Questions + Bonus Flashcards
a)
What components must a buffer system contain?
a weak acid and its conjugate base.
b)
What is the purpose of a buffer system?
A buffer system helps keep the pH stable by releasing acids or bases to neutralize small pH changes.
c)
Give an example of a buffer system. (1.2)
The bicarbonate buffer system in the blood maintains a stable pH. It uses carbonic acid (weak acid) and bicarbonate (conjugate base) to keep blood acidity balanced.
Dehydration vs. Hydrolysis
Dehydration Reaction:
- Removes water (H and OH) to join smaller molecules into a larger one.
- Example: Two sugars join to form starch by removing water.
Hydrolysis Reaction:
- Adds water (H and OH) to break a large molecule into smaller ones.
- Example: Starch breaks down into sugars by adding water.
Simple:
- Dehydration builds molecules by removing water.
- Hydrolysis breaks molecules by adding water.
Competitive inhibition vs noncompetitive inhibition
Competitive Inhibition:
are similar in structure to the substrate
are able to bind with the active site
block the normal substrate from binding
Noncompetitive Inhibition:
do not compete with substrate for the active site
attach to a different site on the enzyme which changes its shape causing the substrate to not bind properly
how feedback inhibition works
process that regulates metabolic pathways. When a product accumulates, it binds to an earlier enzyme, changing its shape and slowing down its activity. This prevents overproduction of the product. When the product level decreases, the inhibition stops, allowing the enzyme to work again. This mechanism helps maintain balance in the cell.
Is it likely that an enzyme that would catalyze a sugar could also catalyze protein? Explain why or why not.
No, it’s unlikely. Enzymes are very specific and usually only work with one type of molecule. Since sugars and proteins have different shapes, an enzyme that works with sugar wouldn’t usually work with protein.
Explain why the plasma membrane is described as both a fluid and a mosaic.
The plasma membrane is described as fluid because its components, like lipids and proteins, can move freely within the layer, giving it flexibility. It is called a mosaic because it is made up of different parts, such as proteins, lipids, and carbohydrates, that are arranged in a pattern, like pieces in a mosaic.
Suppose that you accidentally place a freshwater fish in a saltwater tank. What would you expect to happen to the cells in the gills of the fish? Explain.
If you accidentally put a freshwater fish in a saltwater tank, the environment around the fish is hypertonic compared to its body fluids. This means that the salt concentration outside the fish is higher than inside its cells.
Through osmosis, water would move out of the cells to try to balance the concentration, leading to dehydration (shrinkage of cells).
Medical personnel use an intravenous saline solution to treat dehydration. Why do you think they use this saltwater solution instead of using pure water?
Medical personnel use a saline solution instead of pure water to treat dehydration because saline is isotonic with the body’s cells. This means it has a similar concentration of salts, which helps maintain cell balance and prevents cells from swelling or bursting. Pure water would be hypotonic, causing water to enter the cells and potentially leading to cell damage.
What is ATP?
Adenosine triphosphate
