CHARACTERISTICS AND CLASSIFICATION
OF LIVING ORGANISMS
Living organisms possess a set of distinct characteristics that define
their existence and differentiate them from non-living things.
Movement refers to the ability of an organism or a specific part of
the organism to change its position or location. This action requires
energy and can occur voluntarily or involuntarily.
Respiration encompasses the chemical reactions that take place
within living cells. These reactions break down nutrient molecules,
such as sugars, to release energy that allows the organism to carry
out necessary functions.
Sensitivity denotes an organism's ability to detect and respond to
stimuli in its internal or external environment. This can include
responding to changes in temperature, light, pressure, or other
relevant factors.
Growth signifies a permanent increase in size and overall mass of
an organism. This growth can occur through an increase in cell
number or an expansion in cell size, or both.
Reproduction refers to the processes through which living organisms
generate offspring or produce new individuals of the same species. This
ensures the continuity and survival of species over time.
How Organisms are Classified----
BIONOMIAL NAMING SYSTEM
 There are millions of species of organisms on Earth
 A species is defined as a group of organisms that can
reproduce to species in these groups have more and
more features in common the more subdivided they
get
 He named organisms in Latin using the binomial
system where the scientific name of an organism is
made up of two parts starting with the genus (always
given a capital letter) and followed by the species
(starting with a lower case letter)
 When typed binomial names are always in italics
(which indicates they are Latin) e.g. Homo sapiens
 The sequence of classification is: Kingdom, Phylum,
Class, Order, Family, Genus, Species produce fertile
offspring.
Dichotomous Keys
Keys are used to identify organisms based on a series of
questions about their features.
Dichotomous means ‘branching into two’ and it leads the
user through to the name of the organism by giving two
descriptions at a
Classification systems aim to reflect evolutionary relationships between
species
Traditional biological classification systems grouped organisms based on the features that
they shared
If organisms shared more similar features then they were said to be more closely related.
Using DNA to Classify Organisms: