cell compartmentalisation Flashcards
(23 cards)
What is cell compartmentalization, and why is it important?
(2 marks)
Cells have distinct compartments enabling specific reactions to occur efficiently.
Membranes separate compartments for isolation and organization.
Example: The nucleus isolates genetic material from cytoplasmic reactions.
What are the advantages of a compartmentalized cell structure? Provide examples. (3 marks)
Advantages:
Enhanced efficiency of biochemical processes.
Prevention of cross-reactions.
Concentration gradients enable active transport.
Examples:
Mitochondria for energy production.
Lysosomes for waste degradation.
What tools are used to study cell structures, and what do they do? (3 marks)
Microscopy: Visualizes structures using light, electron, or fluorescence.
Centrifugation: Separates organelles by density.
Molecular Markers: Identifies specific proteins or DNA.
What are the roles of the nucleus and cytoplasm?
Nucleus: Stores genetic material and is the site of transcription.
Cytoplasm: Contains organelles and facilitates intracellular transport.
How does cytoplasm compartmentalization benefit the cell? (2 marks)
Organelles like the ER, Golgi apparatus, and vesicles specialize in synthesis, transport, and secretion.
Benefits:
Streamlined metabolic pathways.
Precise intracellular communication.
What are the structural adaptations of mitochondria, and why are they important? (3 marks)
Structure: Double membrane with cristae to increase surface area.
Function: Maximizes ATP production.
Adaptations:
Matrix contains enzymes for the Krebs cycle.
High density in active cells like muscles.
How are organelle structures optimized for their functions? Provide examples. (2 marks)
Organelles’ structures are designed for their specific roles.
Examples:
Ribosomes: Small, dense structures for protein synthesis.
Golgi apparatus: Flattened sacs for sorting and modifying proteins.
How are chloroplasts adapted for photosynthesis? (3 marks)
Structure: Double membrane, thylakoid stacks (grana), and stroma.
Adaptations:
Chlorophyll in thylakoid membranes captures light efficiently.
Stroma enzymes facilitate the Calvin cycle.
What is the role of the ER, Golgi apparatus, and vesicles in protein synthesis? (3 marks)
ER:
Rough ER: Synthesizes proteins for secretion.
Smooth ER: Synthesizes lipids.
Golgi Apparatus: Modifies and packages proteins.
Vesicles: Transport proteins to their destinations.
Describe the steps of vesicle formation (3 marks)
Membrane invaginates to form a bud.
Cargo is enclosed in the vesicle.
Vesicle pinches off, facilitated by proteins like clathrin.
Describe 4 types of vesicles
Peroxisomes: Break down fatty acids.
Lysosomes: Contain digestive enzymes.
Secretory vesicles: Transport molecules outside the cell.
Transport vesicles: Move materials within the cell.
How are proteins sorted and secreted? Provide an example. (3 marks
Sorting: Proteins tagged in the ER with molecular markers.
Secretion: Exocytosis releases proteins into the extracellular environment.
Example: Insulin secretion by pancreatic cells.
: What are the functions of vesicles in the cell? (2 marks)
Hydrolytic Enzymes: Break down waste (lysosomes).
Protein Storage: Secretory vesicles store and release proteins when needed.
Intracellular Transport: Ensures efficient material delivery
How do mitochondria and chloroplasts contribute to energy transformation? (3 marks)
Mitochondria: ATP synthesis via oxidative phosphorylation; cristae enhance surface area.
Chloroplasts: Grana organize photosystems for light capture; adaptations support photosynthesis.
How do organelles work together to coordinate cellular functions? (3 marks)
mention er, golgi, vesicles, mitochondria, lysosomes
Protein synthesis example:
Nucleus: Provides genetic instructions
and then
ER: Processes proteins.
Golgi: Modifies and packages proteins.
Vesicles: Transport proteins to their destinations.
Other functions include:
Mitochondria: Produce ATP for energy.
Lysosomes: Manage waste breakdown.
Plasma Membrane: Facilitates cell communication and transport
What roles do lysosomes and peroxisomes play in waste management? (2 marks
Lysosomes: Digest macromolecules using enzymes.
Peroxisomes: Break down toxic substances like hydrogen peroxide.
Summarize the steps of protein synthesis. (3 marks)
Transcription in the nucleus.
Translation by ribosomes on the rough ER.
Modification in the Golgi apparatus.
Transport via vesicles to final destinations.
What is cell specialization, and how do stem cells contribute? (3 marks)
Definition: Process where generic cells become specific cell types.
Stem Cells:
Undifferentiated cells capable of division and specialization.
Types: Totipotent, pluripotent, multipotent.
Example: Stem cells differentiate into nerve or muscle cells.
Why is SA:V important, and how do cells adapt to maintain efficiency? (2 marks)
Importance: Higher SA:V ratios enhance material exchange, while lower ratios cause diffusion inefficiencies.
Adaptations: Microvilli in intestinal cells increase surface area.
Provide examples of specialized cells and their adaptations. (3 marks)
Nerve Cells: Long axons for signal transmission.
Red Blood Cells: Biconcave shape increases oxygen-carrying capacity.
Sperm Cells: Flagella for mobility and enzymes for penetrating egg cells.
