WBBSE Class 7 Science Solutions Chapter 6 Morphological Diversity and Functions of Living Components of Environment

Detailed explanations in West Bengal Board Class 7 Science Book Solutions Chapter 6 Morphological Diversity and Functions of Living Components of Environment offer valuable context and analysis.

WBBSE Class 7 Science Chapter 6 Question Answer – Morphological Diversity and Functions of Living Components of Environment

(Page no. 182)

1. Write neatly in the table below, the names of plant food that you ate today and yesterday, Then mention in the table which food is obtained from which part of a plant.
Answer:

SI. No.	Names of the food	Which part of the plant
1.	Rice	Seed/fruit
2.	Roti	Seed/fruit
3.	Dal	Seed
4.	Brinjal	Fruit
5.	Spinach	Leaf

2. Give it a thought: are all foods that you get from under the soil really roots from plants? Write in the table below:
Answer:

SI. No.	Names of the food	Root/Stem
1.	Carrot	Root
2.	Beet	Root
3.	Potato	Modified stem
4.	Ginger	Modified stem
5.	Radish	Root

(Page no. 185)

1. Write down the nature of roots of the following plants and complete the chart :
Answer:

SI. No.	Plant Name	Root type
1.	Indian periwinkle	Tap root
2.	Four O’clock plant	Tap root
3.	Paddy	Fibrous root
4.	Mango	Taproot
5.	Cyanodon	Fibrous root
6.	Water hyacinth	Fibrous root

(Page no. 189)

1. Now try to tell that which plant parts of these following plants are used to climb up.

Plants	Organ
1. Gourd	(a) Root from nodes
2. Pea	(b) Tendrils from branches
3. Blu-pea flower	(c) Tendrils from leaf
	(d) Stem.

Answer:
1. b and c, 2 – d, 3 – a

Known objects	Stem	Not stem	Shape
Datashak	✓	X	thin, long
Cabbage	✓	X	round
Drumstick	X	✓	thin
Potato	✓	X	round
Colocasia	V	X	round or big and long

(Page no. 190)

SI. No.	Name	Type	Morphology	Function
1.	Spine of Bael	Modified aerial aerial stem stem modified into spine	long, sharp spine like	Self protection
2.	Offset of water hyacinth	Modified sub­aerial stem floating over water	soft and long like tube	to float on water
3.	Tuber of potato	Modified underground stem	round in shap	to store food
4.	Stem tendril of pumpkin	Modified aerial stem Creeper like	very thin and soft	to climb over support

(Page no. 192)

Specimen Leaf Name	Shape of that expanded portion of leaf
1. Jhanleaf	small and slender
2. Bamboo leaf	long and slender
3. Hibiscus leaf	Broad in the middle gradually becomes slender towards tip
4. Lotus leaf	Flat and round in shape
5. Chhatim leaf	Flat and short

(Page no. 194)

Leaf parts	Function
1. Lamina	(a) Produce food
2. Petiole	(b) Conduction of water and food
3. leaf base	(c) Holds lamina
	(d) Causes gaseous exchange
	(e) Keep branches attached to the stern

Answer:
1. a and d, 2. b and c, 3. e

(Page no. 195)

Leaf name	Work
1. Tendril of pea	(a) Helps in propagation
2. Spine of opentis	(b) Storage of food
3. Leaf of Aloevera	(c) Absorbs nitrogen from insects body
4. Leaf of Bryophyllum	(d) Helps to climb
5. Leaf of pitcher plant	(e) Prevents excess transpiration

Answer:
1 – d,  2 – e, 3 – b, 4 – a, 5 – c

(Page no. 195)

Plants with simple leaf	Plants with compound leaf
1. Mango	1. Tamarind
2. Banyan	2. Gulmohor
3. Jammun	3. Simul

Class 7 Science Chapter 6 Question Answer West Bengal Board – Morphological Diversity and Functions of Living Components of Environment

Fill in the blanks : (1 mark for each question)

1. ………………. protects the soft root tip from friction with soil particle when it enter the soil.
Answer:
Root cap.

2. Rice, Bryophyllum, grasses have ………………. root.
Answer:
adventitious.

3. An angle formed between leaf and stem, is called ……………….
Answer:
axil.

4. The potato which we eat is actually a ………………. where the plant stores its food for
future use.
Answer: modified shoot.

5. The part which attaches stem and leaf is called ……………….
Answer:
leaf base.

6. The flat expanded part of leaf is called ……………….
Answer:
lamina.

7. Animals differ in the sensitivity of their ………………. organs.
Answer:
olfactory.

8. ………………. mosquitoes spread malaria.
Answer:
Anopheles

9. Cell membranes are called ………………. membrane.
Answer:
selectively permeable

10. Concentrated salt solution is ………………. with respect to the RBC.
Answer:
hypertonic.

11. The stem of a sapling develops from the ………………. of an embryo.
Answer:
Plumule.

12. The roots of a sapling develops from the ………………. of an embryo.
Answer:
radicle

13. Mango is called ………………. fruit.
Answer:
simple

14. Custard apple is called ………………. fruit.
Answer:
aggregate

15. Jackfruit is a ………………. fruit.
Answer:
compound

B State whether True or False : (1 mark for each question)

1. Volatile compounds of human sweat can be recognized by Anopheles mosquito.
Answer:
true

2. Diffusion is faster at lower temperature.
Answer:
false

3. Excess use of insecticide reduces beneficial insects like honey bee.
Answer:
true

4. Seeds develop from the ovule after fertilization.
Answer:
true

5. A flower consists of three parts.
Answer:
false

6. Application of insecticide is a problem of pollination
Answer:
true

7. Deforestation of trees like shimul destroy the shelters of pollinating vectors like bats.
Answer:
true

8. Bats appear when fruits arc cut.
Answer:
false

9. Anopheles moscuitoes recognize the volatile compounds responsible for the sweet smell of fruits.
Answer:
false

10. The spreading of molecules is much faster in gas than in a solution.
Answer:
true

11. Tuberculosis bacteria can only reside in lungs of human.
Answer:
false

12. No bacteria can spoil honey easily.
Answer:
true

Match the column A with column B

Column A	Column B
a) In germination of pumpkin seeds b) In germination of mango seed c) Heat helps to keep our life d) Deforestation is a e) Excess use of insecticide f) Mango is a g) Jackfruit is the example of h) The part which attaches stem and leaf	i) compound fruit ii) is a problem of pollination iii) the cotyledons break the seed coat iv) is called a leaf base v) the cotyledons donot come out of the soil vi) simple fruit vii) problem of pollination viii) process going

Answer:
a) In germination of pumpkin seeds the cotyledons break the seed coat.
b) In germination of mango seed the cotyledons donot come out of the soil.
c) Heat helps to keep our life process going.
d) Deforestation is a problem of pollination.
e) Excess use of insecticide is a problem of pollination.
f) Mango is a simple fruit.
g) Jackfruit is the example of compound fruit.
h) The part which attaches stem and leaf is called a leaf base.

Very Short Questions and Answers : (1 mark for each question)

Question 1.
How does the water goes to leaves of a tree?
Answer:
By xylem tissue.

Question 2.
How does the prepared food goes to the lower most parts of plants?
Answer:
By phloem tissue.

Question 3.
Where does plants store the excess food?
Answer:
In fruits, sometimses in modified shoots.

Question 4.
Which part of plant holds branches, leaves, flowers and fruits?
Answer:
Stem.

Question 5.
How does a plant protect itself from herbivorous animals?
Answer:
By spine.

Question 6.
On bright sunlight, absorbed water from soil, evaporates through leaf. Which part of plant can prevent it?
Answer:
Stomata of plant.

Question 7.
How do Bamboo, Banana and palm propagate and keep their existance on Earth inspite of not producing flowers and seeds?
Answer:
By Vegetative Propagation.

Question 8.
Puinshak, laushak can produce food without leaves. Which other part can they use to do the same purpose?
Answer:
They use stem or other green parts of plant which has cholorophyll.

Question 9.
Find out the occasions at home when wood is required.
Answer:
As fuel, to make door, windows, furniture.

Question 10.
Do you know how paper is prepared?
Answer:
From bamboo, grass etc. paper is processed in factory.

Question 11.
Which transport vehicles need wood to construct?
Answer:
Hand cart, bullock cart, small vehicles.

Question 12.
How do plants help in your household cooking?
Answer:
By supplying fuel, vegetables, spices.

Question 13.
Which stem do you use as food?
Answer:
Patatc ginger etc.

Question 14.
Name the part of plant to make jute bag or your dress.
Answer:
Stem of jute, seed cover of cotton.

Question 15.
From which plant part we can use to make gum, mosquito repellent, tyre of cycle and varnish?
Answer:
Excrete of plant that secretes from stem.

Question 16.
Name some medicines which can be obtained from stem?
Answer:
quinine, resarpin, cincona.

Question 17.
Which provide shelter to birds, squirel, bat, monkeys at night?
Answer:
Trunks of big trees.

Question 18.
Name some insects which live on plant.
Answer:
Caterpillar, silkworm, cricket.

Question 19.
Why woods are attacked by insects?
Answer:
Insects get their necessary foods.

Question 20.
Who emits essential oxygen? Who absorbs your exhaled CO₂?
Answer:
Leaves of plant.

Question 21.
Why do you feel cold under a canopy in summer?
Answer:
Due to transpiration of plant.

Question 22.
Who absorbs polluted air of vehicles and cleans the nature?
Answer:
Green plant and trees.

Question 23.
How can be said the age of a plant from its stem?
Answer:
Number of rounds inside a stem is counted to know the age of plant.

Question 24.
Name some helpful insects which use leaves as food.
Answer:
Silkworm.

Question 25.
Name some harmful insects which use leaves as food.
Answer:
Pine Bark Beette, aphid, ants.

Question 26.
Which leaves are consumed by elephant, deer, cow and goat?’
Answer:
Grass, peepal leaf, Banyan leaf etc.

Question 27.
Which leaf ribs are used in our daily house hold clearing?
Answer:
Coconut, date palm.

Question 28.
Which leaf juice or extract is used as medicine?
Answer:
Tulshi, Basaka, Pudina, Kalmegh.

Question 29.
Which leaves of plants man uses for his livelihood?
Answer:
Tobacco leaf, Sal leaf. Tea leaf.

Question 30.
Which leaves are used for fuel?
Answer:
Dried sal leaf, mango leaf, jack fruit leaf.

Question 31.
Which leaves are used to make wall or shed?
Answer:
Coconut leaf, Hogla leaf

Question 32.
Name some leaves which are used for decoration?
Answer:
Mango leaf. Tamarisk leaf.

Question 33.
Which flower shows sepals or petals similar in shape and size?
Answer:
Hibiscus, Dhatura.

Question 34.
Parts of calyx corolla are not similar in which flower?
Answer:
ApArajita, Balsam.

Question 35.
Which flowers show all the four whorls?
Answer:
Hibiscus, Dhatura.

Question 36.
Which flower shows the absence of one or more whorls?
Answer:
Cucurbits.

Question 37.
Does the colour of petals can change (with change in attitude, season, day time)?
Answer:
Lotus and land-lily remains white after blooming in morning as the sunrise they become pink.

Question 38.
Why the petals of a flower are red in somewhere, yellow in somewhere, purple in somewhere or blue in some place else?
Answer:
Due to presence of different coloured pigments.

Question 39.
How does a plant benefit from the scent of petals?
Answer:
The scant attracts insects, birds and animals which help in pollination.

Question 40.
Name the plants which are nocturnal and which bloom in day.
Answer:
Sandhyamalati, Juhi and Jasmine are nocturnal; Rose, Merrigold, Sunflower bloom in day time.

Question 41.
Can you name some animals which can consume pollens?
Answer:
Ant, bee, birds.

Question 42.
What are the problems do encounter if we inhale pollen?
Answer:
Breathing problem, allergy.

Question 43.
How can man use flower colours?
Answer:
To make different coloured dye.

Question 44.
What is the relation of sunlight with blooming?
Ansswer:
The heat and light of sunlight helps in blooming.

Question 45.
Which part of flower forms fruit?
Answer:
Ovum.

Short Questions & Answers : (2 marks for each question)

Question 1.
What are the function of stem?
Answer:

• Keeps the plant firm
• Carrier of food
• Preparing food in green parts of stem
• Holds the branches
• Spreading branches
• Bear flower and bud
• Bear fruit
• Co-ordinates with all parts of plant.

Question 2.
Leaves are green but why are the petals coloured?
Answer:
Leaves had chlorophyll which are green in colour. It is needed to produce food. But petals are coloured to attract insects and birds which helps in pollination.

Question 3.
What is diffusion?
Answer:
The phenomenon, in which molecules of a substance spread through a gas or a solution from a region of higher concentration to a lower one is called diffusion.

Question 4.
From where does the seed develop? From which part of the flower?
Answer:
Seed develop from the ovule after fertilization. A seed is formed as a result of fertilization of an egg with a male gamete within the embryo sac of an ovule of Gynoecium of a flower.

Question 5.
Give example to prove that animals differ in the sensitivity of their olfactory organs.
Answer:
Small flies Drosophila appear when fruits are cut, as flies can recognize the volatile compounds responsible for the sweet smell of fruits. On the other hand, volatile compounds in human sweat can be recognized by Anopheles mosquitoes which spread malaria fly towards us for sucking blood.

Question 6.
What is osmosis?
Answer:
Osmosis is the diffusion of water molecules across a semi-permeable membrane from more dilute solution (with a lower solute concentration) to a less dilute solution (with a higher solute concentration).

Question 7.
What is Pheromone?
Answer:
Numerous volatile organic compounds play a vital role in reproduction of various animals including insects, tiger, elephant, deer etc. These compounds are called ‘pharomones’.

Long Questions & Answers : (3 marks for each question)

Question 1.
Write down the functions of different parts of seed.
Answer:

• Seed Coat : The outer covering of the seed is known as seed coat. Seed coat protects the inner part of a seed.
• Embryo: the embryo may be defined as the young or miniature plant, enclosed within the seed-coat. It develops from the fertilized egg.
• Cotyledons : The cotyledons, are also known as seed leaves, they store food material for the embryo.
• Radicle : The part of the axis which projects out of the cotyledons is called the radicle. Radicle gives rise to the primary root.
• Plumule : It develops from the embroyonic axis and gives rise to the primary root.

Question 2.
Describe the different parts of a root.
Answer:

• Root cap zone : The cap like part at the tip of root is root cap. It protects the soft root tip from friction with soil particle when it enter the soil. This region is called root cap zone.
• Growth zone : The part adjacent to root cap region does not have any hair. This part helps the root to increase in length and enters the soil. This is the growth zone of root.
• Root hair zone : The part just above growth zone has many hairy appendages, it is the root hair zone. Plant absorbs water and soluble minerals from soil with the help of these root hairs.
• Permanent zone : The hard part present above root hair region is the permanent zone. It firmly keeps the plant in position in soil.

Question 3.
Define – Node, Internode, Axil.
Answer:

• Node: The place of origin of branches on stem is called Node.
• Internode: The place between two nodes is called Internode.
• Axil: An angle is formed, between leaf and stem, it is called Axil.

Question 4.
What are the different types of leaves?
Answer:
There are two types of leaves —

• Simple leaf: The margin of the leaf whose blade/lamina is entire i.e. it is not lobbed, such types of leaf is called Simple leaf. Example — ‘Peepul’ plant have only one leaf blade.
• Compound leaf: In some plants the leaf is directed in many parts upto its midrib. This type of leaf is called Compound leaf. Example — The leaf of tamarind plant.

Question 5.
How many parts are there in a flower?
Answer:
A flower consists of four part. Each of these parts is called a whorl. They are —

• Calyx
• Corolla
• Androecium
• Gynoecium

Calyx: This is the outermost whorl and floral leaves of this whorl are called sepals. Sepals enclose the bud and protect the inner whorls. Calyx is inverted bell shaped and green in colour.

Corolla: It is the second whorl of floral leaves which are called petals. Petals fuse together and make different shapes in different flowers. Any flower colour is the colour of its petals. Their shape, size, smell and colours are different in different flowers.

Androecium: Androecium is the third whorl and male reproductive organ of a flower. It has a slender thread like part called stamen and a kidney-shaped sac are called Anther at tip. The yellow powdery mass in sac are called Pollen Graind.

Gynoecium: Gynoecium is the innermost whorl of the flower. It is the female reproductive organ of the flower. Ovary, style and stigma together form Carpel. All the Carpel of a flower together form Gynoecium.

Question 6.
How many types of seeds are there depending upon the number of cotyledons present in a seed?
Answer:
The seeds are of two types —
(a) Monocotyledonous seed — Which have a single cotyledon in their seeds. They give rise to monocotyledonous plants like wheat, rice, maize, onion and barley.

(b) Dicotyledonous seeds — Which have two cotyledons in their seeds. They give rise to dicotyledonous plants like mango, gram, pea, castor etc.

Question 7.
How many types of pollination are there?
Answer: There are two types of pollination —

• Self Pollination : When pollen is transferred to the stigma of same flower or different flower of the same plant them it is called Self Pollination.
• Cross Pollination : When pollen is transferred to the stigma of a flower of different plant of same type, then it is called Cross Pollination.

Question 8.
List some facts that hamper pollination.
Answer:

• Excess use of insecticide reduces beneficial insects like honey bee.
• Temperature differences caused change in bloom timing, thus hampering pollinations
• Deforestation of trees like simul destroy the shelters of pollinating vectors like bats. Titus pollination gets hampered.

Question 9.
List the properties of diffusion.
Answer:

• Diffusion is faster in the gas phase than in a solution.
• Diffusion of heavier molecules is slower than that of the lighter ones.
• Diffusion is faster at higher temperatures.

Question 10.
Why do snakes frequently protrude their tongues?
Answer:
Molecules of different volatile compounds from different animal bodies spread through air, and get stuck to the tongue of the snake. The snake than withdraws the tongue and touches the palate with it. A special organ called Jacobson Organ in the palate receives the molecules of odour. This elicits sensation in its brain. From this the snake gets to know about its surroundings.

Question 11.
What is Germination? Define the two types of Germination.
Answer:
The process of forming plantlet from seed is called Germination.

• In germination of pumpkin, tamarind seeds the cotyledons break the seed coat and come out at the soil. It is called Epigeal Germination.
• In Germination of pea, grams or mango seed the cotyledons do not come out of the soil It is called Hypogeal Germination.

Question 12.
What is ORS?
Answer:
In case of loose motion, huge quantity of water comes out through liquid stool and urine. At that time, take a big glass full of water. Add three teaspoons of sugar and a pinch of salt in it. Now drink three such glasses through out the day. It will compensate up the loss of water and salt in your body. It is called Oral Rehydration Solution or ORS.

Question 13.
When sunstroke occurs? What should we do then?
Answer:
If deficiency of salt and water occur for a longtime on a summer day man can become senseless at that time, it is called sunstroke. Then the patient should be lied down, clothes should be loosned. Then he/she should drink cold water and bodies should sponged in cold water also.

Question 14.
How do salt water and sweet water fishes maintain the water and salt level in their body?
Answer:
Sweet water fishes i.e. fishes of pond or river absorbs salt from water and excrete excess water out. On the other hand saline water fish excrete scanty water, they put excess salts out to maintain water and salt balance in their body.