Asked by jojo
What is a cell?
All Answers 1
Answered by
GPT-5 mini
AI
A cell is the basic structural and functional unit of all living organisms. It is the smallest unit that can carry out all processes necessary for life.
Key points
- Common features: a cell is bounded by a plasma membrane, contains cytoplasm, and carries genetic material (DNA in most cells). It performs metabolism, grows, responds to its environment, and can reproduce.
- Two major types:
- Prokaryotic cells (bacteria and archaea): smaller, simpler, no membrane-bound nucleus or organelles; DNA is usually a single circular chromosome in the cytoplasm.
- Eukaryotic cells (animals, plants, fungi, protists): larger and more complex, with a nucleus that houses DNA and membrane-bound organelles (mitochondria, endoplasmic reticulum, Golgi apparatus, etc.).
- Typical organelles/functions in eukaryotes:
- Nucleus: stores and protects DNA.
- Mitochondria: produce cellular energy (ATP).
- Ribosomes: make proteins.
- Endoplasmic reticulum and Golgi: synthesize and process proteins and lipids.
- Lysosomes/peroxisomes: break down waste and toxins.
- (In plant cells) chloroplasts: carry out photosynthesis; cell wall: structural support; large central vacuole: storage and turgor.
- Sizes: bacteria ~0.2–5 µm; most eukaryotic cells ~10–100 µm.
- Cell theory (basic principles): all living things are made of cells; the cell is the basic unit of life; all cells come from preexisting cells.
Examples: single-celled organisms (e.g., Escherichia coli, amoebas) and the trillions of specialized cells in multicellular organisms (neurons, muscle cells, red blood cells, plant leaf cells).
Note: Viruses are not cells; they require host cells to replicate and lack independent metabolism.
In short: a cell is a tiny, organized compartment that performs the activities that define life.
Key points
- Common features: a cell is bounded by a plasma membrane, contains cytoplasm, and carries genetic material (DNA in most cells). It performs metabolism, grows, responds to its environment, and can reproduce.
- Two major types:
- Prokaryotic cells (bacteria and archaea): smaller, simpler, no membrane-bound nucleus or organelles; DNA is usually a single circular chromosome in the cytoplasm.
- Eukaryotic cells (animals, plants, fungi, protists): larger and more complex, with a nucleus that houses DNA and membrane-bound organelles (mitochondria, endoplasmic reticulum, Golgi apparatus, etc.).
- Typical organelles/functions in eukaryotes:
- Nucleus: stores and protects DNA.
- Mitochondria: produce cellular energy (ATP).
- Ribosomes: make proteins.
- Endoplasmic reticulum and Golgi: synthesize and process proteins and lipids.
- Lysosomes/peroxisomes: break down waste and toxins.
- (In plant cells) chloroplasts: carry out photosynthesis; cell wall: structural support; large central vacuole: storage and turgor.
- Sizes: bacteria ~0.2–5 µm; most eukaryotic cells ~10–100 µm.
- Cell theory (basic principles): all living things are made of cells; the cell is the basic unit of life; all cells come from preexisting cells.
Examples: single-celled organisms (e.g., Escherichia coli, amoebas) and the trillions of specialized cells in multicellular organisms (neurons, muscle cells, red blood cells, plant leaf cells).
Note: Viruses are not cells; they require host cells to replicate and lack independent metabolism.
In short: a cell is a tiny, organized compartment that performs the activities that define life.
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.