Biology Final Exam Chapter 5

The movement of smoke through the air of the restaurant is an example of diffusion. Diffusion is the process by which particles move from an area of higher concentration to an area of lower concentration. In this case, the smoke particles move from the area where the person is smoking (higher concentration) to the rest of the restaurant (lower concentration), allowing you to breathe in some of that smoke.

Active transport is the correct answer because it is the only type of cellular transport that requires an expenditure of energy. Facilitated diffusion and osmosis are passive processes that do not require energy. Active transport, on the other hand, involves the movement of molecules or ions against their concentration gradient, which requires the input of energy in the form of ATP. This energy is used to pump molecules or ions across the cell membrane, allowing the cell to maintain or establish concentration gradients that are necessary for various cellular processes.

When a red blood cell is immersed in a hypertonic sucrose solution, the concentration of solutes outside the cell is higher than inside the cell. This creates a concentration gradient, causing water to move out of the cell through osmosis. As water leaves the cell, it will shrink the most because the sucrose molecules cannot pass through the red blood cell's plasma membrane. On the other hand, a hypotonic sucrose solution would cause water to move into the cell, leading to swelling. Urea, being able to pass through the membrane, would not cause as much water movement as sucrose. Therefore, a hypertonic sucrose solution is the best choice for causing the red blood cell to shrink the most.

A signal transduction pathway is a process that connects the reception of cell signals to the corresponding responses within the cell. It involves a series of molecular events, such as the activation of receptors on the cell surface, the transmission of signals through intracellular signaling molecules, and the activation of specific cellular responses. This pathway allows cells to interpret and respond to external signals, such as hormones or growth factors, by triggering various cellular processes, including gene expression, protein synthesis, or changes in cell behavior.

Heat is the capacity to perform work, as it can be converted into other forms of energy to do mechanical work. Entropy, on the other hand, is a measure of randomness or disorder in a system. It quantifies the number of possible arrangements or microstates that a system can have. As entropy increases, the system becomes more disordered and less organized.