Transcript single celled orgainism power point

Singled-Celled Organisms
Protists
Bacteria
Viruses
Protists
Eukaryotes – have a nucleus
Most have mitochondria for cellular
respiration
Most have chloroplasts to make their
own food
Most live in water
There are good protists and bad protists
Good
protists are able to create O2 through
photosynthesis
Bad
protists cause disease in humans
Found in fresh water and ocean
No harmful effects on humans or environment
Bacteria
Smallest and simplest forms of life on
the earth
Prokaryotes – do not have a nucleus
Do not have most of the organelles
Have only 1 DNA molecule which
controls their functions
1 spoonful of garden soil may have 1010
bacteria
There are good bacteria and bad bacteria
Good
bacteria make oxygen and nutrients
for other plants and animals
Bad
bacteria cause disease in humans
Bacterial Disease
• Bacteria and Protists that cause disease
are called Pathogens.
• Pathogens invade the body of other
organism and interfere with the normal
cell functions.
Neisseria gonorrhoeae
Salmonella enteriditis
Viruses
Lack most of the characteristics of living
cells,therefore most scientists do not call
them living cells
Do not move around by themselves
Do not use energy
Do not grow
ALL THEY DO IS REPRODUCE!
Only have 1 piece of DNA with a
protective coating of protein
How viruses reproduce
• The virus invades another cell, that cell
is called a host cell. The virus uses
that host’s DNA to reproduce.
Influenza virus
Influenza virus
Herpes Virus
Herpes Virus
Hepatitis B virus causes both acute
and chronic liver infections
Rotaviruses infect the lining of the
intestine and cause diarrhea ,
especially in children.