FORM 2 CHAPTER 1 BIODIVERSITY

CHAPTER 1

Content

1.0 Biodiversity
1.1 Diversity of organisms
1.2 Classification of organisms

2

1.1 the variety of organisms

1. Living things are 3
called organisms.

There are many
kinds of organisms on
Earth.

2. The variety of
different types

organisms on Earth
is called biodiversity

What is biodiversity?

Bio – Living things Diversity – Variety
(organisms)

Biodiversity refers to wide variety of
organisms on Earth

Where can we find biodiversity?

 The place where organisms live is called the
habitat.

 Biodiversity is found in various habitats such as
forests, ponds, deserts, seas and soil.

6

The importance of biodiversity

 Maintain the balance of nature
 Sources of food
 Attract tourists and so can contributes to the economy of the

country.
 Sources of medicine
 Raw material for industries
 Education

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 Restricting Exploitation of Forest Resources
 Reducing Pollution
 Stop overharvesting
 Protect habitat
 Endangered species act – banning the killing of endemic

and endangered animals and plants.

8

An endemic species

 A species that lives in a specific location.

 Endemic species in Malaysia :

Hornbill
Rafflesia
Orang utan
Tapir
Pitcher plant

Formative Practicre 1.1 (Textbook pg 6)

1. What is biodiversity?
2. How does biodiversity contribute to the

economy?
3. What is endemic species? Give 2 ways to

preserve and conserve endemic species.
4. Give examples of endangered species in

Malaysia.

2. How does biodiversity
contribute to the economy?

 Biodiversity is the sources of food and medicine, food
production and medicine production highly depends on
biodiversity

 Biodiversity attracts tourists and so can contributes to
the economy of the country.

 Raw material for industries.

3. What is endemic species? Give 2 ways to
preserve and conserve endemic species.

 Endemic species is the species that lives in a
specific location.

1. Enforce laws
2. Reforestation
3. Breeding centre / build man-made

habitat.

4. Give examples of endangered
species is Malaysia.

 Sumatran rhinoceros
 Malayan tapir
 Borneo elephant
 Orangutan

 https://sevenpie.com/9-endangered-animals-in-malaysia-which-will-
cease-to-exist-without-your-attention-and-help

1.2 Classification of Organisms

Group organisms into smaller group based on their common and different
characteristics.

BIODIVERSITY

ANIMALS PLANTS

1. There are two main groups of animals:

Animals

Vertebrates Invertebrates

Animal with backbones Animal without backbones

A. Invertebrates

a. More than 90% of animals are invertebrates
b. Since invertebrates have no backbone, they are

usually small in size.

c. Examples:
 Inserts such as ants, butterflies, flies, and cockroaches
 Spiders
 Crabs
 Prawns
 Worms
 Mollusks such as snails

B. Vertebrates

a. Smaller group compared to invertebrates.
However, we are more familiar with this group
of animals

b. Since vertebrates have backbone to support their
weight, many vertebrates are large in size

c. Examples:

 Elephants
 Eagles
 Whales
 Snakes
 Frogs
 Clown fish

Classification of vertebrates

Vertebrates

Amphibians Birds Reptiles

Fish Mammals



1.Common characteristics of fish

Body covered with slimy scales for protection
Have fins and tail to swim
Streamlined bodies to swim well
Breathe through gills
Poikilothermic (body temperature changes with the
 surrounding temperature)
Lay eggs
Carry out external fertilization (eggs are fertilized outside
 the female body)

B: Amphibians

1. Common characteristics of amphibians

• Body covered with moist skin
• Adults can live on land and water
• Adults breathe with lung on land and through

moist skin when in water
• Poikilothermic (body temperature changes with the

surrounding temperature)
• Lay eggs covered with jelly-like substance
• Young amphibians live in water and breathe through

gills
• Carry out external fertilization (eggs are fertilized

outside the female body)

Tortoises Snake
Crocodile

1. Common characteristics of reptiles

•Body covered with hard and dry scales for protection
•Breathe with lungs
•Lay eggs with leathery shell
•Poikilotermic (body temperature changes with
surrounding temperature)

•Carry out internal fertilization (eggs are fertilized
inside the female body)

Kingfisher

Hornbill

1.Common characteristics of birds

•Body covered with feathers
•Have wings and beak
•Breathe with lungs

• Homeothermic (body temperature remains constant)

•Lay eggs with hard shells

•Carry out internal fertilization (eggs are fertilized inside
the female body)

Camel Orangutan

Tiger

Rhinoceros Elephant

1. Common characteristics of mammals

•Body covered with hair or fur
•Breathe with lungs
• Homeothermic (body temperature remains constant)
•Give birth to live young
•Carry out internal fertilization (eggs are fertilized inside
the female body)

•Young mammals feed on milk from their mother’s
mammary glands

External fertilisation (fish and amphibian)

 Fertilisation occurs outside the body of the female.
 Both sperms and eggs released into the water

simultaneously by the male and female parents

Internal fertilisation (mammal, bird and reptile)

 Fertilisation occurs inside the body of the female.
 During mating, the male deposits his sperm into

female’s body.

Plants

Flowering Plants Non-flowering Plants

Examples Examples

Non-flowering plants

•Further divided to
•1. conifers
•2. ferns
•3. mosses

1. Conifers

 Reproduce by seeds in cones
 Vascular
 Example: casuarinas, pine

2. Ferns

 Reproduced by spores on the underside of leaves
 Vascular
 Example: Bird’s nest fern, stag’s horn fern

3. Mosses

 Reproduce by spores
 Non-vascular
 No root

Flowering plants

•Produce flower for reproduction
•Flower  fruits and seeds  new plants
•Based on the seeds they produce, flowering plants can be further
divided into 2 groups

Flowering plants

Monocotyledons Dicotyledons

Have seeds with one cotyledon Have seeds with two cotyledon

Monocotyledon Dicotyledon



• Each seed has only one cotyledon
One cotyledon

A maize grain cut into half

• Their leaves have parallel veins

Parallel
veins
Maize
Fibrous roots
• They have fibrous roots

•Mostly are herbaceous plant (plants with non-woody
stems)

•Examples: Grasses, sugar cane, banana, paddy, and
orchid plants

• Each seed has two cotyledons
Two cotyledons

A green bean (split into two)

• Their leaves have network-like veins

Balsam plant Network-like
Tap root veins
• They have fibrous tap roots

•They may be trees, shrubs or herbaceous

•Examples: Rubber and durian trees, hibiscus, morning glory
and sunflower plants

DICHOTOMOUS KEY

 A dichotomous key is a tool that allows the user to
determine the identity of items in the natural
world, such as trees, wildflowers, mammals,
reptiles, rocks, and fish.

 Keys consist of a series of choices that lead the user
to the correct name of a given item.
"Dichotomous" means "divided into two part.



Construct a dichotomous key to identify the following plants:
Maize plant, Mosses, Fern, Sunflower plant, Rose plant

1. (a)
(b)

2. (a)
(b)

3. (a)
(b)

4. (a)
(b)

Construct a dichotomous key to identify the following plants:
Maize plant, Mosses, Fern, Sunflower plant, Rose plant

1. (a) Non flowering ------ (*Mosses, Fern) go to 2
(b) Flowering -------

2. (a)Vascular ----- Fern
(b) Non-vascular ----- Mosses

3. (a)
(b)

4. (a)
(b)

Construct a dichotomous key to identify the following plants:
Maize plant, Mosses, Fern, Sunflower plant, Rose plant

1. (a) Non flowering ------ (*Mosses, Fern) go to 2
(b) Flowering ------- (*Maize plant, sunflower plant, rose plant) go to 3

2. (a)Vascular ----- Fern
(b) Non-vascular ----- Mosses

3. (a)
(b)

4. (a)
(b)

Construct a dichotomous key to identify the following plants:
Maize plant, Mosses, Fern, Sunflower plant, Rose plant

1. (a) Non flowering ------ (*Mosses, Fern) go to 2
(b) Flowering ------- (*Maize plant, sunflower plant, rose plant) go to 3

2. (a)Vascular ----- Fern
(b) Non-vascular ----- Mosses

3. (a) Monocotyledon ----
(b) Dicotyledon -----

4. (a)
(b)