Why is the astronaut in a space suit?
I always enjoyed asking that question to biology students. Knowing the knew the answer is one thing, but the question and the crafted discussion was a setup of what was to come. After all, I wanted to expand their view of the situation and use the discussion throughout the entire unit (3 chapters).
The space suit serves as a barrier between two environments – one suitable for the human body, and the other quite harsh – therefore, the space suit is a container similar to a can of vegetables on the grocery self.
The body within the space suit is also a container with a barrier separating different environments on each side of the barrier. Within the human body are several cavities – open spaces that are sealed spaces for organs. For instance, the chest cavity is sealed with a protective barrier to play an important role in inhaling and exhaling. Yes, another container within a container that is inside the protective space suit.
Tissues and organs (composed of tissues) are not only within the cavities, but throughout the body. Tissues are composed of two or more different types of cells working together in a common function. Surprise, surprise, surprise – cells are also containers because each cell has a protective barrier (cell membrane) separating two environments. It is through these membranes that essential materials pass through to reach their site of need for processing. Through these same membranes, the waste removal process occurs.
Cells contain individual parts with specialized functions. Are you surprised to know that many of these parts are covered with protective barriers separating two distinct environments?
Substances continually pass in and out of the cell through the membrane. Some of these movements occur naturally without the cell expending energy. On the other hand, some movements require energy to occur.
Cells are the reason we take in oxygen from the atmosphere and return carbon dioxide. Cells are the reason we eat. Cells are the reason the heart pumps blood throughout the body to transport nutrients and carry away wastes. Cells are the reason we go to the bathroom. Cells are the reason all vital activities exist.
Cells have to survive in order to reproduce. Cells require food and eliminate wastes. Cells must interact with their surrounding environment. Cells require amino acids to produce proteins. Cells contain DNA to serve as the code of life not only for itself, but for the organism as a whole. As Bruce Lipton (scientist) states, “In reality, a cell is a biological mini-me compared to the human body. A cell has every biological system that you have.” …. now, that is quite the container.