📌 A unicellular organism consists of one cell that performs all the functions necessary for life, whereas a multicellular organism contains several specialised cells that perform different functions.
Cell → Tissue → Organ → Organism
★ Must-know
All cells of the same organism originate from one egg cell and initially possess the same genetic information, meaning the same DNA.
Different gene expression allows cells with the same DNA to become specialised and perform different functions.
Further detail
Same DNA → different gene expression → different functions
1. What distinguishes a multicellular organism from a unicellular organism?
2. Which sequence correctly represents the organisational hierarchy from simplest to most complex?
3. What genetic feature do cells of the same organism initially share?
What distinguishes unicellular from multicellular organisms?
Unicellular organisms have one cell performing all life functions, multicellular have specialized cells.
What is the order of the organisational hierarchy in biology?
Cell → Tissue → Organ → Organism.
What do all cells of the same organism originate from?
One egg cell.
What allows cells with the same DNA to perform different functions?
Different gene expression.
What is the structural form of DNA?
Two strands wound into a double helix.
Which bases pair together in DNA?
Adenine pairs with thymine and guanine pairs with cytosine.
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