Binary fission
One cell splits into two equal halves.
A single cell
Amoeba is a living thing made of just one cell.
How could Amoeba make a new individual?
What this lesson covers
The idea
In fission, a unicellular organism divides to create new individuals; in binary fission many bacteria and protozoa split into two equal halves, in any plane or, in more organised cells, in a definite orientation.
A single cell
Amoeba is a living thing made of just one cell.
How could Amoeba make a new individual?
- By splitting into two
- By growing a flower
- By laying a seed
Fission in three cells
Open each tab.
Two equal halves
In binary fission, a cell splits into two equal halves. In a simple cell like Amoeba the split can be in any plane. In a cell with more organisation, such as Leishmania with its whip-like structure, the split follows a definite orientation.
In fission, a unicellular organism divides to create new individuals. In binary fission, many bacteria and protozoa split into two equal halves, in any plane or, in more organised cells, in a definite orientation.
Notes
In binary fission many bacteria and protozoa split into two equal halves, in any plane or, in more organised cells, in a definite orientation.
Check yourself
In binary fission a cell divides into …
Which organism can split in any plane during binary fission?
Leishmania has a whip-like structure at one end. How does its binary fission occur?
- many daughter cells at once. Dividing into many daughter cells at once is multiple fission, as in Plasmodium.
- two equal halves — correct. Yes!
- a cell and a small bud. The book describes yeast putting out small buds. Binary fission gives two equal halves.
- Leishmania. In Leishmania the fission occurs in a definite orientation in relation to its whip-like structure.
- Plasmodium. Plasmodium divides into many daughter cells at once by multiple fission.
- Amoeba — correct. Yes!
- In a definite orientation in relation to that structure — correct. Yes!
- In any plane, just like Amoeba. In Leishmania the splitting follows a definite orientation relative to the whip-like structure.
- Into many daughter cells at the same time. Dividing into many daughter cells is multiple fission, not binary fission.