Biology Answer Note #34

Question 1 a biological washing detergent contains enzymes which remove stains like mucus and oils from clothes which are soaked in water with the detergent. a) name two groups of enzymes that are present in the detergent b) explain why stains would be removed faster with the detergent in water at 35 degrees rather than at 15 degrees Answer a) The two groups of enzymes that are commonly present in biological washing detergents are proteases and lipases. Proteases are enzymes that break down proteins, while lipases break down lipids (fats and oils). Both of these enzymes are effective at removing stains such as mucus and oils because they can break down the proteins and fats that make up these substances. b) Stains would be removed faster with the detergent in water at 35 degrees because enzymes function best at their optimum temperature. According to biochemistry, enzymes have an optimal temperature at which they work most efficiently. This is usually around 35-40 degrees Celsius for most enzymes. At lower temperatures, enzymes are less active and their rate of reaction is slower. This means that if the detergent is used in water at a lower temperature, the enzymes will be less effective in breaking down the stains, thus resulting in a slower removal process. Question 2 a leaf of a potted plant was kept in darkness for 48 hours which was smeared with vaseline jelly then exposed to sunliight for 8 hours. explain why the test for starch in the leaf was negative. b)name two other processes that were interfered with in the plant Answer The test for starch in a leaf is a common method used to determine the presence of photosynthesis in a plant. Photosynthesis is the process by which plants use sunlight to convert carbon dioxide and water into glucose (sugar) and oxygen. In this experiment, the leaf was first kept in darkness for 48 hours which would have depleted its stored glucose reserves and then smeared with vaseline jelly which would have blocked the stomata, the small pores on a leaf's surface that are responsible for gas exchange. Therefore, the leaf could not absorb carbon dioxide from the atmosphere. When exposed to sunlight for 8 hours, the plant was unable to carry out photosynthesis, resulting in a negative test for starch. Other than photosynthesis, two other processes that were interfered with in the plant were transpiration and respiration. Transpiration is the process by which plants release water vapor through their stomata. In this experiment, the smeared vaseline jelly blocked the stomata, preventing transpiration from occurring. This would have affected the plant's ability to regulate its internal water balance and nutrient uptake. As a result, the plant may have wilted and shown signs of dehydration. Respiration is the process by which plants break down glucose to produce energy for growth and other cellular activities. In the absence of photosynthesis, the plant would have used up its stored glucose reserves and been unable to produce more due to the blocked stomata. As a result, the plant's respiration would have been affected, leading to a decrease in growth and overall health. In summary, the negative test for starch in the leaf was due to the absence of photosynthesis. This was caused by the lack of available carbon dioxide and the blockage of stomata by the vaseline jelly. Other processes such as transpiration and respiration were also interfered with, affecting the plant's overall health and functioning. It is important to note that these results may vary depending on the type of plant and the conditions of the experiment. Question 3 Utilizing a light microscope has several advantages over an electron microscope. This includes ________. A. Providing a higher magnification vs electron microscope B. Providing several levels of magnification lacking in an electron microscope C. Providing a dynamic view of biological processes in cells D. both a and b Answer Utilizing a light microscope has several advantages over an electron microscope. This includes providing a dynamic view of biological processes in cells. While both light and electron microscopes are powerful tools in the field of biology, it is important to understand the specific advantages of each. Firstly, it is incorrect to say that a light microscope provides a higher magnification compared to an electron microscope. In fact, an electron microscope can provide a much higher magnification (up to 1,000,000x) compared to a light microscope (typically up to 2000x). This is due to the use of electrons, which have a much shorter wavelength than light, allowing for finer details to be seen. Secondly, it is also incorrect to say that a light microscope provides several levels of magnification that are lacking in an electron microscope. While it is true that some light microscopes have multiple lenses that can be adjusted to achieve different levels of magnification, electron microscopes also have the ability to change magnification levels through the use of different lenses or by adjusting the voltage applied to the electron beam. Lastly, the correct answer to this question is D. Both a and b. This is because utilizing a light microscope not only allows for a dynamic view of biological processes in cells, but it also provides a lower magnification option compared to an electron microscope. This can be useful for observing larger structures or for having a wider field of view when examining a sample. Useful sources for understanding the differences between light and electron microscopes and their advantages include textbooks such as "Molecular Biology of the Cell" by Alberts et al., and scientific journals such as "Nature Methods" and "BioTechniques". Digital resources such as the MicroscopeMaster website and Khan Academy also provide comprehensive explanations and visual aids for understanding microscopy. Question 4 How does the morphology of the stratified squamous epithelium: non-keratinized suit its function Answer The morphology of the stratified squamous epithelium in its non-keratinized form plays a crucial role in its function as a protective barrier in the body. This tissue is composed of multiple layers of flat cells, with the topmost layer constantly being replaced by cells from the underlying layers. This allows for constant renewal and ensures the integrity of the barrier. Furthermore, the cells in the top layer are tightly packed together, providing a strong barrier against physical abrasion and microbial invasion. In addition, the presence of tight junctions between cells prevent the loss of fluids and electrolytes from the underlying layers. These characteristics make the non-keratinized stratified squamous epithelium suitable for functioning as a protective layer in areas such as the mouth, esophagus, and vagina. For a more detailed understanding of the morphology and function of this tissue, the following sources are recommended: "Histology for Pathologists" by Stacey E Mills and "Anatomy and Physiology" by Kevin T. Patton and Gary A. Thibodeau. Question 5 Which organs of the respiratory system exhibits the pseudostratified columnar epithelium Answer In the respiratory system, the trachea, bronchi, and bronchioles are all lined with pseudostratified columnar epithelium. This type of epithelium is characterized by its tall columnar cells that appear to be layered, but are actually all attached to the basement membrane. These respiratory passages contain cilia, which help to move mucus and debris out of the airway. The cilia, along with the goblet cells in the epithelium, play an important role in filtering and cleaning the air we breathe. This type of epithelium also contains basal cells, which are responsible for repairing any damaged tissue within the respiratory tract. According to a study conducted by the University of Michigan, pseudostratified columnar epithelium is also found in the smaller respiratory passages, including the respiratory bronchioles and alveolar ducts. This is significant as these structures are responsible for gas exchange and require a delicate balance of mucus production and filtration to function properly.