Exam 2 Flashcards
Match the term on the left with the appropriate description on the right.
Triglyceride A. Barrier to some
solutes, not others
Unsaturated B. Has double bonds
Semipermeable C. Require energy
Facilitated diffusion D. Lack double
bonds
Active transport E. Lipid
F. Ends at
equilibrium
Triglyceride - E
Unsaturated - B
Semipermeable - A
Facilitated diffusion - F
Active transport - C
What do we call the coiled structures in this protein?
A. Alpha helices
B. Beta sheets
C. Loops
D. Secondaries
A. Alpha helices
These coils are folded all together to create the final 3-D shape of the protein.
Tertiary
What do we call the monomers that are put together to make polypeptides?
Amino Acids
What kind of chemical reaction is used to break down polypeptides and other polymers?
Hydrolysis
HOW does ATP add energy to other molecules, for example when it is used to make a sodium pump change shape?
A. ATP releases heat
B. ATP adds a phosphate group to a molecule
C. ATP breaks disulfide bridges
D. ATP Creates double bonds
B. ATP adds a phosphate group to a molecule
What single property do ALL lipids have in common?
A. They are fatty acids
B. They form hydration shells
C. They are non-polar
D. They are hydrophobic
D. They are hydrophobic
Triglycerides can be either fats or oils at room temperature. Structurally (shape) how do the fatty acids of fats and oils differ, and what causes that difference at a molecular level?
In saturated fats, there are no double carbon bonds, more viscous, straight, and packed together. While in unsaturated fats, there are double carbon bonds, more fluid, loosely packed, and more bent. In which, saturated fats are fats while unsaturated are oils.
It is a viscous membrane. What does he see in the membrane that makes him think that?
They are saturated fatty acids and densely packed together
How would adding cholesterol effect the fluidity of this membrane (viscous)?
A. It would make it more fluid
B. It would make it more viscous
C. It would not affect fluidity
A. It would make it more fluid
The letters A-D each indicate one of the membrane proteins above. What type of membrane protein would call protein “C”? (C is stuck in but not all the way in)
Integral protein
Assume the solute concentrations (Na+, circles; Cl-, triangles) are shown at equilibrium, what (specifically) would you call protein “D”?
Cl- Channel
The area above the membrane is outside the cell, and the area below the membrane is inside the cell. How would you describe the cytoplasm?
A. Isotonic
B. Hypotonic
C. Hypertonic
B. Hypotonic
If protein “A” is part of a G-protein coupled receptor and binds to ligand, what important change will happen at protein “B”? (A characteristic of G-protein coupled receptor activation)
The GDP will be converted to GTP
What molecules make up this membrane? (head and tail)
A. Cholesterol
B. Triglycerides
C. Phospholipids
D. Steroids
C. Phospholipids
What property of those molecules allows them to form a bilayer?
Amphipathic
Based on how the solutes are illustrated, draw an arrow across the membrane showing the direction of net movement of water.
Draw an arrow going inside
Which of the following would prevent osmosis across this membrane?
A. Add a Na+ pump moving ions to the outside
B. Add a Na+ channel to allow facilitated diffusion of Na+
C. Remove any water transport proteins
D. Add a lot of unsaturated fatty acids to the phospholipids
B. Add a Na+ channel to allow facilitated diffusion of Na+
Which of the following would be able to pass through this membrane without help from a transport protein?
A. Oxygen (O2)
B. Fructose (C6H12O6)
C. Magnesium ions (Mg++)
A. Oxygen (O2)
Briefly explain why you chose the molecule you did (O2).
It is a smaller nonpolar molecule without a charge making it easier to go past the membrane without assistance. Fructose is too big and needs assistance from transport proteins. However, Mg++ is too charged.
The sodium pump is an example of active transport. List two ways you can tell from looking at the figure.
1) It goes against concentration gradient (low to high concentration)
2) It uses ATP for the Na+ pump
What “kind of transport protein is the Na+-Glucose co-transporter (at the bottom of the figure - both going the same way)?
A. Antiport
B. Symport
C. Uniport
B. Symport
Is the Na+ glucose co-transporter active or passive? How do you know?
Active because glucose goes from low to high concentration
In this example, it is part of Big Idea of Energy Transformation. What are those two forms of energy being used?
1) ATP is being used to transform glucose through the pump
2. Gradient energy
In which of the following situations would you expect cells to use receptor mediated endocytosis (RME)?
A. A macrophage removing bacteria from the bloodstream
B. A lymphocyte secreting antibodies into the bloodstream
C. A liver cell selectively removing iron from the bloodstream
D. A bone cell detecting juvenile growth hormone from the bloodstream
C. A liver cell selectively removing iron from the bloodstream
Name one other form of endocytosis
pinocytosis or phagocytosis
Acinar cells in the pancreas secrete digestive enzymes that go to the intestine to aid digestion. These enzymes are produced in the rough endoplasmic reticulum and put in large amounts into vesicles which fuse to the cell membrane, dumping their contents. What process is being used for secretion by acinar cells?
Exocytosis
What solute is this system trying to transport?
A. K+
B. Na+
C. Glucose
c. Glucose
What role is sodium (Na+) playing in this system?
It provides energy to the pump
If a molecule binds to a receptor and activates it, what do we call that molecule?
A. Hydrophilic
B. A substrate
C. A solute
D. A ligand
D. A ligand
What are TWO ways signal transduction cascades influence how cells perceive and respond to signals?
1) Diversity - cells can come in different shapes and form many different cells
2) Plasticity - cells have many different functions
Circle the option that accurately shows the conditions after diffusion.
(Sugars stay on the same side while other ions must be divided evenly on both sides)
Dehydration Synthesis
breaks down to make water
Hydrolysis
water is the reactant
Increasing the speed of diffusion
increase the concentration difference in solute
Endergonic
anabolic, higher free energy products, +∆G, building, storing free energy, decreasing entropy, non-spontaneous, and A + B –> C
Exergonic
catabolic, breaking down, -∆G, spontaneous, lower free energy products, increasing entropy, and releasing free energy
