DIVERSITY OF ORGANISMS Q.1 Estimates of the total number of species on Earth range from as low as 3 to 5 million to around _____ million. 4 Ans. 100 This wide range of organisms is described as diversity of organisms.

Variety of Organisms Can you find and name all the organisms in the above figure?

Q.2 Try to match the following organisms with the place where they live. 1. Shrimp A. rocky store 2. MushroomB. desert 3. PenguinC. polar region 4. CamelD. woodland 5. Hermit crabE. river Ans. 1-E 2-D 3-C 4-B 5-A The place or natural environment where each type of organism lives is called its habitat.

To help identify and study organisms, biologists sort/classify them into groups Organisms are classified into two groups: animals and plants. Sorting organisms into groups is called classification. Q.3 What is the main difference between them? (Hints: consider their ways of obtaining food) Ans. Plants make their own food but animals feed on others.

Animals are further classified, according to other features, into 2 groups: Plants are also classified into 2 groups: vertebrates (animals with backbones) invertebrates (animals without backbones) flowering plants non-flowering plants

Classification of Animals

Backbone

Invertebrates Animals without backbone

Fish Body covered with scales with gills for breathing with fins for movement cold-blooded

Amphibian Have moist, scale-less skin cold-blooded

Reptiles With hard, dry, scaly skin have lungs for breathing cold-blooded

Birds With feathers covering the body forelimbs become wings have a beak for feeding warm-blooded

Mammals With hairs on skin milk-feeding from mammary glands warm-blooded

Classification of Plants

ALGAE Without roots, stems or leaves All contain chlorophyll Example Spirogyra

FUNGI No roots, stems or leaves No chlorophyll Example:Mushrooms

MOSSES With simple stems and leaves but no roots Mainly found in damp places Example: Polytrichum

FERNS With roots, stems and leaves Produce spores for reproduction Example: Wood fern

GYMNOSPERMS With roots, stems and leaves Produce naked seeds in cones Example: Pines

ANGIOSPERMS With flowers Seeds are produced inside the fruit Example: Orchids

You Should Be Able to: 6. Use an identification key. 1. Point out that there is a large variety of living things. 2. Classify animals into vertebrates and invertebrates. 3. Classify vertebrates into fishes, amphibians, reptiles, birds and mammals. 4. Classify plants into flowering and non-flowering plants using external features. 5. Classify non-flowering plants into algae, fungi, mosses, ferns and gymnosperms.

Prepared by Fok Ping Chiu Leung Kin Lap Pang Oi Yan Tong Cho Shun Wong Siu Kit Course : EDD 5161R