Organelles Flashcards
What is the function of the Nucleus
The Nucleus is the control centre of the cell. It stores genetic material and coordinates cell activities like growth, metabolism and protein synthesis
What is the structure of the Nucleus
Nuclear Envelope: A Double membrane that surrounds the nucleus.
Nuclear Pores.
Nucleoplasm.
Chromatin.
Nucleoulus.
What does the Nucleus produce
Messenger RNA (mRNA) – Carries genetic instructions for protein synthesis.
Ribosomal RNA (rRNA) – Helps form ribosomes.
Transfer RNA (tRNA) – Assists in protein translation.
Enzymes & Regulatory Molecules – Control gene expression.
What are the main organelles the nucleus works with?
Ribosomes – Produced by the nucleolus for protein synthesis.
Endoplasmic Reticulum (ER) – Receives genetic instructions (mRNA) from the nucleus for protein production.
Golgi Apparatus – Modifies and transports proteins from the ER.
Cytoplasm – The nucleus directs cellular activities in the cytoplasm.
Nuclear Pores – Control material exchange between the nucleus and cytoplasm.
What is the Function of the Mitochondria
Mitochondria are the powerhouses of the cell, producing ATP through cellular respiration to supply energy for cellular processes.
What is the structure of mitochondria?
Double membrane: Outer membrane is smooth, inner membrane has folds (cristae) to increase surface area.
Matrix: The inner fluid-filled space where metabolic reactions occur.
Own DNA & ribosomes: Mitochondria can self-replicate and produce some of their own proteins.
What is the function of lysosomes?
Lysosomes digest and break down cell waste, old organelles, and foreign invaders using hydrolytic enzymes.
What is the structure of lysosomes?
Single-membrane vesicles filled with digestive enzymes.
Acidic interior (pH ~5) to optimize enzyme activity.
How do lysosomes protect the cell?
They engulf and digest harmful bacteria, viruses, and damaged cell parts through a process called autophagy or phagocytosis.
What is the function of peroxisomes?
Peroxisomes detoxify harmful substances (e.g., alcohol) and break down fatty acids using oxidative enzymes.
How do peroxisomes break down harmful substances?
They contain catalase, which breaks down hydrogen peroxide (H₂O₂) into water and oxygen, preventing cell damage.
What is the function of ribosomes?
Ribosomes are responsible for protein synthesis, translating mRNA into polypeptide chains.
Where are ribosomes located?
Free ribosomes – Float in the cytoplasm and make proteins for the cell’s own use.
Bound ribosomes – Attached to the rough ER, making proteins for secretion or membrane use.
What are ribosomes made of?
Ribosomes are made of ribosomal RNA (rRNA) and proteins and consist of large and small subunits.
What is the function of the Golgi apparatus?
The Golgi apparatus modifies, sorts, and packages proteins and lipids for transport inside or outside the cell.
What is the structure of the Golgi apparatus?
A stack of flattened, membrane-bound sacs called cisternae that receive vesicles from the ER.
How does the Golgi apparatus transport materials?
It packages molecules into vesicles that travel to their destination (e.g., cell membrane for secretion).
What makes the rough ER “rough”?
It is covered with ribosomes, which make proteins.
What is the function of the rough ER?
The rough ER synthesizes and processes proteins for secretion or membrane integration.
How does the rough ER interact with other organelles?
It sends proteins to the Golgi apparatus for modification and transport.
What is the function of the smooth ER?
The smooth ER synthesizes lipids, detoxifies drugs/toxins, and stores calcium ions.
What makes the smooth ER different from the rough ER?
It lacks ribosomes, so it does not make proteins but focuses on lipid synthesis and detoxification.
What organelles does the mitochondria work with?
Nucleus – Provides genetic instructions for mitochondrial proteins.
Cytoplasm – Supplies glucose and oxygen for ATP production.
Ribosomes – Help synthesize some mitochondrial proteins.
Peroxisomes – Assist in breaking down fatty acids for mitochondrial energy production.
What organelles do lysosomes work with?
Golgi apparatus – Processes and packages digestive enzymes for lysosomes.
Endosomes – Deliver waste materials to lysosomes for breakdown.
Plasma membrane – Lysosomes help remove waste by exocytosis.
Mitochondria – Provide ATP for lysosomal enzyme activity.
