Biology 101 Exam 2 Study Guide Questions With Complete
Solutions
How are mitochondria and chloroplasts alike?
-Both are energy-transforming organelles
-Both has multiple membranes
-Both contain their own DNA and ribosomes
How many membranes do mitochondria have?
2
How many membranes do chloroplasts have?
3
How are mitochondria and chloroplasts different?
-Chloroplasts are only found in plants and algae
-Cholorplasts make food
-Mitochondria use sugars, fats, and other fuels to make energy
What are microtubules, microfilaments, and intermediate
filaments made of?
-Microtubules: Tubulin
-Microfilaments: Actin
-Intermediate filaments: Various proteins (keratin, lamins,
neurofilaments)
From greatest to least, list the thickness of microtubules,
microfilaments, and intermediate filaments?
,-Microtubules
-Intermediate filaments
-Microfilaments
What are differences between microtubules, microfilaments, and
intermediate filaments?
-Size
-Location
-Protein composition
-Structure
How are microtubules, microfilaments, and intermediate
filaments alike?
-Made of proteins
-Maintain cell structure and aid in movement
-All are dynamic
What is the function of the endomembrane system? (6)
-Synthesis of proteins
-Transport of proteins
-Metabolism and movement of lipids
-Detoxification of poisons
-Removal of cellular waste
-Acquisition of large materials from outside the cell
What is meant by a "Fluid-Mosaic Model?" What are the three
main components?
Means the cell membrane is flexible and made up of different
components such as lipids, proteins, and carbohydrates that
move around within the layer.
,Explain the structure and organization of phospholipids within
the plasma membrane.
Phospholipids form a bilayer with hydrophilic heads facing
outward and hydrophobic tails facing inward
True or false: Phospholipids are the main component of the
plasma membrane.
True
Why is the arrangement of phospholipids crucial to movement
across the membrane?
The arrangement is crucial because it controls the movement of
many substances across the membrane.
What does amphipathic mean?
Has both a hydrophilic and hydrophobic end
What two types of proteins are interspersed throughout the
plasma membrane?
Integral and peripheral
Where are integral and peripheral proteins located/found?
-Integral: Span the entire membrane (go all the way through the
bilayer)
-Peripheral: Found of one side of the membrane (inside)
What functions do the proteins in the plasma membrane serve?
1. Transport
2. Enzymatic activity
3. Signal transduction
, 4. Cell-cell recognition
5. Intercellular joining
6. Attachment to the cytoskeleton and extracellular matrix
Mosaic refers to the various substances that are associated with
the lipid bilayer. What are the four more in depth substances?
-Phospholipids
-Proteins
-Carbohydrate chains
-Cholesterol
What are the two different types of carbohydrates within the
plasma membrane? Where are they located?
-Glycolipids: Sugar chains attached to lipids
-Glycoproteins: Sugar chains attached to a protein
-Located on the outside of the membrane (Part of the ECM)
True or false: The carbohydrates within the plasma membrane
help cells recognize each other and from part of the cell's unique
"fingerprint."
True
Explain the freeze-fracture technique.
Freezes and splits cells to reveal proteins reveal proteins
embedded throughout the membrane, providing key evidence for
the fluid mosaic mode
What is membrane fluidity, and how does cholesterol help
maintain it?
Solutions
How are mitochondria and chloroplasts alike?
-Both are energy-transforming organelles
-Both has multiple membranes
-Both contain their own DNA and ribosomes
How many membranes do mitochondria have?
2
How many membranes do chloroplasts have?
3
How are mitochondria and chloroplasts different?
-Chloroplasts are only found in plants and algae
-Cholorplasts make food
-Mitochondria use sugars, fats, and other fuels to make energy
What are microtubules, microfilaments, and intermediate
filaments made of?
-Microtubules: Tubulin
-Microfilaments: Actin
-Intermediate filaments: Various proteins (keratin, lamins,
neurofilaments)
From greatest to least, list the thickness of microtubules,
microfilaments, and intermediate filaments?
,-Microtubules
-Intermediate filaments
-Microfilaments
What are differences between microtubules, microfilaments, and
intermediate filaments?
-Size
-Location
-Protein composition
-Structure
How are microtubules, microfilaments, and intermediate
filaments alike?
-Made of proteins
-Maintain cell structure and aid in movement
-All are dynamic
What is the function of the endomembrane system? (6)
-Synthesis of proteins
-Transport of proteins
-Metabolism and movement of lipids
-Detoxification of poisons
-Removal of cellular waste
-Acquisition of large materials from outside the cell
What is meant by a "Fluid-Mosaic Model?" What are the three
main components?
Means the cell membrane is flexible and made up of different
components such as lipids, proteins, and carbohydrates that
move around within the layer.
,Explain the structure and organization of phospholipids within
the plasma membrane.
Phospholipids form a bilayer with hydrophilic heads facing
outward and hydrophobic tails facing inward
True or false: Phospholipids are the main component of the
plasma membrane.
True
Why is the arrangement of phospholipids crucial to movement
across the membrane?
The arrangement is crucial because it controls the movement of
many substances across the membrane.
What does amphipathic mean?
Has both a hydrophilic and hydrophobic end
What two types of proteins are interspersed throughout the
plasma membrane?
Integral and peripheral
Where are integral and peripheral proteins located/found?
-Integral: Span the entire membrane (go all the way through the
bilayer)
-Peripheral: Found of one side of the membrane (inside)
What functions do the proteins in the plasma membrane serve?
1. Transport
2. Enzymatic activity
3. Signal transduction
, 4. Cell-cell recognition
5. Intercellular joining
6. Attachment to the cytoskeleton and extracellular matrix
Mosaic refers to the various substances that are associated with
the lipid bilayer. What are the four more in depth substances?
-Phospholipids
-Proteins
-Carbohydrate chains
-Cholesterol
What are the two different types of carbohydrates within the
plasma membrane? Where are they located?
-Glycolipids: Sugar chains attached to lipids
-Glycoproteins: Sugar chains attached to a protein
-Located on the outside of the membrane (Part of the ECM)
True or false: The carbohydrates within the plasma membrane
help cells recognize each other and from part of the cell's unique
"fingerprint."
True
Explain the freeze-fracture technique.
Freezes and splits cells to reveal proteins reveal proteins
embedded throughout the membrane, providing key evidence for
the fluid mosaic mode
What is membrane fluidity, and how does cholesterol help
maintain it?
