BIOL 2070 - LECTURE 3 EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS VERIFIED
Cryo-electron tomography is used for what?
Enhance cell details
FITB: Cell membranes enclose reactions and act as a_______ barrier
selective
True or False: filaments drive chemical reactions
True
What are the 3 main functions of cell membranes?
- Increase surface area
- Increase cell size
- Prevent free mixing across sides
FITB: _______ allow communication between environment and cell and will
enable the import/export of materials
Proteins
Correct this statement: cell membranes are rigid and have little capacity for
expansion.
Cell membranes are flexible and have capacity for expansion which allows cell growth,
changes, and movement
FITB: The membrane surrounding cells is called the ______ membrane
plasma
, What do internal membranes within a cell form?
Organelles
What are the some examples of organelles?
Lysosomes, endosomes, nucleus, golgi, mitochondria
true or false: the phospholipid bilayer of a membrane is very thick for maximum
protection.
False. its very thin
What are the main components of a typical membrane phospholipid molecule?
Hydrophilic head and two hydrophobic tails
FITB: the phospholipid bilayer has _______ characteristics
amphipathic
What is the most common type of phospholipid in the cell membrane?
Phosphatidylcholine
What is the structure of phosphatidylcholine?
- a hydrophilic head with a chlorine linked to a phosphate group
- 2 hydrocarbon chains
- Glycerol molecule that links the head and tails
The hydrophobic tails of a phospholipid are known as what?
Fatty acids
Describe the basic structure of hydrophobic tails
A hydrocarbon chain with a carboxyl group at one end that attaches the glycerol
Why do phospholipid hydrophobic tails have a kink?
A double, unsaturated bond in the chain
WITH COMPLETE SOLUTIONS VERIFIED
Cryo-electron tomography is used for what?
Enhance cell details
FITB: Cell membranes enclose reactions and act as a_______ barrier
selective
True or False: filaments drive chemical reactions
True
What are the 3 main functions of cell membranes?
- Increase surface area
- Increase cell size
- Prevent free mixing across sides
FITB: _______ allow communication between environment and cell and will
enable the import/export of materials
Proteins
Correct this statement: cell membranes are rigid and have little capacity for
expansion.
Cell membranes are flexible and have capacity for expansion which allows cell growth,
changes, and movement
FITB: The membrane surrounding cells is called the ______ membrane
plasma
, What do internal membranes within a cell form?
Organelles
What are the some examples of organelles?
Lysosomes, endosomes, nucleus, golgi, mitochondria
true or false: the phospholipid bilayer of a membrane is very thick for maximum
protection.
False. its very thin
What are the main components of a typical membrane phospholipid molecule?
Hydrophilic head and two hydrophobic tails
FITB: the phospholipid bilayer has _______ characteristics
amphipathic
What is the most common type of phospholipid in the cell membrane?
Phosphatidylcholine
What is the structure of phosphatidylcholine?
- a hydrophilic head with a chlorine linked to a phosphate group
- 2 hydrocarbon chains
- Glycerol molecule that links the head and tails
The hydrophobic tails of a phospholipid are known as what?
Fatty acids
Describe the basic structure of hydrophobic tails
A hydrocarbon chain with a carboxyl group at one end that attaches the glycerol
Why do phospholipid hydrophobic tails have a kink?
A double, unsaturated bond in the chain
