Biology Of Humans?
Answer these questions in 1‒2 paragraphs each. Do your own work and cite your sources.
Save your work. Then upload your file through the “Writing Assignment 1” link in the Unit I
module on Canvas. You will need to look beyond the textbook and lectures to answer
these, and they require thought, analysis, and application of what you’ve learned.
1) A popular brand of protein powder states on its label,
RAW Matters
Heat and processing can denature protein, reducing its availability to your body. Our
USDA Certified Organic plant proteins are produced at low temperatures, preserving their
complete amino acid integrity.
Although this powder is probably a good source of protein, and while it’s true that heat
and processing can denature proteins, the rest of this statement is nonsense in several
ways.
Use what you know about protein structure to explain at least one of the ways this
statement is inaccurate or misleading.
2) An ad for a new facial moisturizer claims that it, “repairs the tiny cracks in your cell
membranes”.
Given what you know about the structure of membranes, is this statement credible?
What would happen if your cell membranes had cracks in them?
Answers:
- Proteins are large biological molecules made up of long chains of amino acids. They are vital components of the human body and perform a variety of functions, including catalyzing metabolic reactions, transporting molecules, and supporting cell structure. It is true that heat and processing can denature proteins and alter their physical structure, which can reduce their biological function and availability to the body. However, the claim that preserving the “complete amino acid integrity” of plant proteins through low temperature processing will improve their nutritional value is misleading.
Amino acid integrity refers to the arrangement of the amino acids within a protein molecule, which determines its specific three-dimensional shape and function. Denaturation can alter the shape of the protein and thus, its function, but the preservation of the individual amino acids themselves does not guarantee that the protein will retain its functional shape and perform normally. Therefore, this statement is inaccurate and misleading.
- Cell membranes are thin, semi-permeable layers that surround cells and regulate the exchange of molecules between the cell and its environment. The membranes are composed of a lipid bilayer, which consists of two layers of phospholipids. The lipid bilayer forms a fluid mosaic, where proteins and other components are embedded in a fluid matrix. Cracks in cell membranes would cause them to become permeable, leading to the uncontrolled exchange of ions and molecules across the membrane. This would result in the loss of the cell’s ability to maintain its proper internal environment, leading to cell damage or death. Therefore, the claim that a facial moisturizer can “repair the tiny cracks in your cell membranes” is not credible.
