Prokary vs Eukary
All cells have _________ and ________ . (Name two of the four)
What is plasma membrane, cytosol, chromosomes or genetic material, ribosomes.
What is the structural difference between the Rough ER and the Smooth ER? What do these sections synthesize?
Rough ER: Contains Ribosomes --> synthesizing, folding, and modifying proteins
Smooth ER: No Ribosomes --> Synthesize Lipids/Steroids & detoxifies the cell.
Cholesterol is a naturally occurring substance that helps maintain the membranes _____ and is found in the ____ region of the phospholipid bilayer.
What is 'fluidity' and ' hydrophobic' ?
What would happen to water transport across the cell membrane if aquaporins stopped functioning?
If aquaporins ceased to function, water movement across the membrane would slow down dramatically. Water could still pass directly through the phospholipid bilayer by simple osmosis, but much more slowly.
On axes provided create line graph with correct scale and units to illustrate the data in Table 1
Correct scale and units: X axis: 10mM/box ; Y axis: 10% of Max /box
Correctly plotted line graph: Lines connect each point to previous and next.
This type of cell is generally smaller in size (1–10 µm), has circular DNA, and reproduces through binary fission.
❓What is a prokaryotic cell?
A stomach cell that produces and releases digestive enzymes likely has an extensive amount of this Endomembrane organelle.
What is the 'Golgi Complex' ?
A ____ (small/large) , ______ (positive/negative, neutral) , _______ (nonpolar/polar) molecule will be able to freely move across the cell membrane?
What is small, neutral, and nonpolar?
A common laboratory investigation involves placing a solution of starch and glucose into a dialysis bag and suspending it in a beaker of water. The setup models how molecular size affects diffusion across a semi-permeable membrane.
Which statement best describes the changes inside the dialysis bag over time?
A. Starch and glucose both leave the bag; water stays the same.
B. Glucose leaves the bag, starch stays inside, and water enters the bag.
C. Both glucose and starch stay in the bag; water leaves the bag.
D. Starch leaves the bag, glucose and water stay inside.
What is 'B'.
Glucose is a small molecule, so it can diffuse through the dialysis membrane into the beaker.
Starch is a large polysaccharide, so it cannot pass through the membrane and stays inside.
Water moves into the bag by osmosis because the bag’s solute concentration is higher than that of the beaker.
Describe the relationship between surface area-to-volume ratios , size, and the efficacy of material exchange into and out of the cell.
High SA:V ratio (small cells):
More surface area relative to the internal volume.
Efficient exchange of materials (like oxygen, nutrients, and waste) across the cell membrane.
Cells can quickly take in what they need and remove waste.
Low SA:V ratio (large cells):
Less surface area relative to the volume.
Less efficient exchange of materials.
Substances take longer to diffuse in and out, which can limit cell function or lead to cell stress.
Prokaryotes lack membrane bound organelles, a primary example is their absence of this control center organelle: the __________.
What is the nucleus? Most prokaryotes lack membranous organelles including the nucleus.
If a protein is being transported to the plasma membrane and secreted into the extracellular space, it will be transported directly from the Rough ER to the _____ to be modified.
What is the 'Golgi Complex'
Integral proteins are amphipathic. What does this mean, and why is it important for their role in transport?
What is they have both hydrophobic and hydrophilic parts, allowing them to stay anchored in the membrane and help move substances in or out of the cell?
The value of Ψ (water potential) in leaf tissue was found to be -4.5 bars. If you take the leaf tissue and place it in a 0.2 M solution of sucrose at 25°C in an open beaker, calculate the Ψ of the solution, and determine the direction of net water flow (into or out of the tissue).
The water potential of the sucrose solution is -4.92 bars, so water will move out of the leaf tissue into the solution.
Determine the external concentration of substance L that will result in one-half of maximal entry.
The response indicates that the external concentration of substance L that will result in one-half of the maximal entry rate is between 31 and 34 .
Evidence of the endosymbiotic theory includes features that chloroplasts and mitochondria have in common with prokaryotes like ..... (List 3).
M: Organelles have double membranes like prokaryotes.
A: Both organelle display susceptibility to certain antibiotics
D: DNA each organelle has it own circular DNA genome.
D: These organelle multiply/divide by pinching in half the soma process used by bacteria.
R: Both have ribosomes found in prokaryotes.
Fewer lysosomes will be available to break down macromolecules to provide the necessary inputs (glucose, monosaccharides) for cellular respiration to occur (Glucose to ATP)
Describe the characteristics of the phospholipid bilayer that permit small hydrophobic lipids molecules to pass directly across the membrane.
The response indicates that the interior of a phospholipid bilayer is hydrophobic, which allows small hydrophobic molecules to diffuse across the membrane.
Identify the most likely mode of transport across the membrane for substance L. Explain how information provided helps determine the most likely mode of transport.
The response indicates that substance L most likely crosses the membrane by active transport but instead refers to some other form of transport, such as passive transport.
The response indicates that the cells maintain an intracellular concentration of 120 , which is always greater than the concentration of substance L in the culture medium.
Predict the likely effect on the ability of substance L to enter the cells if substance L is attached to large protein instead of free in culture.
The response indicates that substance L will be unable to enter the cells if it is attached to a large protein OR the response indicates that substance L will be unable to enter the cells if it is attached to a large protein unless there is a specific cell membrane receptor for the protein.
Endosymbiont theory proposes a model for the evolution of the mitochondria. Which of the following observations best support the model?
A. Prokaryotes and eukaryotes acquire nutrients from the surrounding environment
B. Organelles such as mitochondria and the endoplasmic reticulum have membranes composes of phospholipids
C. Mitochondria and some prokaryotes share similar metabolic reactions that produce ATP
D. Eukaryotes evolved after prokaryotes and have more complex structures.
What is 'C'.
B- Major distractor- Though true the evidence does not help explain the origin of the mitochondria. Cells are typically composed of phospholipids this is not unique.
Three unknown cell types were analyzed for their organelle content.
Cell X has many mitochondria and cilia.
Cell Y has large amounts of smooth and rough ER and a large Golgi apparatus.
Cell Z lacks most organelles.
Based on these descriptions, what is the likely primary function of each cell type, and how does its organelle composition support that function?
Cell X: Likely a motile cell, such as a respiratory tract cell or sperm cell — many mitochondria supply energy for movement and cilia enable motion or fluid movement.
Cell Y: Likely a secretory cell, such as a gland cell — abundant rough ER and Golgi indicate active protein synthesis and secretion, and smooth ER suggests lipid or hormone production.
Cell Z: Likely a prokaryotic cell or mature red blood cell — absence of organelles indicates simple structure or specialization for transport of gases rather than active metabolism.
The cell membrane includes all macromolecules except nucleic acids. Identify where lipids, carbohydrates, and proteins are found in the plasma membrane and describe their functions
Lipids (phospholipids, cholesterol, glycolipids):
Form the bilayer that acts as a selective barrier.
Phospholipids create the bilayer structure.
Cholesterol helps stabilize membrane fluidity.
Glycolipids (lipids with carbohydrate chains) aid in cell recognition.
Proteins (integral, peripheral, glycoproteins):
Embedded or attached to the bilayer; function in transport, signaling, and structure.
Glycoproteins (proteins with carbohydrate chains) are important for cell recognition and communication.
Carbohydrates:
Found attached to lipids or proteins on the outer surface; they help in cell recognition and communication.
A student placed peeled grape cells into several different solutions.
The grapes gained mass in pure water,
Lost mass in grape soda,
And showed no change in mass when placed in grape juice.
Identify if the solution or grape has higher water potential for each scenario.
What is grape soda has a lower water potential than the grape cells because water moved out of the grapes, grape juice has an equal water potential, and pure water has a higher water potential because water moved into the grapes?
Based on the model explain whether the molecules shown crossing the membrane require energy to do so.
The response indicates that energy is not required for the substances to cross the membrane because the substances are being passively transported from a region of higher concentration to a region of lower concentration.