📘 Chapter 7 – Diversity in Living Organisms

🧠 Easy

Easy Notes

🔹 1. What is Biodiversity?

Variety of living organisms on Earth.
India is rich in biodiversity.

🔹 2. Need for Classification

To study organisms easily.
To understand similarities and differences.
To identify and name organisms scientifically.

🔹 3. Basis of Classification

Cell type: Prokaryotic / Eukaryotic
Body design
Presence of tissues/organs
Mode of nutrition
Reproduction method

🔹 4. Classification of Living Organisms

🔸 A. Five Kingdoms (By R.H. Whittaker)

Kingdom	Features
Monera	Unicellular, prokaryotic (e.g., Bacteria)
Protista	Unicellular, eukaryotic (e.g., Amoeba)
Fungi	Multicellular, heterotrophic, decomposers (e.g., yeast, mushrooms)
Plantae	Multicellular, autotrophic (photosynthesis)
Animalia	Multicellular, heterotrophic, no cell wall

🔸 B. Plantae Classification

Division	Feature	Example
Thallophyta	No roots, stems, leaves	Algae
Bryophyta	Have simple stems/leaves, no vascular tissue	Moss
Pteridophyta	Have vascular tissue, no seeds	Fern
Gymnosperms	Naked seeds	Pine
Angiosperms	Seeds inside fruits	Mango, Rose

🔸 C. Animalia Classification

Based on Body Features

Porifera: Pores on body (e.g., Sponges)
Coelenterata: Body cavity, jellyfish (e.g., Hydra)
Platyhelminthes: Flatworms (e.g., Tapeworm)
Nematoda: Roundworms (e.g., Ascaris)
Annelida: Segmented body (e.g., Earthworm)
Arthropoda: Jointed legs, exoskeleton (e.g., Insects)
Mollusca: Soft body, shell (e.g., Snail)
Echinodermata: Spiny skin, marine (e.g., Starfish)
Chordata: Have backbone (e.g., Fish, Birds, Mammals)

✅ MCQs

Who gave the five kingdom classification?
a) Aristotle
b) R.H. Whittaker
c) Linnaeus
d) Darwin
Which kingdom includes bacteria?
a) Protista
b) Monera
c) Fungi
d) Plantae
Amoeba belongs to:
a) Monera
b) Fungi
c) Protista
d) Animalia
Which of these has naked seeds?
a) Angiosperms
b) Bryophytes
c) Gymnosperms
d) Thallophytes
Sponges belong to:
a) Coelenterata
b) Porifera
c) Mollusca
d) Annelida
Flatworms belong to:
a) Nematoda
b) Annelida
c) Platyhelminthes
d) Arthropoda
Starfish is a/an:
a) Arthropod
b) Mollusc
c) Echinoderm
d) Chordate
Earthworm belongs to:
a) Nematoda
b) Arthropoda
c) Annelida
d) Mollusca
Plants with no vascular tissues:
a) Pteridophyta
b) Gymnosperm
c) Bryophyta
d) Angiosperm
Which animal has jointed legs?
a) Snail
b) Starfish
c) Earthworm
d) Insect
Fish belongs to which phylum?
a) Echinodermata
b) Chordata
c) Mollusca
d) Arthropoda
Which plant group has flowers?
a) Algae
b) Bryophytes
c) Angiosperms
d) Gymnosperms
Yeast belongs to:
a) Plantae
b) Protista
c) Fungi
d) Monera
Organism without nucleus belongs to:
a) Protista
b) Monera
c) Fungi
d) Plantae
Which phylum has soft body and shell?
a) Arthropoda
b) Mollusca
c) Echinodermata
d) Annelida

✅ Assertion and Reason

A: Gymnosperms have naked seeds.
R: Gymnosperms produce seeds inside fruits.
a) A and R true, R explains A
b) A and R true, R doesn’t explain A
c) A true, R false
d) A false, R true

A: Monera are prokaryotes.
R: They have a well-defined nucleus.
a) A and R true, R explains A
b) A and R true, R doesn’t explain A
c) A true, R false
d) A false, R true

A: Starfish is a chordate.
R: It has a backbone.
a) A and R true, R explains A
b) A and R true, R doesn’t explain A
c) A true, R false
d) A false, R true

A: Arthropods are the largest group of animals.
R: They have jointed legs and segmented body.
a) A and R true, R explains A
b) A and R true, R doesn’t explain A
c) A true, R false
d) A false, R true

A: Angiosperms produce flowers.
R: Flowers help in reproduction.
a) A and R true, R explains A
b) A and R true, R doesn’t explain A
c) A true, R false
d) A false, R true

✅ Case-Based Study

📘 Passage:
A student was studying various plant groups. He saw green slimy algae in a pond. He also saw a moss plant growing on moist soil. He noticed a tall pine tree with cones but no flowers. Later, he found a mango tree with broad leaves and fruits.

Green algae belongs to:
a) Bryophyta
b) Thallophyta
c) Gymnosperm
d) Angiosperm
Moss is part of:
a) Pteridophyta
b) Thallophyta
c) Bryophyta
d) Angiosperm
Pine tree with cones is:
a) Gymnosperm
b) Angiosperm
c) Bryophyta
d) Thallophyta
Which plant group has fruits?
a) Gymnosperm
b) Pteridophyta
c) Angiosperm
d) Thallophyta
Which of these has no roots, stems or leaves?
a) Fern
b) Moss
c) Algae
d) Pine

✅ Reason-Based Questions

Why do we classify organisms?
To study them easily, understand their features, and identify them properly.
Why are Monera called prokaryotes?
Because they have no true nucleus or membrane-bound organelles.
Why are Angiosperms considered advanced plants?
Because they produce flowers and fruits with seeds.
Why is fungi not placed in plant kingdom?
Because fungi are heterotrophic and don’t perform photosynthesis.
Why are algae included in Thallophyta?
Because they lack roots, stems, and leaves.
Why is bacteria kept in Monera?
Because bacteria are unicellular and prokaryotic.
Why are Gymnosperms called “naked seed” plants?
Because their seeds are not enclosed in fruits.
Why are Bryophytes called “amphibians” of plant kingdom?
Because they need water for reproduction and grow in moist areas.
Why is Earthworm placed under Annelida?
Because it has a segmented body.
Why are Arthropods called the most successful animals?
Because they are highly adapted, have jointed legs and exoskeleton.
Why is Hydra placed in Coelenterata?
Because it has a body cavity and tentacles.
Why are echinoderms marine animals?
Because they are found only in oceans and have spiny skin.
Why are mammals placed in phylum Chordata?
Because they have notochord/backbone.
Why are Molluscs soft-bodied animals?
Because they have no skeleton and soft body with a shell.
Why is classification important in biology?
Because it helps to understand the diversity and evolutionary relationships.

✅ Answer Key

MCQs:
1–b, 2–b, 3–c, 4–c, 5–b, 6–c, 7–c, 8–c, 9–c, 10–d, 11–b, 12–c, 13–c, 14–b, 15–b

Assertion & Reason:
16–c, 17–c, 18–d, 19–a, 20–a

Case-Based:
21–b, 22–c, 23–a, 24–c, 25–c