IGCSE Biology The Binomial syste,

1. Unit 1.2.3
The Binomial System

2. In this video we will :
Describe the binomial system of naming
species as an internationally agreed system
in which the scientific name of an organism is
made up of two parts showing the genus and
species

3. What is the Binomial System of Nomenclature?
•Binomial nomenclature is the biological system of
naming the organisms in which the name is
composed of two terms, where:
•the first term indicates the genus
•the second term indicates the species
of the organism
These names are known as “ Scientific names”

4. •Why do we need this
naming system?
•to standardize the naming of living
organisms.
•a particular organism will be known by
the same name all over the world.
•description of an organism will enable the
people of any part of the world to arrive at
the same exact name.
Brown Bear
- Ursus
arctos

5. Who started this system of naming
organisms?
•Organisms were first classified by a
Swedish naturalist Carolus Linnaeus
• He classified them into smaller
and more specialized groups

6. •The sequence
of classification
is:
•Kingdom,
•Phylum,
•Class,
•Order,
•Family,
•Genus,
•Species

7. Rules for Writing Binomial
Nomenclature?
•Generally, Scientific names are in Latin and written in
Italics.
•The first word indicates genus whereas the second
word indicates Species name
•Write the first letter of the genus in Capital letter and
the first letter in a specific name in Small letter.
•Both the names in the Scientific name, when
handwritten must be separately underlined.
•The name of the author occurs at the end of the
scientific name and is write down in abbreviated form.

8. Let’s look at some
examples 

9. When typed
binomial names are
always
in italics (which
indicates they are
Latin)
e.g. Homo sapiens

10. Pantera leo ( Lion)
• What do you notice about the
scientific names of the lion and
the tiger?
• They both belong to the same
Genus- Pantera but different
species- leo for lion and tigris for
tiger.

11. Examples of Plants Scientific Names
• Daucas carota
(Carrot )
Coriandrum sativum
(Coriander )
Citrus aurantium
(Orange )
Lycopersican
esculentum (Tomato)

12. Bacterial Names
• Bacteria has scientific names too
and their genus name is based on
their shape
• Cocci or Coccus are spherical in
shape, Bacilli or bacillus are rod-
shaped like Saphylococcus aures.
• Other names can be based from
the disease they give like Vibrio
cholerae.

13. ENTER YOUR TEXT
Let’s Practice 
Elephas
maximus Nymphicus
hollandicu
Pantera leo
Solanum
lycopersicu
m
Streptococcus
pneumoniae

14. ENTER YOUR TEXT
The Answers 
Elephas
maximus Nymphicus
hollandicu
Pantera leo
Solanum
lycopersicu
m
Streptococcus
pneumoniae

15. See you next
lesson ☺
Unit
ENTER YOUR TEXT
TEACHER CLAIR

16. Thank You