Selina Concise Solutions for ICSE Class 7 Biology Chapter 2 Classification of Plants

Synopsis:

• Classification means grouping things together on the basis of certain common features.
• The classification helps us to identify the living organisms and to study them more easily and systematically.
• The plants can be classified as follows on the basis of their size and shape as:
  1. Herbs
  2. Shrubs
  3. Trees.
• The plants which have soft, green and perishable stems are called herbs. Example: maize, rice, mint etc.
• The plants with woody stems, with branches of almost equal size arising from the stem immediately above the soil are called shrubs. Example: Lemon, jasmine etc.
• The plants which are tall and have hard, woody stems and bear woody branches, twigs and leaves at some distance above the ground are called trees. Example: Coconut and palm.
• Non - flowering plants are called Cryptogams
• Flowering plants are called Phanerogams.
• The non-flowering plants can be further classified as:
  1. Thallophyta (Bacteria, Fungi and Algae)
  2. Bryophyta (Mosses)
  3. Pteridophyta (Ferns)
• Thallophyta do not bear-roots, stems or leaves.
• Mosses have stems and leaves but no roots rather have thread-like structures called rhizoids.
• Mosses are called Amphibians of the plant group as they need water to reproduce.
• Spores are not seeds.
• Spores are tiny structures capable of producing new plants.
• The flowering plants can be further classified into
  1. Gymno sperms.
  2. Angiosperms.
• The flowering plants that bear seeds but no fruit are called Gymnosperms. Their seeds are thin and naked.
• The characteristic feature of gymnosperms is that their roots are well developed, trunk is thick and woody and their leaves are long and pointed.
• The female part of the angiosperms plant is called ovary.
• The plants can be classified on the basis of life span as:
  1. Annuals
  2. Biennials
  3. Perennials
• The plants which live for only one season in a year are called annuals. Example: Wheat, rice, pea, sunflower.
• The plants which complete their life cycle in two years, i.e. in the first year they bear the vegetative parts while in the second year they bear flowers, fruits and seeds are called biennials. Example: Carrot, potato, cabbage.
• The plants which live for more than two years and bear flowers, fruit and seeds every year. [They may even live for hundreds of years] are called perennials. Example: Banyan, pine.
• The perennial plants can be further divided as
  1. Deciduous: Shed their leaves once in a year usually before winter. Example: Oak, mulberry.
  2. Evergreen: These never shed their leaves all at one time. They keep shedding their leaves throughout the year. Example: Mango, guava etc.
• The self - nourishing living beings are called autotrophs. Those nourishing on others are called heterotrophs.
• On the basis of habitat, the plants can be classified as.
  1. mesophytes
  2. xerophytes
  3. hydrophytes.
• Mesophytes : The plants which grow on land and need moderate amount of water for their survival. Example: Mango,apple.
• Xerophytes:
  1. The plants which grow is deserts and need minimum amount of water for their survival.
  2. These have thin and spiny leaves to minimise water loss. Example: Cactus, Babul etc.
• Hydrophytes:
  1. The plants need maximum amount of water and hence grow in water.
  2. They have either very small or no roots at all. Example: Lotus, water lily etc.

Activity 1
Visit a garden park with your teacher or parents and take along with you, a notebook and a pencil. In the park, you would see a large variety of plants some very small, some with average height and some very tall. These plants differ in their features like shape, size (small/medium/tall) and life span. Observe these features carefully (you may even take help from the Gardner) and note down in the table given below. Classify these plants in their respective appearance and categories:

Answer:
1. Name: Mint, Height: Very small, Size: Small, Stem: Green and soft, Category: Herb
2. Name: Jasmine, Height: Medium, Size: Average, Stem: Small and Woody, Category: Shrub
3. Name: Rose, Height: Medium, Size: Average, Stem: Small and woody, Category: Shrub
4. Name: Rice, Height: Small, Size: Small, Stem: Soft and green, Category: Herb
5. Name: Papaya, Height: Tall, Size: Big, Stem: Long and woody, Category: Tree
6. Name: Neem, Height: Tall, Size: Very big, Stem: Thick and woody, Category: Tree
7. Name: Mango, Height: Very tall, Size: Very big, Stem: Thick and woody, Category: Tree
This table helps students identify plants based on their physical structure and growth habits. By observing height and stem texture, you can easily distinguish between herbs, shrubs, and trees in any garden.
Teacher's Tip: Herbs are soft like grass, shrubs are bushy, and trees have a single thick trunk!
Exam Tip: When identifying a shrub, always look for branches starting near the ground level.

Activity 2
Visit a nearby garden or park. Observe the different types of plants small and large, growing there. If permitted by the care-taker collect samples of as many types of plants as you can by plucking. Be sure that you do not damage the plant and collect only one specimen of each type. Take them to your school and record them according to their categories in your notebook

Answer:
1. Category: Flowering plants, Part collected: Flower, Examples: rose, dahlia
2. Category: Non-Flowering plants, Part collected: leaves, Examples: ferns
3. Category: Herbs, Part collected: soft stems, Examples: grass, mint
4. Category: Shrubs, Part collected: woody stem, Examples: china rose, jasmine
5. Category: Trees, Part collected: leaves, Examples: neem, palm
Categorizing collected samples allows students to see the diversity in plant parts like stems and leaves. It reinforces the differences between flowering and non-flowering groups.
Teacher's Tip: Use a scrapbook to dry and preserve your plant samples for a long-lasting collection!
Exam Tip: Be careful to name the correct part collected for each plant category in your record.

Activity 3
You will see two parts in gram seed. Each part of the seed in called cotyledon. In maize seed, you will see only one cotyledon. Can you tell which seed among them is monocotyledon and which is dicotyledon ?
Monocot : Dicot
Answer:
Monocot: maize seed Dicot: gram seed
Monocot seeds like maize have one seed leaf, while dicot seeds like grams can be split into two equal halves. This is a fundamental way to classify higher plants based on their embryonic structure.
Teacher's Tip: Try to split a soaked seed; if it breaks into two neat halves, it is a Dicot!
Exam Tip: Remember "Mono" means one and "Di" means two seed halves.

Review Questions

1.Tick (✓) the appropriate answer :

(i) The two main categories of plants recognised on the basis of whether they produce fruits or not:
a) Biennials and annuals
b) Angiosperms and gymnosperms
c) Herbs and shrubs
d) Bryophyta and pteridophyta
Answer: b) Angiosperms and gymnosperms
Angiosperms are flowering plants that produce seeds inside fruits, whereas gymnosperms produce "naked" seeds without fruit. This classification is based on the protection offered to the developing seed.
Teacher's Tip: Think of "Gym" as open/naked and "Angio" as a vessel or container for the seed.
Exam Tip: Always associate fruit production with the term "Angiosperm."

(ii) Unicellular organisms with a proper nucleus are known as :
(a) Protista
(b) Monera
(c) Fungi
(d) Algae
Answer: (a) Protista
Protista are eukaryotic organisms, meaning they have a well-defined nucleus enclosed in a membrane. Unlike Monera, which are prokaryotic, Protists have complex internal structures within their single cell.
Teacher's Tip: Monera are "Missing" a nucleus, but Protista are "Pro-nucleus" (have one)!
Exam Tip: Remember Amoeba and Paramecium are classic examples of the Protista kingdom.

(iii) Amoeba belongs to :
(a) Monera
(b) Protista
(c) Fungi
(d) Algae
Answer: (b) Protista
Amoeba is a single-celled organism that has a nucleus and other organelles. It is classified under Protista because it is a simple eukaryote that doesn't fit into the plant, animal, or fungal kingdoms perfectly.
Teacher's Tip: Amoeba is a shape-shifter that belongs to the Protista family!
Exam Tip: If a question asks for a unicellular eukaryote, Protista is your go-to answer.

Short Answer Questions

Question 1: Name the categories of the following:

1. Plants which do not have roots, stems, and leaves: Thallophyta.
2. Plants with no roots, but have stems and leaves: Bryophyta or Mosses.
3. Plants with roots, stems, and leaves, and which bear spore- producing bodies: Pteridophyta or Ferns.
4. The amphibians of the plant kingdom mosses (Bryophytes)
Answer: (As identified above)
These categories represent the evolution of plants from simple structures to more complex ones. Thallophyta are the simplest, while Pteridophyta are the most advanced among non-flowering plants.
Teacher's Tip: Think of the hierarchy: No parts (Thallophyta) -> No roots (Bryophyta) -> All parts with spores (Pteridophyta).
Exam Tip: Make sure to mention "rhizoids" if asked why Bryophytes have no true roots.

Question 2: Give two characterists and one example of each of the following:

(i) Algae:
Answer: Example: Spirogyra
(a) these are found in stagnant water of ponds, growing as green scum
(b) they have chlorophyll
Algae are simple thallophytes that perform photosynthesis using their chlorophyll. They are usually found in aquatic environments and lack complex organs like roots or flowers.
Teacher's Tip: Algae are the "green blankets" you see on top of pond water!
Exam Tip: Mentioning "chlorophyll" is essential because it explains how they make their own food.

(ii) Fungi:
Answer: Example: Mushroom
(a) They cannot prepare their food
(b) Most fungi live on dead and decaying organic matter
Fungi are heterotrophic organisms that absorb nutrients from their surroundings. Since they lack chlorophyll, they cannot produce food through photosynthesis like plants do.
Teacher's Tip: Fungi are the "recyclers" of nature, breaking down dead stuff!
Exam Tip: Do not classify fungi as plants; they belong to a completely separate kingdom.

(iii) Monocot:
Answer: Example: Maize
(a) They have seeds with one cotyledon
(b) Cotyledon usually becomes the embryonic first leaves of a seedling
Monocots generally have parallel leaf venation and fibrous roots. Their seeds do not split into two halves, which is their most defining characteristic.
Teacher's Tip: Grass and grains like rice and wheat are almost always Monocots!
Exam Tip: If you forget the example, think of any grain that has "long, thin" leaves.

(iv) Dicot
Answer: (a) They contain two cotyledons in their seed.
(b) They have network like (reticulate) venation in their leaves.
Examples : gram, rose, mango.
Dicots are advanced flowering plants characterized by seeds with two storage leaves. They often have taproots and broad leaves with branching veins.
Teacher's Tip: If a leaf has a "net" of veins, it's a Dicot!
Exam Tip: Using the term "reticulate venation" earns you high marks in leaf description.

(v) Bryophyta
Answer: (a) They have stems and leaves but no roots.
(b) They are non-flowering plants.
Examples : mosses, liverworts.
Bryophytes are small, green plants that usually grow in carpets in moist areas. They absorb water through their entire body surface rather than using complex vascular systems.
Teacher's Tip: Bryophytes are the "Mossy carpets" in damp forests!
Exam Tip: Always specify that they lack "true" roots and use rhizoids instead.

(vi) Pteridophyta
Answer: (a) They are non-flowering plants i.e. do not produce flowers are seeds. They reproduce through spores
(b) They have feather like leaves divided into leaflets. Example : ferns
Pteridophytes are the first land plants to have a proper vascular system for transporting water. They grow best in cool, damp, and shady environments.
Teacher's Tip: Ferns look like "feathers" sticking out of the ground!
Exam Tip: Mentioning "reproduction through spores" is a key feature of this group.

(vii) Thallophytes
Answer: (a) These plants do not have roots, stems or leaves.
(b) They are non-flowering plants.
Examples : Bacteria, fungi, algae
Thallophytes have a simple body called a thallus that isn't divided into organs. They are the most primitive group in the plant classification system.
Teacher's Tip: Thallophyta = No Shape, just a "mass" of cells!
Exam Tip: Use the word "undifferentiated" to describe their body structure.

3. Differentiate between

(i) Algae and fungi
Answer:
Algae
1. Usually green having chlorophyll
2. Found in stagnant water of ponds.
3. Are usually Autotrophs e.g. Spirogyra
Fungi
1. Do not have chlorophyll
2. Found on dead and decaying organic matter.
3. Are usually saprophytes. e.g. Bread mould
Algae can make their own food through photosynthesis because they have green pigment. Fungi must live on other things because they lack this pigment and cannot use sunlight.
Teacher's Tip: Algae = Green Producers; Fungi = Non-green Recyclers!
Exam Tip: Use the term "autotrophic" for algae and "heterotrophic" or "saprophytic" for fungi.

(ii) Monocot and dicot plants.
Answer:
Monocot
The plants which contain only one cotyledon in their seeds.
example: Grass, Maize
Dicot
The plants which contain two cotyledons in their seeds.
example: Brinjal, Mango
The main difference lies in the number of seed leaves inside the embryo. This single difference leads to many other variations in roots, leaves, and flowers.
Teacher's Tip: "Mono" is one, "Di" is two. Count the cotyledons!
Exam Tip: Always provide a clear example for both types when differentiating.

(iii) Autotrophs and heterotrophs
Answer:
Autotrophs
1. They can make their own food using solar energy.
2. These include green plants having chlorophyll.
3. They are also called producers.
Heterotrophs
1. They cannot make their own food and depend on autotrophs or other heterotrophs for food.
2. These include animals and non-green plants.
3. They are also called consumers.
Autotrophs are the starting point of any food chain because they capture energy from the sun. Heterotrophs must eat these plants or other animals to get the energy they need to live.
Teacher's Tip: Auto = Self (makes own food); Hetero = Different (eats others)!
Exam Tip: Mentioning "chlorophyll" and "producers/consumers" adds detail to your answer.

(iv) bacteria and amoeba
Answer:
Bacteria
1. Bacteria are one of the smallest and structurally the simplest organisms.
2. Bacteria are unicellular cells
3. They are found every-where air, water, soil, the bodies of humans, plants and animals.
4. They are visible only under a high powered light microscope
Amoeba
1. Amoeba is one of the simplest animals.
2. It is made up of just one single cell.
3. Amoeba is found in ponds, ditches and other places with stagnating water.
4. They can be seen under the microscope only
Bacteria are prokaryotic and found literally everywhere on Earth. Amoeba are eukaryotic and generally prefer aquatic environments where they can move freely.
Teacher's Tip: Bacteria are tiny dots; Amoeba are blobby single-celled animals!
Exam Tip: Remember that Bacteria belong to kingdom Monera and Amoeba belongs to Protista.

(v) mosses and ferns
Answer:
mosses
1. Mosses grow as green, velvety layers in moist places such as damp soil, on the bark of trees, and on damp walls.
2. These plants have stems and leaves, but no roots
ferns
1. Ferns are grown in most of the gardens for their beautiful leaves.
2. They bear well-formed leaves, stems and roots.
Mosses are very simple and carpet-like, lacking true roots. Ferns are more complex, having a vascular system and true roots, which allows them to grow larger.
Teacher's Tip: Mosses are "rootless carpets" while ferns are "feather-leaved bushes"!
Exam Tip: Note that both reproduce via spores, but ferns have "true roots."

(vi) Angiosperms and gymnosperms
Answer:
Angiosperms
1. These plants bear seeds inside a fruit.
2. Leaves are usually broad.
3. They usually shed their leaves every autumn.
4. Examples: rose, sunflower, sugarcane.
gymnosperms
1. These plants bear naked seeds called cones. Fruit is absent.
2. Leaves are usually needle like. They usually remain green throughout the year.
Examples: Pine, cedar, fir.
Angiosperms hide their seeds inside yummy fruits to attract animals for dispersal. Gymnosperms leave their seeds exposed on woody cones and often keep their needle-like leaves all year.
Teacher's Tip: Angiosperms = Fruit "Vessels"; Gymnosperms = "Naked" Cones!
Exam Tip: Always mention "fruit" for Angiosperms and "cones" for Gymnosperms.

Long Answer Questions

Question 1: What name is given to bacteria found in the root nodules of pea plants ? State their importance.
Answer:
Rhizobium bacteria are found living in the root nodules (small swollen structures on roots) of leguminous plants like the pea, bean etc. These bacteria trap the nitrogen from the atmosphere and convert it into nitrates (mineral salts) which can be easily absorbed by the plants from the soil along with the water. It is observed here that the bacteria provide food to the host plant and the host plant in turn provides shelter for the bacteria. This kind of relationship wherein two organisms live in harmony each benefiting from such a relationship is called symbiosis. The organisms are called symbionts.
Rhizobium acts as a natural fertilizer factory for pea plants by fixing nitrogen from the air. In return, the plant gives the bacteria a safe home and sugars to eat.
Teacher's Tip: Rhizobium = "Root-Roommate" that pays rent with nitrogen!
Exam Tip: Use the term "nitrogen fixation" to describe exactly what these bacteria do.

Question 2: Briefly explain four types of bacteria on basis of their shape.
Answer:
There are four common forms of bacteria - coccus, bacillus, spirillum and vibrio.
1. Coccus form: These bacteria are spherical or ovoid in shape.
2. Bacillus form (bacillus : rod) These are rod-shaped. These may also occur singly or in group of two's or three's, joined end to end in long chains.
3. Spirillum form: These are spiral-shaped.
4. Vibrio form: These are short, curved, appearing comma- shaped. Chloera bacteria (Vibrio cholerae) are of vibrio type.
Bacteria are classified primarily by how they look under a microscope. Each shape often corresponds to different ways they move or interact with their environment.
Teacher's Tip: Coccus = Circle; Bacillus = Bar (rod); Spirillum = Spiral; Vibrio = Comma!
Exam Tip: Draw small diagrams next to each name to help the examiner see you know the shapes.

Question 3: Give reasons for the following:
(i) Bryophytes are called amphibians of plant kingdom.
(ii) Amoeba does not have any regular shape.
Answer:
1. Since bryophytes grow on land but need water for reproduction (like frogs in animals), they are called the amphibians of plant kingdom.
2. The body of Amoeba is irregular in shape. The outer covering of the body is the cell membrane. A prominent nucleus lies in the center surrounded by cytoplasm.
Bryophytes are tied to wet areas because their sperm must swim through water to reach eggs. Amoeba lacks a stiff cell wall, which allows its cell membrane to flow and change shape constantly.
Teacher's Tip: Think of Bryophytes as "frog-plants" because they love damp spots!
Exam Tip: For Amoeba, mention "pseudopodia" if you know it, as that is how they change shape.

Question 4: What is a contractile vacoule ? State its function in amoeba.
Answer:
Excess of water from the body of the amoeba is collected in the contractile vacuole. Ammonia is soluble in water. Hence, sometimes ammonia is expelled out along with the water from the contractile vacuole.
Function: The contractile vacuole expands when there is water in it and shrinks when the water is released into the surrounding.
This organelle acts like a tiny pump to prevent the Amoeba from bursting by taking in too much water. It also helps the cell get rid of liquid waste products like ammonia.
Teacher's Tip: Think of it as a "bilge pump" on a boat!
Exam Tip: Clearly state that its primary job is "osmoregulation" or water balance.

Question 5: List out Jive uses each of bacteria and fungi in our lives.
Answer:
The uses of Bacteria are :

• Lactobacilus bacteria is used for curdling of milk (formation of curd from milk). It converts the milk sugar (lactose) into lactic acid, giving the sour taste to the curd.
• Certain bacteria like Acetobacter ferment fruit juices into vinegar (acetic acid).
• Tanning of leather: Certain bacteria are used in curing of animal hides and skin.
• Retting of fibres: Jute fibres are separated and made softer by the use of bacteria.
• Formation of compost and manure: Cow dung, horse dung and agricultural wastes are subjected to bacterial action which causes their decay and produce very useful manure.

The uses of Fungi are:

• Fungi are an important source of food. Some mushrooms such as Morechella and Agaricus are edible.
• Yeast, a unicellular fungus, is important in bakeries as it is used in the making of bread. It is also important in the breweries for making alcohol.
• Yeast also produces vitamin B.
• Fungi, like bacteria, are also good decomposes. They decompose dead organic matter and return the nutrients back into the soil.
• Penicillin an important antibiotic is obtained from a fungus called Penicillium notatum.
• Both bacteria and fungi are essential for the food industry and for recycling nutrients in the environment. They also provide us with medicine and help in processing materials like leather and fiber.

Teacher's Tip: Bacteria make the curd, and Fungi make the bread - they are our "kitchen helpers"!
Exam Tip: Mention the specific name "Penicillium" when talking about medicine for extra points.

PRACTICE QUESTIONS

A. Select the most appropriate answer.

1. An example of a flowering plant is
a. fern.
b. yeast.
c. Spirogyra.
d. rice.
Answer: d. rice.
Rice is a cereal grain and a flowering plant that produces seeds after blooming. Ferns, yeast, and Spirogyra belong to non-flowering groups.
Teacher's Tip: Most of our major food crops (wheat, rice, maize) are flowering plants!
Exam Tip: Don't be fooled by the size; even small grasses have tiny flowers.

2. Well-developed roots, stem and leaves are present in
a. bryophytes and algae.
b. algae, bryophytes and angiosperms.
c. algae, bryophytes andgymnosperms.
d. ferns, gymnosperms and angiosperms.
Answer: d. ferns, gymnosperms and angiosperms.
These groups have advanced vascular systems and true organs for growth on land. Algae and bryophytes are simpler and lack these well-defined parts.
Teacher's Tip: Remember: Higher plants = Proper parts!
Exam Tip: If the list includes "Algae," it cannot be the group with "well-developed" roots.

3. Biennials complete their life cycle in
a. two years.
b. one year.
c. three years.
d.ten years.
Answer: a. two years.
The first year is for growing roots and leaves, while the second year is for flowers and seeds. After producing seeds in the second year, the plant usually dies.
Teacher's Tip: "Bi" always means two, like a bicycle has two wheels!
Exam Tip: Note that "growing" happens in year 1 and "reproduction" in year 2.

4. Plants that grow and thrive in water are called
a. mesophytes.
b. hydrophytes.
c. xerophytes.
d. none of these
Answer: b. hydrophytes.
"Hydro" refers to water, and these plants have special adaptations like spongy stems to float. They often have very small or no roots because they are surrounded by water.
Teacher's Tip: Hydro = Water; Phyte = Plant. Water-plant!
Exam Tip: Lotus and Water Lily are the most common examples to remember.

5. Parasites and saprophytes belong to group
a. autotrophs.
b. xerophytes.
c. heterotrophs.
d. mesophytes.
Answer: c. heterotrophs.
Since they cannot make their own food, they must get nutrition from other living things (parasites) or dead matter (saprophytes). They rely entirely on external sources for energy.
Teacher's Tip: If they don't have green chlorophyll, they must be heterotrophs!
Exam Tip: Know that "Saprophyte" specifically means eating "rotten" things.

B. Fill in the blanks.

1. Algae are green plants that contain chlorophyll and usually live in stagnant water.
2. The leaves of ferns are called fronds.
3. In gymnosperms, the seeds are not enclosed in a fruit.
4. Cuscuta is a parasitic plant.
Answer: (As filled above)
These blanks highlight key vocabulary and unique names for plant parts. Knowing these terms helps in identifying specific plant groups accurately.
Teacher's Tip: A "Frond" is just a fancy word for a fern leaf!
Exam Tip: Spelling counts for scientific terms like "Gymnosperms" and "Fronds."

C. State if the following statements are true or false. Correct the statement if it is false.

1. Bryophytes grow in dry areas.
Answer: False: Bryophytes grow in moist areas.

2. Pteridophytes grow in damp and shady areas.
Answer: True.

3. Plants that have seeds in cones are called ferns.
Answer: False: Plants that have seeds in cones are called gymnosperms.

4. Dicotyledonous plants have seeds with two cotyledons
Answer: True.

5. Perennial plants continue to grow and produce seeds every year.
Answer: True.
(As corrected above)
Correcting these statements helps clarify where plants live and how they produce offspring. Most non-flowering plants need dampness, while advanced perennials can survive many years.
Teacher's Tip: Ferns don't have seeds (they have spores), but Gymnosperms have seeds in cones!
Exam Tip: Always write out the full correct sentence for false statements to get full credit.

D. Differentiate between

Question 1: gymnosperms and angiosperms

Answer:
Gymnosperms
1. These plants bear naked seeds called cones.
2. They usually have needle like leaves.
3. They usually remain green throughout the year.
4. e.g. Pine, Cycas cedar.
Angiosperms
1. These plants bear seeds enclosed inside a fruit.
2. They usually have normal flat leaves.
3. They usually shed then- leaves every autumn.
4. e.g. Rose, apple, mango.
The main difference is the "seed protection" - naked in cones versus hidden in fruits. Their leaves also differ significantly, with gymnosperms often being "evergreen" and angiosperms being "deciduous."
Teacher's Tip: Angiosperms = Flowers & Fruit; Gymnosperms = Cones & Needles!
Exam Tip: Use "naked seeds" and "seeds enclosed in fruit" as your first point of difference.

Question 2: annuals and perennials
Answer:
Annuals
1. These plants complete their life cycle in one year.
2. These plants germinate, flower and produce seeds within a season.
3. e.g. Maize, wheat, rice.
Perennials
1. These plants live for many years.
2. They continue to grow and produce flowers for many years.
3. e.g. Mango, banyan, neem.
Annuals are short-lived and must be replanted every year from seeds. Perennials are long-lived and become permanent parts of the landscape, flowering again and again.
Teacher's Tip: Perennial = "Permanent" (they stay year after year)!
Exam Tip: Note that "Annual" refers to one year/season only.

Question 3: xerophytes and hydrophytes
Answer:
Xerophytes
1. These are plants that grow on dry land like deserts where there is scarcity of water.
2. Leaves are reduced to spines to minimise the loss of water.
3. Roots are long and reach deep layers of the soil.
4. e.g. Cactus, babul
Hydrophytes
1. These plants need maximum water to grow and hence live in water.
2. Leaves have a waxy coating to protect themselves from water.
3. Roots are very reduced as water is available in plenty.
4. e.g. Hydrilla, lotus.
Xerophytes are built to "save" water in harsh deserts. Hydrophytes are built to "survive" in excess water where they might otherwise rot or drown.
Teacher's Tip: Xerophyte = "Zero" water (almost); Hydrophyte = "Highly" watered!
Exam Tip: Mention "spines" for xerophytes and "waxy coating" for hydrophytes as adaptations.

Question 4: flowering plants and non-flowering plants
Answer:
Flowering plants
1. Flowering plants bear seeds and fruits.
2. They are also called as phanerogams.
3. They are further divided into gymnosperms and angiosperms.
4. e.g. Mango plant, wheat plant.
Non-flowering plants
1. Non-flowering plants do not produce flowers and seeds.
2. They are also called as cryptogams.
3. They are further divided into Bryophyta, Thallophyta and Pteridophyta
4. e.g. Ferns, mosses, mushroom.
Flowering plants use seeds for reproduction and are generally more complex. Non-flowering plants use spores and are often simpler in structure.
Teacher's Tip: Phanerogams = "Visible" reproduction (seeds); Cryptogams = "Hidden" (spores)!
Exam Tip: Grouping them as Cryptogams and Phanerogams shows a higher level of scientific knowledge.

E. Write short answers to the following questions.

Question 1: What are cryptogams ?
Answer:
Cryptogams are non-flowering plants which do not produce seeds and flowers. They are further categorised into Thallphyta (Algae, Bacteria, Fungi), Bryophyta (Mosses) and Pteridophyrta (Ferns).
These plants reproduce using spores instead of seeds and are usually found in moist environments. They represent the "hidden" reproductive group of the plant world.
Teacher's Tip: Think of "Crypto" as "Hidden" - they hide their seeds (because they don't have any)!
Exam Tip: Name at least two groups (like algae and ferns) to make your answer complete.

Question 2: State the groups into which plants are classified on the basis of seed-bearing nature.
Answer:
1. Seed bearing plants are called phanerogams.
2. Non-seed bearing plants are called cryptogams.
Seed-bearing plants represent the more evolved species that produce fruits or cones. Non-seed bearing plants are more primitive and use tiny spores to make new plants.
Teacher's Tip: Seeds are for Phanerogams; Spores are for Cryptogams!
Exam Tip: Be clear that "seed-bearing" is the main dividing line here.

Question 3: What are bryophytes ?
Answer:
Bryophytes are those non-flowering plants which grow on moist land and need water to reproduce. They are also called the amphibians of the Plant Kingdom, e.g. Mosses, liverworts.
They are small, green, and lack true vascular tissues for moving water. Because they don't have true roots, they absorb water directly from their surroundings.
Teacher's Tip: Bryophytes = The damp "Green Fuzz" on walls!
Exam Tip: "Amphibians of the Plant Kingdom" is the most important phrase to include.

Question 4: What are characteristics of pteridophytes ?
Answer:
Characteristics of pteridophytes (ferns) are :
1. These are non-flowering plants which do not produce seeds.
2. These plants grow in damp and shady areas.
3. The leaves are feather like and called fronds. (Pteron means feather and phyton means plants). They are divided into leaflets.
4. They reproduce through spores bom on the lower side of fronds in small rounded brown structures called sori.
5. The plants either have underground stems called rhizome or stems above the ground.
Pteridophytes are advanced non-flowering plants that have true roots and stems. Their unique "sori" (spore dots) on the back of leaves are a very easy way to identify them.
Teacher's Tip: Look for the "brown dots" on the back of a fern leaf - those are the sori!
Exam Tip: Using the word "fronds" correctly shows you know your botanical terms.

Question 5: Give two important features of angiosperms.
Answer:
Two important features of angiosperms are:
1. They are plants with well-developed roots, stem, leaves and flowers.
2. They produce seeds which are enclosed in a fruit.
Angiosperms are the most dominant plants on Earth today because of their efficient reproduction. Their flowers attract pollinators, and their fruits help spread their seeds far and wide.
Teacher's Tip: Almost every fruit you eat comes from an Angiosperm!
Exam Tip: "Enclosed seeds" is the absolute key feature to mention.

Question 6: What is the basis of classification of plants into flowering plants and non-flowring plants ?
Answer:
The presence or absence of flowers and seeds in a plant forms the basis of classification of plants into flowering plants (Phanerogams) and non-flowering plants (Cryptogams).
This is one of the biggest divisions in the plant kingdom. It tells us whether a plant reproduces with complex flowers and seeds or simple spores.
Teacher's Tip: Look for the bloom - if it flowers, it's a Phanerogam!
Exam Tip: Use the Greek names (Cryptogams/Phanerogams) to strengthen your answer.

Question 7: Why bryophytes are called amphibians of plant kingdom?
Answer:
Since bryophytes grow on land but need water for reproduction (like frogs in animals), they are called the amphibians of plant kingdom.
They occupy a middle ground between water-dwelling algae and fully land-dwelling vascular plants. Their life cycle depends on moisture for the sperm to swim and fertilize eggs.
Teacher's Tip: Just like a frog, they need land to live but water for their "babies"!
Exam Tip: Mention "external water for fertilization" to be very specific.

F. Answer the following in detail.

Question 1: How are monocots different from each other ? Explain giving examples.
Answer:
Monocots
1. The angiosperms whose seeds have only one part or cotyledon are called an monocots.
2. e.g. Wheat, maize.
Dicots
1. The angiosperms whose seeds have two parts or 02 cotyledons are called dicots.
2. e.g. Pea, bean.
The differences go beyond the seed: monocots have leaves with parallel veins, while dicots have veins that form a network. Monocots also typically have fibrous roots compared to the thick taproots of dicots.
Teacher's Tip: Split a pea and a corn kernel to see the difference yourself!
Exam Tip: A comparative table is the best way to answer "How are they different."

Question 2: Classify plants on the basis of (i) habitats in which they live, and (ii) time taken to complete their life cycle.
Answer:
(i) On the basis of a place where a plant grows (its habitat), plants are classified into three groups :
1. Mesophytes: Plants which grow on land and need moderate amount of water, e.g. Potato, tomato.
2. Hydrophytes: Plants that need maximum water to grow and hence live in water. They may be floating or partially/completely submerged. e. g. Lotus, Hydrilla.
3. Xerophytes: Plants that grow on dry land like deserts and need minimum amount of water to live. They have thin and spiny leaves to reduce water loss. e.g. Cactus, babul.
(ii) On the basis of time taken to complete their life cycle, plants are divided into three groups :
1. Annuals: These plants complete their life cycle in one season in a year. e.g. Wheat, rice.
2. Biennials: These plants complete their life cycle in two years i.e. in the first year, they bear root, stem and leaves and in the second year, they produce flowers, fruits and seeds. e.g. Carrot, radish, turnip.
3. Perennials: These plants live for more than two years and bear flowers, fruits and seeds every year. e.g. Mango, Banyan.
These classifications help us understand how plants adapt to their environment and how long they will live. Knowing habitat helps in gardening, while knowing life cycles helps in farming.
Teacher's Tip: Use "X" for Xerophyte = "Extra Dry"!
Exam Tip: Ensure you group your answer under headings (i) and (ii) as asked in the question.

Question 3: Write a short note on gymnosperms.
Answer:
Gymnosperms are plants having naked seeds, i.e., seeds are not enclosed in fruits. The seeds are borne on woody structures called cones, and hence called conifers or coniferous trees. They produce male and female cones for reproduction instead of flowers. Gymnosperms are mostly tall trees growing on mountains. They have well developed roots, thick and woody stems and long needle-shaped leaves. They are evergreen plants. Examples : Pine, cycas, cedar, Ginkgo, spruce, etc.
Gymnosperms are the "cone-bearers" that often dominate high, cold mountain forests. Their needle-like leaves help them shed snow easily and prevent water loss in dry, cold air.
Teacher's Tip: "Naked seeds" simply means there is no fruit around them!
Exam Tip: Mention "evergreen" and "needle-shaped leaves" as important survival features.

Question 4: How are the herbs, shrubs and trees different ? Give examples.
Answer:
Depending on the size, plants are classified into three groups:
1. Herbs: They are very small plants with soft and green stems. Eg. Mint, spinach.
2. Shrubs: They are medium sized plants with woody stems. The branches are almost same size arising from the stem immediately above the soil. e.g. Rose, jasmine.
3. Trees: Tall plants with a thick, hard and woody stem are called trees. They bear woody branches and leaves at some distance above the ground. e.g. Coconut, mango.
This classification is based purely on physical appearance and stem texture. Trees have one main trunk, shrubs are bushy with many stems, and herbs are small and tender.
Teacher's Tip: If you can snap the stem easily, it's probably a herb!
Exam Tip: Distinguish shrubs by saying their branches start "near the ground."

G. Classify the given plants into different categories that are indicated.

Question 1: Cedar, neem, banana, pine, Cycas, marigold, Petunia, Juniper, fig, orange, Ginkgo into gymnosperms and angiosperms.
Answer:
Gymnosperms: Cedar, pine, Cycas, juniper, Ginkgo.
Angiosperms: Neem, banana, Marigold, Petunia, Fig, orange.
Gymnosperms generally include needle-leaved trees like pine, while Angiosperms include almost all common flowers and fruit trees. This division is based on seed and flower structure.
Teacher's Tip: Most large shade trees in your yard are Angiosperms, but Christmas trees are Gymnosperms!
Exam Tip: Cycas and Ginkgo are special gymnosperms that often appear in tests.

Question 2: Hydrilla, Opuntia, babul, rose, water lily, lotus, Vallisneria into mesophytes, hydrophytes, xerophytes.
Answer:
Mesophyte: Rose.
Hydrophytes: Hydrilla, Water lily, Lotus, Vallisneria.
Xerophytes: Babul, Opuntia.
This exercise tests your knowledge of plant habitats. Hydrophytes live in water, Xerophytes live in deserts, and Mesophytes live on regular land.
Teacher's Tip: Opuntia is a cactus - it loves the desert!
Exam Tip: Remember Hydrilla is a submerged hydrophyte, while Lotus floats.

Question 3: Eucalyptus, mint, rose, spinach, neem, radish, tulsi, banana and china rose into herbs, shrubs and trees.
Answer:
Herbs: Mint, Spinach, Radish, Tulsi.
Shrubs: Rose, China rose.
Trees: Eucalyptus, Neem, Banana.
Classification depends on the height and the "woodiness" of the stem. Even though a banana plant looks big, it is classified as a "tree" here due to its size, though botanically it is a giant herb!
Teacher's Tip: Tulsi and Mint are classic kitchen herbs!
Exam Tip: Be careful with "Banana"; in this school classification, it is grouped with trees due to its height.

Question 4: Mango, carrot, poppy, apple, oak, mint, cabbage, radish and turnip into annuals, biennials and perennials.
Answer:
Annuals: (Example Wheat/Rice from text - none in this list explicitly, but Poppy/Mint can behave as annuals in some climates).
Biennials: Carrot, Cabbage, Radish, Turnip.
Perennials: Mango, Poppy, Apple, oak, Mint.
Root vegetables like carrots and radishes are famous biennials because they store food in their roots during the first year. Trees like Mango and Oak can live for many decades as perennials.
Teacher's Tip: If it grows in a vegetable patch and you pull the root, it's often a biennial!
Exam Tip: Group all the edible roots (carrot/radish/turnip) together as biennials.