Living organisms diversity and principles of their classification

Unit (3) lesson (1)

Living organisms

Animals

Micro-organismsplants

The study •First : diversity of living organisms •Second : classification of living organisms

First : diversity of living organisms 1)Diversity Of Animals : • According To :

1. The Size. Big animals: (The elephant - The rhinoceros )Small animals : (Rabbit - Rat – lizard)

2. The Environment Where Animal Live .Animals Live in water : (Dolphin – Corocodile)Animals Live in land : (Horse - Dog )

3. The Way Of Feeding.4. The Shape .

First : diversity of living organisms 2)Diversity of plants :According to :

1. Length Long ( palm tree)Short weeds ( clover – gargeer )

2. The size of the leavesPlants with large size leaves (banana plant )Plants with small size leaves ( molukhiyah )

First : diversity of living organisms 3)Diversity of micro organisms :

they are living organisms that can not be seen by naked eye, but they spread everywhere around us ( in air , water and soil ).

Examples :1. Amoeba2. Euglena 3. Paramecium

Micro-organisms differ from each other in shape and way of movement .

Second : Classification Of Living Organisms Taxonomy:

It is the branch of biology that searches for the similarities and the differences among living organisms and it places the similar ones in groups according to a certain system in order to ease their study.

First : classification of plants 1. According to the external shape ( appearance ):2. According to their way of reproduction :

Classification of plants According to the external shape ( appearance ):

1.Some plants can not be distinguished into roots, stems and leaves .

Examples : algae 2.Most plants can not be distinguished into roots, stems and leaves :

Examples : maize ( corn ) , wheat , palms and camphor plants .

Classification of plants According to their way of reproduction :

A.Plants reproduce by formation of spores : A.Examples : vougheir and adiantum

B.Plants reproduce by formation of seeds :A.Gymnosperms : (seeds inside cones )

( pine plant – cycas plant )B.Angiosperms : ( seeds iside pericarp ) …..

A. Monocotyledon plants ( maize – wheat ) B. Dicotyledon plants ( bean plant – pea plant )

Second : Classification Of Living Organisms

First : classification of animals : 1. Animals with soft or supported bodies.2. Animals which called arthropods. 3. Animals which called mammals.

1. Animals with soft or supported

bodies.supported

bodies

External support

mussels snails shrim

p

Internal support

fish cow bird

Soft bodiesdon’t have support

Jellyfish octopus

2. Animals which called arthropods.( number of legs)

Arachnids( four pairs of jointed

legs)

spiderscorpi

on

Insects( three pairs of jointed

legs)

ant fly bee

Myriapods(Numerous legs)

julius scolopendra

Mammals have teeth

Have Pointed canines and

molars with sharp projections

lion tiger

have Front teeth extending

outwards to capture insectsHedgehog

Have Sharp incisors

Rodents

squirrel

lagomorphs

Rabbit

Endentates(Teethless mammals)

sloth

Natural classification of living organisms

•Species :• It is a group of more similar living organisms in shape that can reproduce to give birth to new fertile individuals which are able to reproduce and keep the existence of the species.