In N Out
These proteins facilitate diffusion of large quantities of water in and out of the cell.
What are aquaporins?
A lower surface area to volume ratio indicates this particular property about a cell compared to a higher surface area to volume ratio.
What is decreased efficiency in waste removal and nutrient intake?
The presence of ribosomes on Rough Endoplasmic Reticulum makes it an excellent location for the production of this type of organic compound.
What are proteins?
If these structures were ruptured, toxic hydrogen peroxide would spill into the cytoplasm, resulting in cell death.
What are peroxisomes?
Plant cell walls are composed of cellulose, while fungal cell walls are composed of chitin. a group of scientists hypothesize that this difference means the cell wall has largely different functions in plant cells vs fungal cells. Alternatively, another group of scientists hypothesize that the cell walls serve similar functions. What observation supports the alternative hypothesis?
Identify the key concept
ATP hydrolysis is utilized to transport molecules across a membrane from a _______ concentration to a ______ concentration.
low; high
What is the surface area to volume ratio for the following cells (which is cell is most efficient):
1 - SA: 70, V: 140
2 - SA: 40, V: 20
3 - SA: 6.7, V: 15
1 - 0.5
2 - 2 (most efficient)
3 - 0.45
This "powerhouse of the cell" produces energy in the form of ATP.
What is the mitochondria?
A protein contains portions (Region 1) embedded within the inner region of the phospholipid bilayer. The other portions (Region 2) are exposed to the aqueous environment surrounding the cell. Describe Region 1 and Region 2.
Region 1 - nonpolar, uncharged, hydrophobic
Region 2 - polar, charged, hydrophilic
A pathogenic bacterium has been engulfed by a phagocytic cell as part of the nonspecific (innate) immune response. Which of the following best illustrates the response?
Identify the key concepts.
Phagocytosis - taking up "food" to be broken down
What breaks down food? Lysosomes
These types of molecules may pass directly through the phospholipid bilayer.
What are very small molecules (like gases and water), and nonpolar molecules (like small lipids and gases)?
Compare 3 cube-shaped cells. Which will be the most efficient at removing waste from the cytoplasm?
1 - side: 7 micrometers
2 - side: 4 micrometers
3 - side: 11 micrometers
1 - SA:V = 0.86
2 - SA:V = 1.5 - most efficient
3 - SA:V = 0.55
These 5 cellular structures are found in all cells - Prokaryotes and Eukaryotes.
What are DNA, ribosomes, cell membrane, cytoskeleton, and cytoplasm?
If a cell is exposed to a drug that inhibits the modification of proteins, this organelle is most likely to be the target of that drug.
What is the golgi apparatus?
A student placed a semipermeable membrane in a U shaped container between two chambers - Chamber A and Chamber B. The membrane permits movement of water but not salt. The student wants to vary the rate of osmosis that occurs across the membrane. Which of the following experimental designs will result in the fastest net rate of water movement into Chamber A?
Identify the key concept
Osmosis - water flows from an area of lower solute concentration to an area of higher solute concentration (an area of higher water potential to an area of lower water potential). If we want more water in Chamber A, the answer will likely include increasing the salinity of Chamber A or decreasing the salinity of Chamber B
Describe the fluid mosaic model
Mosaic - Cell membrane is composed of phospholipids, proteins, carbohydrates, and other lipids.
Fluid - The components of the membrane move around within the membrane
In an open system, what is the water potential of a solution with a -0.67 solute potential?
-0.67
These proteins are synthesized in the rough ER, modified in the golgi apparatus, and packaged up into lysosomes to break down waste or nutrients.
What are hydrolytic enzymes?
The increasing in folding of this portion of the chloroplast would increase the efficiency of photosynthesis in a plant cell.
What are the thylakoid membranes?
Which of the following best supports endosymbiotic theory?
Identify the key concept
Endosymbiotic theory - mitochondria and chloroplasts descended from ancient prokaryotic organisms engulfed by ancient eukaryotic organisms. The answer will probably include similarities between mitochondria/chloroplasts and prokaryotes - circular DNA, ribosomes (genetics). The answer could also include a double membrane as evidence of engulfment.
A cell is present in an environment where there is a net movement of water out of the cell. What kind of environment is this? What does the water potential look like inside and outside the cell? What kind of transport is this?
Hypertonic
Inside - High water potential; Outside - Low water potential
Osmosis/Passive transport
What is the solute potential of a 0.8 M salt solution at 30 degrees Celsius?
-40.3 Barrs
Not found in Prokaryotic cells, this large organelle contains a double membrane, pores, and houses chromatin.
What is the nucleus?
In most good graphs, the ____________ is labelled on the x-axis, while the _______________ is labelled on the y-axis.
independent variable; dependent variable
Which of the following best explains how the extensive folding of the inner mitochondrial membrane benefits a eukaryotic cell?
Identify the key concepts
Folding - increases surface area:volume ratio = more efficient cellular processes
Inner mitochondrial membrane (cristae) - location of the electron transport chain, which produces ATP into the mitochondrial matrix
ATP - energy "currency" of the cell.
More folding -> more efficient ATP production -> more energy