Cell Compartmentalization (College Board AP® Biology): Flashcards
0Still learning
Know0
Define compartmentalization.
Was this flashcard helpful?
Cards in this collection (32)
Define compartmentalization.
Compartmentalization is the separation of a cell's interior into distinct regions by membranes and membrane-bound organelles, allowing different metabolic reactions to occur in different areas.
What feature of cells allows them to establish and maintain an internal environment different from their external environment?
Their membranes, which act as barriers separating the inside of the cell (or organelle) from its surroundings.
Membranes and membrane-bound organelles in eukaryotic cells intracellular metabolic processes and specific enzymatic reactions.
Membranes and membrane-bound organelles in eukaryotic cells compartmentalize intracellular metabolic processes and specific enzymatic reactions.
True or False?
Membrane-bound organelles are found in eukaryotic cells.
True.
Membrane-bound organelles occur in eukaryotic cells, where they achieve compartmentalization on a small scale.
In what two main ways do internal membranes facilitate cellular processes?
By minimizing competing interactions between reactions
By increasing the surface area where reactions can occur
Why does keeping metabolic reactions separate benefit a cell?
It minimizes the risk of conflicting side reactions and prevents enzyme reactions being accidentally inhibited by substrates and products from other pathways.
Cells can increase their internal for reactions by housing membrane proteins within the membranes surrounding organelles.
Cells can increase their internal surface area for reactions by housing membrane proteins within the membranes surrounding organelles.
Many membrane proteins act as enzymes. Where do they carry out their catalytic role?
At the membrane itself or just to one side of it, so the reaction is localized to that region of the cell.
How does compartmentalization allow glycolysis and the Krebs cycle to proceed independently?
Glycolysis occurs in the cytosol, while the Krebs cycle and oxidative phosphorylation occur inside mitochondria, keeping the two sets of reactions physically separate.
A cell with a high demand for ATP, such as a muscle cell, can produce more to increase the number of electron transport chains.
A cell with a high demand for ATP, such as a muscle cell, can produce more mitochondria to increase the number of electron transport chains.
Which organelles would a protein-secreting cell, such as an insulin-producing pancreatic cell, increase in number?
Its ribosomes, rough ER, and Golgi apparatus, to meet the demand for secreted protein.
True or False?
A cell specialized in removing waste, such as a neutrophil, would contain a large number of lysosomes.
True.
Cells with a role in waste removal, such as neutrophils and monocytes, produce more lysosomes to fulfil that role effectively.
Define compartmentalization.
Compartmentalization is the use of membranes to separate regions of a cell, keeping specific metabolic processes apart from the rest of the cell.
How do membrane-bound organelles help a eukaryotic cell function?
They minimize competing interactions by keeping reactions separate, and they increase the surface area where reactions can occur.
How is genetic material contained differently in eukaryotic and prokaryotic cells?
Eukaryotes: DNA is enclosed in a membrane-bound nucleus.
Prokaryotes: DNA is in a region called the nucleoid, with no surrounding membrane.
In prokaryotic cells the genetic material is found in a region called the , which has no membrane.
In prokaryotic cells the genetic material is found in a region called the nucleoid, which has no membrane.
Where does energy release occur in a prokaryotic cell, given it has no mitochondria?
Across the plasma membrane (or within infoldings called mesosomes), rather than in a specialized organelle.
True or False?
Both prokaryotic and eukaryotic cells have a plasma membrane that acts as a selective barrier.
True.
Both cell types use the plasma membrane to keep their internal environment distinct from the external environment.
True or False?
Prokaryotic cells contain membrane-bound organelles such as mitochondria.
False.
Prokaryotes lack membrane-bound organelles. They carry out specialized functions in internal regions instead.
How does the intermembrane system (ER, Golgi, vesicles) differ between the two cell types?
Eukaryotes: present — used for protein synthesis and transport.
Prokaryotes: absent.
How is soluble storage material such as glycogen held in prokaryotic cells?
In storage granules, rather than in vacuoles or vesicles as in eukaryotes.
Why is compartmentalization an advantage for eukaryotic cells?
It creates partitions so that specialized, and sometimes competing, reactions can occur separately and efficiently within the same cell.
Define endosymbiosis.
Endosymbiosis is a process in which one organism lives within another; if the relationship benefits both, the engulfed organism is not digested.
What does the endosymbiotic theory explain?
The origin of eukaryotic cells — specifically how membrane-bound organelles such as mitochondria and chloroplasts arose.
According to endosymbiotic theory, where did mitochondria and chloroplasts come from?
They evolved from once free-living prokaryotic cells that were engulfed by an ancestral host cell by endocytosis.
The process by which one organism was engulfed by another and taken into the cell is .
The process by which one organism was engulfed by another and taken into the cell is endocytosis.
Give three features of mitochondria and chloroplasts that support endosymbiotic theory.
Any three of:
Their own circular DNA
70S ribosomes (like prokaryotes)
Replicate by binary fission
Double membranes
A similar size to bacteria
Why does the type of DNA found in mitochondria support endosymbiotic theory?
Mitochondria contain their own circular DNA, similar to the DNA of prokaryotes, suggesting they were once free-living prokaryotic cells.
Both mitochondria and prokaryotes replicate by a process called .
Both mitochondria and prokaryotes replicate by a process called binary fission.
True or False?
The presence of 70S ribosomes in mitochondria supports the endosymbiotic theory.
True.
70S ribosomes are the type found in prokaryotes, suggesting mitochondria descended from free-living prokaryotic cells.
True or False?
Endosymbiotic theory proposes that the nucleus was the first organelle to evolve from an engulfed prokaryote.
False.
The theory explains the origin of mitochondria and chloroplasts from engulfed prokaryotes, based on their prokaryote-like features.
Why are mitochondria and chloroplasts said to have double membranes as evidence for endosymbiosis?
A double membrane is consistent with one cell being engulfed by another — the inner membrane from the original prokaryote and the outer from the host's engulfing membrane.
Sign up to unlock flashcards
or