8281489
Description
Question 1
Question
Which is NOT a function of membranes?
Answer
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Separation of incompatible processes
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Creation of concentration gradients
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Packaging for transport
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Digestion of debris
Question 2
Question
Which statements about the plasma membrane are CORRECT?
Answer
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It is a fluid phospholipid bilayer with proteins and other lipids incorporated into it.
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It is permeable to hydrophobic molecules like steroid hormones.
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It restricts entry of hydrophilic and ionic (charged) molecules/
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It is always saturated.
Question 3
Question
Cholesterol acts as a fluidity buffer for the plasma membrane as it makes the phospholipid layer more viscous, but also lowers its solidifying point,
Answer
- True
- False
Question 4
Question
Proteins are unspecific to cell type.
Answer
- True
- False
Question 5
Question
There are two types of transport in regards to energy transfer: passive and active. Passive is from [blank_start]high to low[blank_end] concentration, "[blank_start]down[blank_end]" a gradient. Active is from [blank_start]low to high[blank_end] concentration, "[blank_start]up[blank_end]" a gradient.
Answer
-
high to low
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down
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low to high
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up
Question 6
Question
Facilitated diffusion is a form of [blank_start]passive[blank_end] transport where molecules are too large to diffuse through a membrane on their own. Facilitated diffusion involves [blank_start]channels, or carrier proteins[blank_end].
Channels can be "leak" channels where molecules can [blank_start]freely[blank_end] move, or they can be gated. Voltage-gated channels respond to changes in [blank_start]charge[blank_end] whereas ligand-gated channels respond to [blank_start]chemical signals[blank_end].
Answer
-
passive
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channels or carrier proteins
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freely
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charge
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chemical signals
Question 7
Question
Active transport utilises [blank_start]proteins[blank_end] that act as pumps which use [blank_start]ATP[blank_end] to move molecules [blank_start]up[blank_end] a concentration gradient. This is important for maintaining [blank_start]concentration[blank_end] of ions, and can be direct or indirect. A classic example is the [blank_start]sodium-potassium[blank_end] pump.
Answer
-
ATP
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up
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concentration
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sodium-potassium
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proteins
Question 8
Question
Which of the following is not a function of proteins?
Answer
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Signal transduction
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Cell recognition
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Linking of membranes to the cytoskeleton or ECM
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Linking of cells
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Linking of organelles