Eduqo
General Science›Ch 3: Biology›The Cell
Fundamental Structural and Functional Unit of Life
Every living organism is composed of cells, which arise from pre-existing cells through cell division. The cell maintains all metabolic activities required for life.
Smart Memory Hooks
| Feature | Prokaryotic | Eukaryotic |
|---|---|---|
| Nucleus | Absent (Nucleoid) | True Nucleus present |
| Ribosomes | 70S type | 80S type |
| Cell Size | Smaller (1-10 µm) | Larger (10-100 µm) |
| Examples | Bacteria, Blue-green algae | Plants, Animals, Fungi |
Mitochondria
(Cellular Energy Hub)
Cellular Energy Hub
Produces ATP molecules during cellular respiration.
Chloroplast
(Plant Food Maker)
Plant Food Maker
Contains chlorophyll for carrying out photosynthesis.
Lysosome
(Waste Disposal Unit)
Waste Disposal Unit
Destroys worn-out cell parts and foreign invaders.
Cell Wall
(Rigid Outer Layer)
Rigid Outer Layer
Made of cellulose; present only in plant cells.
Cell wall is present in animal cellsCell wall is present only in plant cells
Animal cells have only a flexible cell membrane, never a rigid cell wall.
Mitochondria lacks its own DNAMitochondria has its own circular DNA
Mitochondria and chloroplasts are semi-autonomous organelles with their own DNA.
Prokaryotes have membrane-bound nucleusProkaryotes lack a true membrane-bound nucleus
Their genetic material floats freely in the cytoplasm as a nucleoid region.
Q1.Which cell organelle is known as the powerhouse of the cell?
Q2.Which of the following is exclusively found in plant cells?