BIT Assignment By CHAN Wai Kay 9th June, 2000

Diversity of Organisms and Classification

Classification of Organisms Kingdom Phylum / Division Class Species

The smallest group of organisms classified which can interbreed with each other to produce fertile offspring

Two Kingdom System Animals Plants

Animal Kingdom Divided into two groups according to the presence or absence of backbone: –Invertebrates : without backbone –Vertebrates : with backbone

Invertebrates

Vertebrates Divided into 5 groups: –Fish –Amphibians –Reptiles –Birds –Mammals

Fish Aquatic Cold-blooded Body covered with slimy and wet scales Streamline body for easy movement through water Fins for balance and to control movement Gills for breathing External fertilization

Amphibians Cold-blooded Scaleless, moist skin With 4 Limbs Larvae (tadpoles) use gills for breathing; adults use lungs External fertilization

Reptiles Cold-blooded Body covered with hard, dry scales Live on land Breathe with lungs Internal fertilization; lay shelled eggs

Birds Warm-blooded With feathers and wings Beak for feeding Lungs for breathing Internal fertilization; lay shelled eggs

Mammals Warm-blooded Hairs on skin Females have mammary glands for producing milk Lungs for breathing Diaphragm present Internal fertilization; embryos develop inside mothers’ bodies

Summary -- Body Covering of Vertebrate

Activities You may examine the real specimens displayed. Homework –Textbook Page 39 HKCEE (b)

Plant Kingdom Can be divided into two groups: –Non-flowering plants –Flowering plants

Non-flowering plants 5 groups: –Fungi –Algae –Mosses –Ferns –Gymnosperms

Fungus kingdom Made up of hyphae No root, stem and leaf No chlorophyll –Saprophytic or parasitic Reproduce by forming spores

Algae Mostly aquatic May be unicellular or multicellular No root, stem or leaf Contain photosynthetic pigments (e.g. chlorophyll) for photosynthesis

Mosses With simple leaves and stems No root; with rhizoids for anchorage and absorption of water Reproduce by spores No vascular tissues Found in damp area

Ferns With true roots, stems, leaves and vascular tissues Reproduce by spores Live in damp places

Gymnosperms With true roots, stems, leaves and vascular tissues Reproduction by producing seeds –Seeds develop in cones, not enclosed by fruits  naked seeds Needle-shaped leaves to reduce water loss

Angiosperms (Flowering plants) With true roots, stems, leaves and vascular tissues With flowers for reproduction Seeds are produced inside the fruit (matured ovary)

Summary

Remarks In Form 6/7, Fungi are grouped into a Kingdom by themselves. They are not considered as plants. In Form 4/5, bacteria are grouped under Fungi. In Form 6/7, bacteria are grouped into a Kingdom by themselves.

Activities You may examine the real specimens displayed. Homework –Textbook Page 37-38, HKCEE (a) and HKCEE (a)