Diffusion, Osmosis And Enzymes

The optimum temperature refers to the temperature at which the activity of an enzyme is at its highest or fastest. Enzymes are biological catalysts that speed up chemical reactions in living organisms. Each enzyme has an optimal temperature at which it functions most efficiently. At temperatures lower than the optimum, the enzyme activity is slower, while at temperatures higher than the optimum, the enzyme may become denatured and lose its activity. Therefore, the correct answer is that the optimum temperature is where the activity of the enzyme is the fastest.

During germination, the enzyme protease becomes active and catalyzes the breakdown of proteins into amino acids. This chemical change is essential for the seed to obtain the necessary nutrients for growth and development. Amino acids are the building blocks of proteins and are required for various cellular processes. Therefore, the conversion of proteins into amino acids is crucial for the seed to utilize the stored nutrients and support its growth during germination.

Sugar solution is hypertonic to the water in the Visking tube. Water diffuses out of the tubing.

The process involved in the uptake of water by plants is osmosis. Osmosis is the movement of water molecules from an area of lower solute concentration to an area of higher solute concentration through a semipermeable membrane. In plants, water is absorbed by the roots and moves through the plant's tissues via osmosis, allowing the plant to maintain its water balance and support various physiological processes. Diffusion and active transport are also involved in nutrient uptake by plants, but osmosis specifically refers to the uptake of water. Transpiration, on the other hand, is the loss of water vapor from the plant's leaves.

Pepsin is the correct answer because it is an enzyme that is specifically designed to work in the stomach. It is secreted by the gastric glands in the stomach and is responsible for breaking down proteins into smaller peptides. Pepsin works best in the acidic environment of the stomach, where it is activated from its inactive form pepsinogen. Lipase, Maltase, and Cellulase are enzymes that work in other parts of the digestive system, but not in the stomach.

Osmosis takes place. Distilled water has low water potential than potato strips.

Water diffuses into root hair cells. Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. In the given options, oxygen diffuses from alveolus into the blood stream, carbon dioxide diffuses from the blood stream into alveolus, and digested blood diffuses from villi into the blood stream. These processes all involve the movement of substances from an area of higher concentration to an area of lower concentration, which is characteristic of diffusion. However, water diffusing into root hair cells does not involve a concentration gradient, as water moves into the cells due to the process of osmosis, where it moves from an area of lower solute concentration (outside the cell) to an area of higher solute concentration (inside the cell).

The movement of molecules is due to their kinetic energy. Bromine molecules and air molecules are constantly moving and colliding with each other. When a drop of liquid bromine is placed in the gas jar, the bromine molecules evaporate and mix with the air molecules. This causes the brown fumes of bromine vapor to slowly spread throughout the entire gas jar.

During seed germination, enzymes are needed to break down the insoluble food reserves stored in the seed into soluble substances. These enzymes, known as hydrolytic enzymes, help in the digestion of complex molecules such as starch and proteins into simple sugars and amino acids, which can be easily transported and utilized by the growing embryo. This breakdown of insoluble food into soluble substances provides the necessary nutrients and energy for the seedling to grow and develop.

Enzymes are biological catalysts made up of proteins. Proteins have a specific three-dimensional structure that is essential for their function. At high temperatures, the increased kinetic energy disrupts the weak bonds that maintain the protein's structure. This causes the protein to unfold and lose its shape, a process known as denaturation. Without its proper structure, the enzyme cannot function properly and its activity is significantly reduced or completely stopped. Therefore, the enzyme stops functioning at about 60°C because it is made up of protein and is denatured at high temperatures.