Tonicity
Cells/ organells
Membrane transport
enzymes/misc
Metabolism
100
What happens during crenation? during lysis?
Crenation: The cell shrivels due to water loss
Lysis: The cell bursts or breaks because there is too much water
100
In which organelle is ATP made?
Mitochondria
100
What is the difference between active and passive transport?
Active transport requires ATP, passive transport moves down/with the gradient, active transport moves up/against the gradient
100
What are 3 factors that influence the rate of diffusion and molecular movement?
Temperature (heat= faster), size of molecule (smaller= faster), chemical properties, bigger difference in concentration gradient
100
Define metabolism and metabolic pathways.
Metabolism: all of an organism’s chemical processes
Metabolic pathways: A series of steps/ chemical reactions that use enzymes to convert a reactant to a product
200
If the cell has a concentration of 0.9, and the environment has a concentration of 0.2, which way will water flow?
The water will flow into the cell
200
What is the difference between rough and smooth endoplasmic reticulum?
Smooth ER is not bound by ribosomes, while rough ER is
200
The movement of sodium and potassium is an example of what type of transport?
Active transport (pump)
200
What is the difference between a competitive and a noncompetitive inhibitor?
Competitive inhibitors bind directly to the active site while noncompetitive inhibitors bind to the enzyme, but NOT at the active site. This changes the overall shape of the enzyme and prevents the substrate from binding or makes it so that it binds less effectively.
200
What is the difference between anabolism and catabolism?
Anabolism- build molecules, consume energy (uses ATP) → endergonic
Catabolism- break down molecules, release energy (makes ATP) → exergonic
300
Why is it important to give the right saline (NaCl) concentration to a patient needing IV therapy?
If the concentration is too high, the cells may shrivel/crenate. If the concentration is too low, their cells may swell/burst.
300
What is the function of ribosomes?
Make proteins (think about the translation process from chapter 7)
300
How many Na+ ions go through a Na+/K+ pump and in what direction? How many K+ ions go through a Na+/K+ pump and in what direction?
3 Na+ ions move out of the cell, 2 K+ ions move into the cell
300
What does an enzyme do?
Lower activation energy, which means it takes less energy to complete a chemical reaction
300
Explain energy coupling
ATP couples energetically favorable reactions (net energy release), with energetically unfavorable reaction (net energy investment).
We recommend that you be able to explain the parts of this image
400
Water moves from ______ (hypo/hypertonic) to ______ (hypo/hypertonic).
Hypo to hyper
400
Where is DNA stored?
Nucleus
400
List 3 molecules/substances that can diffuse through the cell membrane
Nonpolar molecules (ex: fatty acids, steroids, vitamins), oxygen and carbon dioxide (gases) small amounts of water, very small uncharged polar molecules
400
What are 2 ways that you can increase enzyme activity?
Increase substrate concentration (until saturation), optimal environmental pH, increase enzyme concentration, increase temperature (until optimal temperature, too hot= denaturation)
400
Is hydrolysis of ATP an example of catabolism or anabolism and explain why.
Hydrolysis= catabolism, because ATP is being broken down (remember root lysis) and this produces ADP, an inorganic phosphate, and energy
500
What drives diffusion and what happens when there is no NET movement of particles?
Diffusion driven by concentration gradients, no NET movement= dynamic equilibrium (keep in mind that particles are still moving, there is just the same amount of movement from one side to another)
500
Describe the fluid mosaic model.
Membrane is a mosaic of proteins in a fluid bilayer of phospholipids. Refer to image from textbook.
500
Explain why polar molecules cannot diffuse past a cell membrane
Membrane is made of phospholipids, which have hydrophobic fatty acid tails. Hydrophobic tails repel/ don’t allow hydrophilic (polar) molecules to pass through easily
500
Why do we use negative feedback/ feedback inhibition?
Stops cells from wasting energy (if we don’t need the product)
Allows for tight control of enzyme activity
Usually reversible, noncompetitive inhibition
500
How many reactions must occur to produce the final product, based on this image?
3 reactions