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FREE AND STUDY GAMES ABOUT MASTERING BIO CH. 7
EXAM QUESTIONS
Actual Qs and Ans Expert-Verified Explanation
This Exam contains:
-Guarantee passing score -29 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation
Question 1: What is the sodium-potassium pump?
Answer:
Moves 3 Na+ out of the cell for ever 2 K+ pumped into the cell(against their concentration gradients).
Question 2: What is a Hypotonic solution?
Answer:
Solution outside cell has LESS solutes than inside the cell, causing net movement of water INTO of the cell. Causes swelling and lysis (explosion) of cell.
Question 3: What is a Peripheral Membrane Protein?
Answer:
A protein that is not attached to the membrane. Part will be exposed to an integral protein.
Question 4: What is diffusion?
Answer:
The spontaneous movement of a substance DOWN its concentration gradient.
Question 5: How does cholesterol affect phospholipid bilayer?
Answer:
Reduces membrane fluidity at moderate temps by reducing phospholipid movmeent. Also hinders solidification by disrupting the regular packing of the phospholipids.Question 6: Six functions of membrane proteins:
Answer:
1) Transport (integral) 2) Enzymatic activity 3) Signal transduction 4) cell-cell recognition 5) intracellular joining 6) attachment to the ECM (extracellular matrix)
Question 7: What is a phospholipid bilayer made of?
Answer:
Hydrophillic heads on the outside with hydrophobic tails on the inside.
Question 8: What is the electrochemical gradient?
Answer:
Ions can have both a concentration (chemical) gradient and an electrical (voltage) gradient.
Question 9: Three types of solutions (tonicity)
Answer:
Isotonic, Hypotonic, Hypertonic
Question 10: What allows phospholipid bilayer to remain fluid longer?
Answer:
If it is rich in unsaturated hydrocarbon tails. Tails are kinked which prevents packing.
Question 11: What is Osmosis?
Answer:
Movement of water to create an equal solute concentration
Question 12: What is the Fluid Mosaic Model?
Answer:
Phospholipids are not attached, they move around. Movement allows passage of water (which is polar).Proteins cannot pass due to size. Some are embedded and can move along the membrane.
Question 13: Is the inside of a cell negative or positive?
Answer:
Negative.
Question 14: What causes solidifying of phospholipid bilayer?
Answer:
Cooler temperatures reduce fluidity.
Question 15: What is exocytosis?
Answer:
An energy requiring process in which the cell secretes biological molecules by the fusion of vesicles with the plasma membrane.Question 16: Categories of membrane proteins:
Answer:
1) Integral (aka Transmembrane) 2) Peripheral
Question 17: What are Ion Channels?
Answer:
Channel proteins that transport ions through the cell membrane.
Question 18: What is cotransport?
Answer:
A single ATP-powered pump that transports a specific solute and indirectly drives the active transport of several other solutes. Occurs when a membrane protein enables "downhill" diffusion of one solute to drive the "uphill" transport of another.
Question 19: What is Diffusion?
Answer:
Movement of solutes in water.
Question 20: What is Active Transport?
Answer:
Transport across the cell membrane that requires energy (ATP)
Question 21: What is endocytosis?
Answer:
The cell takes in biological molecules and particulate by forming new vesicles from the plasma membrane.
Question 22: What is Passive Transport?
Answer:
Transport across the cell membrane that does not require energy. Diffusion, osmosis, and fascilitated diffusion.
Question 23: What is the endoplasmic reticulum?
Answer:
Synthesies membrane proteins and lipids.
Question 24: What is an Integral Membrane Protein?
Answer:
A protein that is embedded in the phospholipid bilayer. Can go all the way through, or just partway.
Question 25: How may types of proteins are on a RBC membrane?
Answer:
More than 50.
Question 26: Define "amphipathic"
Answer:
Has both a hydrophilic region and a hydrophobic region.
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