Bio - 002 Midterm 2 Review

Which of the following organelles has two membranes? Check all that apply

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Which of the following organelles synthesizes new membrane cell membranes?

• Golgi apparatus
• Endoplasmic reticulum
• Ribosomes
• Cell membrane

What happens when you pierce the cell membrane?

• The membrane reseals
• A tear is formed
• The membrane collapses
• The membrane falls apart

True or False: Hydrophilic molecules interact favorably with water because all or almost all of their atoms are charged and polar

• True
• False

Which of the following molecules in the cell membrane allow cells to communicate with one another?

• Cholesterol in the membrane
• DNA in the nucleus
• Membrane proteins that can bind to other cells

What is the name given to proteins that are directly attached to the lipid bilayer?

How are integral membrane proteins separated from the cell membrane?

• Using tools to physically pull them out
• Using an enzyme to digest the membrane
• Using a detergent to break up the membrane

Which of the following will make the cell membrane more fluid?

• Adding cholesterol molecules
• Shortening the hydrocarbon tails of phospholipids
• Removing carbon carbon double bonds in the hydrocarbon tails
• Raising the temperature

Predict which of the following organisms will have the highest percentage of unsaturated phospholipids in its membranes. Explain your answer.

• Antarctic fish
• Desert snake
• Polar bear
• Thermophilic bacterium living in 100 C hot spring

What kind of macromolecules help nutrients cross the lipid bilayer and enter the cytoplasm?

• Transporter proteins
• Glucose molecules that provide the energy for transport
• Water molecules bound to nutrients through hydrogen bonding
• None of the above