Class 9 NCERT Solutions Biology Chapter 7 - Diversity In Living Organisms
Relearn the variations that can be seen in life forms with TopperLearning’s NCERT Solutions for CBSE Class 9 Biology Chapter 7 Diversity in Living Organisms. Read these solutions before your exam for last-minute revision of concepts such as autotrophs, pteridophytes, phanerogams etc.
The online NCERT textbook solutions for CBSE Class 9 Biology also help you brush up the differences between angiosperms and gymnosperms, coelenterates and poriferans, and so forth. Also, revise lessons on arthropods, annelids and other chapter topics with our expert solutions for textbook questions and sample question papers.
Diversity In Living Organisms Exercise 80
Solution 1
There are large number of organisms and it is very difficult to study them individually, so classification enables us to deal with enormous diversity of life in an arranged manner.
Solution 2
i. Size: Organisms vary greatly in size-from microscopic bacteria to elephants, whales and large trees.
Diversity In Living Organisms Exercise 82
Solution 1
Solution 2
Solution 3
- Plants are autotrophs i.e. they are able to make their own food.
- Animals are hetrotrophs i.e. they cannot make their own food. They depend on plants directly or indirectly for their food.
Concept insight: Recall the difference between plant and animal cell.
Diversity In Living Organisms Exercise 83
Solution 1
Solution 2
Diversity In Living Organisms Exercise 85
Solution 1
Concept insight: Recall the basic structure of organisms of kingdom Monera and Protista.
Solution 2
Concept insight: Recall the basic characteristics of kingdom Protista.
Solution 3
Concept insight: Recall the hierarchy of classification.
Diversity In Living Organisms Exercise 88
Solution 1
Solution 2
Pteridophytes | Phanerogams |
(i) They have naked embryos. (ii)Reproductive organs are hidden or inconspicuous. (iii) Pteridophytes have special tissue for conduction of water but it is not much developed. |
(i) Embryo is present in seed. Seed also contains stored food. (ii) Reproductive organs are well developed (in gymnosperms cone and in angiosperms flower bear male and female organs). (iii)Phanerogams have well developed vascular tissue. |
Concept insight:
- Differences should always be written in tabular form.
- Differences should be written in terms of their significance.
- Write only those many numbers of differences as asked in the question.
- Give example wherever possible.
Solution 3
Gymnosperms | Angiosperms |
1. The plants bear naked seeds. 2. They produce cones formed of sporophytes. The sporophytes carry the male and female sex organs. 3. Ovules are not enclosed in ovary. 4. Plants of this group are usually evergreen, perennial and woody. |
1. Seeds are enclosed in fruits. 2. Reproductive organs are flowers. 3. Ovules are enclosed in ovary. 4. Plants of this group may be annual, biennial or perennial. They may be woody or non-woody. |
Concept insight:
- Differences should always be written in tabular form.
- Differences should be written in terms of their significance.
- Write only those many numbers of differences as asked in the question.
- Give example wherever possible.
Diversity In Living Organisms Exercise 94
Solution 1
Poriferan Animals | Coelenterate Animals |
1. These organisms have minute pores called ostia all over the body and a large opening called osculum at the top for the exit of water. 2. Body is made up of a single layer of cells. 3. Canal system for circulating water through the body present. 4. External skeleton present. The body design involves very little differentiation and division into tissues. 5. These are non-motile animals and are attached to some solid support. 6. Tentacles are absent. |
1. These organisms have a single pore. 2. Body is made of two layers of cells, one making the outer lining and the other the inner lining of the body. 3. No water canal system present in the body. 4. Skeleton absent. More body design differentiation is shown by these animals. 5. They are motile animals. Some species of this group live in colonies while others have a solitary life-span. 6. Tentacles are present. |
Concept insight:
- Differences should always be written in tabular form.
- Differences should be written in terms of their significance.
- Write only those many numbers of differences as stated in the question.
- Give example wherever possible.
Solution 2
Annelids | Arthropods |
1. They have true body cavity called 'coelom'. 2. Body bears lateral appendages for locomotion in the form of setae and Parapodia. 3. Organ differentiation occurs in a segmental fashion, with the segments lined up one after the other from head to tail. 4. They breathe through body surface. 5. They do not possess chitinous exoskeleton. 6.They have closed type of circulatory system. |
1. The body cavity is blood filled and called "haemocoel". 2. Jointed legs are there for locomotion. 3. These animals are also segmented but lack complete metamaric segmentation. 4. They posses different organs for breathing, like gills, trachea booklungs, etc. 5. Chitinous exoskeleton present. 6. Open type of circulatory system present. |
Concept insight:
- Differences should always be written in tabular form.
- Differences should be written in terms of their significance.
- Write only those many numbers of differences as stated in the question.
- Give example wherever possible.
Solution 3
Amphibians | Reptiles |
1. They can live both on land and in water. 2. They breathe either through gills or lungs. 3. Body is not covered with scales. 4. Their eggs don't have any tough and hard covering around them. 5. They lay eggs in water and fertilization takes place in water. |
1. They live either on land or in water. 2. They breathe through lungs only. 3. They have scales on their body. 4. The eggs have a hard covering. 5. Water is not necessary for fertilization. |
Concept insight:
- Differences should always be written in tabular form.
- Differences should be written in terms of their significance.
- Write only those many numbers of differences as stated in the question.
- Give example wherever possible.
Solution 4
Aves | Mammalia |
1. The body is covered with feathers. 2. Forelimbs are modified into wings. 3. They lay eggs. 4. No mammary glands to feed their young ones. 5. Bones have air cavities. |
1. The body is covered with hairs. 2. They don't have wings. 3. Most of them give birth to young ones. 4. They have mammary glands for the production of milk for the nourishment of the young ones. 5. Bones are solid, hard and filled with bone marrow. |
Concept insight:
- Differences should always be written in tabular form.
- Differences should be written in terms of their significance.
- Write only those many numbers of differences as stated in the question.
- Give example wherever possible.
Diversity In Living Organisms Exercise 97 (Ex.)
Solution 1
ii. It makes the study of different kinds of organisms much easier.
iii. It tells us about the inter-relationship among the various organisms.
iv. It helps us understanding the evolution of organisms.
v. It helps in the development of other life sciences easy.
vi. It helps environmentalists to develop new methods of conservation of plants and animals.
Solution 2
In case of classification of animals, the characteristics used to classify in a hierarchy are:
Solution 3
i. Complexity of cell structure - There are two broad categories of cell structure: Prokaryotic and Eukaryotic. Thus, two broad groups can be formed, one having prokaryotic cell structure and the other having eukaryotic cell structure. Presence or absence of cell wall is another important characteristic.
ii. Unicellular and multicellular organisms - This characteristic makes a very basic distinction in the body designs of organisms and helps in their broad categorizations.
iii. Mode of nutrition -Organisms basically have two types of nutritions - autotrophic (they can manufacture their own food) and heterotrophic (they obtain their food from external environment, i.e., from other organisms). Thus, organisms can be broadly classified into different groups on the basis of their mode of nutrition.
iv. Phylogenetic relationship - Phylogeny is the evolutionary history or ancestry of an organism. It is believed that the simple organisms are primitive and complex organisms are advanced. Thus, primitive and advance nature of organisms also helps in their classification into broad groups. For example, the Monera are believed to have given rise to Protista, from which the remaining three kingdom of multicellular organisms have evolved.
Solution 4
i. Whether the plant body has well differentiated, distinct components.
ii. whether the differentiated plant body has special tissues for the transport of water and other substances.
iii. The ability to bear seeds.
iv. Whether the seeds are enclosed within fruits.
Solution 5
i. Differentiation of the plant body.
ii. Distinct vascular (conduction) tissues.
iii. Seed producing ability.
iv. Seeds are enclosed within fruits or not.
Solution 6
Class | Pisces | Amphibia | Reptilia | Aves | Mammalia |
Characteristics |
Exoskeleton of scales; endoskeleton of bone/cartilage; breathing through gills. |
Gills in larva; lungs in most adults; slimy skin. |
Exoskeleton of scales; lays eggs outside water. |
Exoskeleton of feathers, lay eggs outside water, flight possible. |
Exoskeleton of hair, external ears, mostly giving birth to live young ones. |
Concept insight: Students should remember the main characteristics of kingdom Vertebrata.