it expands, and if enough ice forms in our cells, it can rupture the membrane and lead to cell death. Luckily we are warm blooded animals who are able to transfer heat around our bodies with our circulatory system, but in cases like frostbite, that blood flow has been redirected away from the extremities and towards the core vital organs, reducing heat in the hands and feet, leading to the freezing of skin, and eventually muscles, tendons and ligaments if it gets bad enough. And the rupturing of the cells in these areas paired with the lack of blood flow leads to cell death.
But not all animals are warm blooded and some animals have some cool tricks to protect themselves. Wood Frogs freeze every winter, but their cells are protected from damage because they are filled with glucose, or simple sugars, to lower the freezing temperature, and most of the water is removed from the cells. Their metabolism completely slows down and they hide under the fallen leaves in the forest until it becomes warm enough for them to thaw, their blood to start pumping again, and their muscles to warm up, allowing them to hop away.
But it's not only animals who have to adapt to freezing temperatures and protect themselves from freezing. Plants have no choice but to endure the cold and the evergreen trees are the masters of this climate. Most of a tree’s water is stored in their leaves, and deciduous trees drop their leaves before the freezing temperatures arrive, but evergreen trees hold less water in their needles, which are coated in a wax that also protects the water from freezing. This allows the trees to keep their needles and not need to use as much energy in spring to grow a completely new hair doo. This is one of the reasons they are able to stay green throughout the winter.
Ice is a part of nature. Many plants and animals rely on the effects of cold and ice but it can also be damaging as well. Humans use their blood to transfer heat around their body, frogs use sugar to protect their cells, and plants use wax to insulate their leaves. As the earth warms, ice and cold is becoming less common, which will have effects on the organisms that have evolved to survive with this part of the climate. But for now, remember to stay warm out there!
Ice and Animals
Ice and Plants