CBSE Class 9 Biology Practicals Worksheet

Experiment 3

AIM
To study the external features (morphology) of root, stem, leaf and flower of monocot and dicot plants.

MATERIALS REQUIRED
Fresh specimen or preserved specimens of monocot plant-onion plant and dicot plant-mustard plant.

PROCEDURE
(a) External features of monocot plant

How to do it:
1. Take the onion plant on the table and carefully observe the features of different organs.
2. Compare the features of specimen with the features given below:

Features:
1. Root: The roots are in a cluster. These roots arise from the base of the onion bulb. The roots are fibrous and are hair-like in structure.
2. Stem: The stem in onion plant is modified am. It is disc-like. It is enclosed by the scale leaves. It grows from a bulb. Stem is underground.
3. Leaves: Leaves are long, cylindrical, green, hollow from inside. The leaves have parallel venation.
4. Flower: Flower is complete, bracts are present, while coloured and completely.
5. Perianth (male whorl): It has 6 stamen arranged in 2 whorls of 3 each. Androyceum (male whorl); 6 stamen and Gynoecium (female whorl); Style is short, and stigma is short.
Note: Whole plant is eater as vegetable.

(b) External features of dicot plant

How to do it:
1. Keep the specimen on the table and carefully observe the features of different organs.
2. Compare the features of specimen with the features given row.

VIVA VOCE QUESTIONS

Question 1. What is the study of external features of organisms called?
Answer: Morphology.
In simple words: Morphology is the study of the external structure and form of living organisms.

Exam Tip: Remember that anatomy deals with internal structures, while morphology deals with external features.

Question 2. How are monocot plant roots different from dicot plant roots?
Answer: Monocot plant roots are in cluster and fibrous. Dicot plant roots have a tap root system with lateral branches.
In simple words: Monocots have bushy fibrous roots, whereas dicots have one main long taproot.

Exam Tip: Use keywords like "fibrous" for monocots and "tap root" for dicots to score full marks.

Question 3. Name venation of dicot leaves.
Answer: Reticulate venation.
In simple words: Dicot leaves have a net-like web of veins.

Exam Tip: Always associate reticulate venation with dicots and parallel venation with monocots.

Question 4. How many cotyledons does a rice seed have?
Answer: One cotyledon (Monocot).
In simple words: Rice is a monocot, so its seed contains only one seed leaf.

Exam Tip: Rice, wheat, and maize are classic examples of monocots with one cotyledon.

Question 5. If a leaf has parallel venation, it is a leaf of .......... plant.
Answer: Monocot.
In simple words: Parallel veins running side by side indicate a monocot plant.

Exam Tip: This is a direct diagnostic feature used to identify plant groups in practical exams.

Question 6. Why a grass plant is monocot?
Answer: Because it has parallel venation in leaves, fibrous roots, and seeds with a single cotyledon.
In simple words: Grass shares all the key anatomical features typical of monocotyledonous plants.

Question 7. Shankhank collected two cotyledonous seeds, one of those is incorrect find out. Rice, Pea, Bean, Tamarind
Answer: Rice.
In simple words: Rice is a monocot seed, while pea, bean, and tamarind are dicot seeds with two cotyledons.

Exam Tip: Rice is a cereal grain and belongs to monocotyledons, unlike pulses and legumes.

Question 8. What does the term angiosperm mean?
Answer: Angio-enclosed, sperm-seed. Seed enclosed inside the fruit.
In simple words: Angiosperms are flowering plants that produce enclosed seeds within a fruit.

Question 9. The leaves of onion are ..........
Answer: Green, cylindrical and hollow.
In simple words: Onion leaves are tube-like and filled with air spaces inside.

Exam Tip: Note this special modification in onion leaves compared to flat foliage leaves.

Question 10. Which type of stem is found in onion plant?
Answer: Underground, disc shaped.
In simple words: The stem is reduced to a flat disc beneath the ground surrounded by fleshy scales.

Exam Tip: Identify the bulb structure clearly as a modified underground stem.

Multiple Choice Questions

Question 1. Student has listed following features of a plant. Which feature is incorrect about the plant?
(i) It has a tap root system.
(ii) Leaves are long, ribbon shaped.
The correct features of a plant:
(i) The root is tap root system.
(ii) Broad leaves, reticulate venation.
(iii) Strong stem.
Which type of plant it is?
(a) Dicot
(b) Monocyl. and dicot
(c) Monocot and dicot.
(d) Monocot.
Answer: (a) Dicot
Tap roots and reticulate venation are characteristic features of dicotyledonous plants.
In simple words: Features like taproots and broad leaves with a network of veins belong strictly to dicots.

Exam Tip: Look for contrasting features like taproot vs fibrous root to instantly classify plants.

Question 2. These are drawing of leaves of plants. Which leaf belongs to monocot plant?
(1) Parallel venation leaf
(2) Reticulate leaf
(3) Reticulate leaf
(4) Reticulate leaf
Answer: (a) (1)
Leaf (1) exhibits parallel venation which is the distinct feature of monocot plants.
In simple words: Only leaf number 1 shows parallel veins, which identifies it as a monocot.

Exam Tip: Always examine venation patterns in diagrams before answering plant identification questions.

Question 3. There are four seeds of same plants. One seed is root of same category. Identify it.
1. Gram
2. Pea
3. Maize
4. Bean
Answer: (c) 3
Maize is a monocot seed, whereas gram, pea, and bean are dicot seeds.
In simple words: Maize is different because it is a monocot grain among dicot pulses.

Exam Tip: Group seeds into cereals (monocots) and pulses/legumes (dicots) for quick identification.

Question 4. Which student has labelled the figure correctly?
1. Swati (Root, Stem, Scale Leaves)
2. Suman (Root, Stem, Leaf)
3. Shikha (Roots, Leaves, Stem)
4. Shankhank (Root, Stem, Leaf)
Answer: (b) 2
Suman has accurately labelled the root, stem, and leaves of the plant specimen.
In simple words: Student 2 correctly pointed out all three vegetative plant organs.

Exam Tip: Carefully verify label pointers in botanical diagrams to avoid minor mistakes.

Experiment 4

AIM
To study the life cycle of mosquito.
MATERIALS REQUIRED
Preserved specimen of life cycle of mosquito.
OR
Chart showing life cycle of mosquito.

LIFE CYCLE
1. Adult Mosquito: The mosquitoes male and female copulate in air while flying.
2. Eggs of Anopheles: Laying of eggs is laid in standing water, in pools, puddle, well, ditch, water tank, coolers, etc.
3. Eggs of Culex: Mosquitoes is laid in clusters of 150 - 500 eggs. It is called 'raft'. Eggs are cigar shaped.
4. Larva: The larva is called wriggler. The eggs are black and with air float on the sides.
5. Pupa: After the four moults larva sinks to the bottom and takes comma shape. It is called pupa. Culex pupa is greyish, coloured and anopheles pupa is greenish grey.
6. Imago: Young mosquito, does not have mouth and anus. It depends on the stored food. This stage lasts up to 2-7 days.
7. Imago. Young mosquito, to called imago. It comes out after hatching of pupa. It takes about one month for the complete life cycle, from egg to imago stage. It starts reproduction after a week of hatching.
8. Lifespan of mosquito is 3 weeks. It generally dies after copulation. Female mosquitoes live for one to many months till they keep laying eggs.

VIVA VOCE QUESTIONS

Question 1. Name the mosquito that causes malaria.
Answer: Anopheles (Female)
In simple words: Malaria is transmitted exclusively by the bite of infected female Anopheles mosquitoes.

Exam Tip: Always specify "Female Anopheles" since male mosquitoes feed only on plant nectar and do not bite humans.

Question 2. How are the eggs of anopheles mosquito different from culex eggs?
Answer: Anopheles eggs are boat-shaped and float singly on the water surface with lateral floats. Culex eggs are cigar-shaped and laid vertically in clusters called rafts.
In simple words: Anopheles eggs float individually with side floats, while culex eggs are glued together into floating rafts.

Exam Tip: Contrast "single with lateral floats" against "vertical clusters/rafts" for full credit.

Question 3. Are the eggs of anopheles laid in raft?
Answer: No, they are laid singly on the water surface.
In simple words: Anopheles eggs do not form rafts; they float separately on the water.

Question 4. What is position of anopheles larva in water?
Answer: Horizontal to water surface.
In simple words: The larva lies parallel to the water surface to breathe through its spiracles.

Question 5. How can we identify the culex eggs from that of anopheles?
Answer: Culex eggs are laid in clusters that appear like a raft, whereas anopheles eggs are laid singly with side floats.
In simple words: Culex eggs stick together in rafts, while Anopheles eggs float alone.

Exam Tip: Use the presence of rafts as the primary diagnostic difference.

Question 6. What is position of culex larva in water?
Answer: Its at \(45^{\circ}\) in position of culex larva in water?
In simple words: Culex larvae hang head down at an angle of \(45^{\circ}\) to the water surface.

Question 7. How many eggs does the female culex mosquito lay at one time?
Answer: 150 - 200 eggs.
In simple words: A single female Culex lays about 150 to 200 eggs per batch.

Exam Tip: State the exact numerical range 150-200 for accuracy.

Question 8. Which mosquito causes filariasis?
Answer: Culex mosquito.
In simple words: Filariasis is spread through the bite of infected Culex mosquitoes.

Exam Tip: Associate malaria with Anopheles, dengue with Aedes, and filariasis with Culex.

Question 9. By destroying breeding grounds of mosquito is breeding to?
Answer: By destroying breeding grounds, we can prevent mosquitoes from laying eggs and multiplying in standing water to collect anywhere.
In simple words: Eliminating stagnant water stops mosquitoes from completing their aquatic life cycle.

Exam Tip: Mention source reduction and removal of stagnant water as key vector control measures.

Question 10. What in the symptoms of malaria fever?
Answer: High fever after chilling and shivering.
In simple words: Malaria typically causes sudden shivering followed by high fever and sweating.

Question 1. Eggs of culex mosquito are laid in
(a) Single
(b) Cluster in water
(c) Cluster in water
(d) Single in water
Answer: (b) Cluster in water
Culex eggs are laid in clusters forming a raft on the water surface.
In simple words: Culex mosquitoes lay multiple eggs joined together in water clusters.

Exam Tip: Look for the term cluster or raft when identifying Culex eggs.

Question 2. Larva of culex is at an angle to water surface, it is
(a) \(100^{\circ}\)
(b) \(45^{\circ}\)
(c) \(90^{\circ}\)
(d) \(360^{\circ}\)
Answer: (b) \(45^{\circ}\)
Culex larvae hang at an angle of \(45^{\circ}\) relative to the water surface.
In simple words: The larva maintains a slanted \(45^{\circ}\) angle while breathing at the water surface.

Exam Tip: Remember \(45^{\circ}\) for Culex and parallel/horizontal for Anopheles.

Question 3. Larva of anopheles is
(a) Parallel to water surface
(b) At right angle
(c) Vertical
(d) Angular
Answer: (a) Parallel to water surface
Anopheles larvae lie horizontally parallel to the water surface.
In simple words: Anopheles larvae float flat and parallel against the water surface.

Exam Tip: Parallel positioning ensures direct contact with air through spiracular plates.

Question 4. Which mosquito causes malaria?
(a) Anopheles
(b) Female anopheles
(c) Culex
(d) Aedes
Answer: (b) Female anopheles
Only female Anopheles mosquitoes transmit the malaria parasite.
In simple words: Female Anopheles mosquitoes are the specific vectors responsible for malaria.

Exam Tip: Always include "Female" before Anopheles for complete biological accuracy.