CE Biology-A Summary

Part 1-General Variety Of Living Organism 

©2000 - 2002 All rights reserved. Reproduction with permission of copyright owner. Further reproduction is prohibited. Authors: K.W.Cheng(Vice-Web Host)

歡迎教師及學生使用本網站資料作學術用途，共同推廣教育，但請註明出處資料來自網站「HKCEE Support Centre」http://www.oocities.org/hk/littleuniverse1/hkce.htm OR http://hkce.iscool.net），謝謝！

若是用作出版或放在網頁上，須先知會我們。

Note: This set of WebPages is meant to help you in your revision. You have to refer to your textbook (say English Usage when doing your revision.)

Diversity of organisms - There are over million types of living things. Each types has its once characteristics to adapt to its own way of living.

Classification ¡V Organism are classified into groups at different levels according to their common external and internal features. Each group has their own characteristics.

The hierarchy of classification: Kingdom, Phylum (in animals) / Division (in plants), Class, Order, Family, Genus, Species.

The basic unit of classification is species. A species is a group of similar organisms, which can interbreed to produce fertile offspring.

Plants

Do not produce seeds

Produce seeds

Without leaf and stem

With leaves and stems (chlorophyll)

Do not produce flower

Produce flowers

Without chlorophyll

With chlorophyll (have hyphae)

Without true root (rhizoid)

With true roots and vascular tissues

Fungi ¡V saprophytic or parasitic

Algae ¡V most are green but some are brown or red

Mosses

Ferns

Gymnosperms

Angiosperms

Live in damp places

Non-flowering plants

Flowering plants

Monocotyledons ¡V parallel veins

Dicotyledons ¡V network of veins

Animal

 

Without backbone

With backbone

 

Invertebrates

Vertebrates

 

With slimy scales, gills, fins, streamlined body

With moist naked skin, webbed feet, no external ear

With hard dry scales, usually 2 pairs of pentadactyl limbs for walking

With beak, feathers, wings

With hairs, mammary glands, placenta

Fertilization takes place inside the female body. Embryo develops in the female¡¦s body

Live in water

Larva ¡V live in water and breathe wit gills

Adult ¡V breathe with lung on land and with skin in water

Fertilized inside the female body

Eggs develop tough shells like leather after fertilization

 

External fertilization

Lay eggs in water

Eggs are laid on land, often in earth or sand

Eggs are laid onto a nest

Pisces (fish)

Amphibia

Reptilia

Aves (bird)

Mammalia

Poikilotherms (body temperature fluctuates with the environment temperature)

Homiotherms (body temperature remains constant)