Haryana State Board HBSE 9th Class Science Solutions Chapter 7 Diversity in Living Organisms Textbook Exercise Questions and Answers.
Haryana Board 9th Class Science Solutions Chapter 7 Diversity in Living Organisms
HBSE 9th Class Science Diversity in Living Organisms Intext Questions and Answers
Questions from Sub-section 7
Why do we classify organisms?
Various kind of animals and plants occur on earth/world. For example, on one hand in world, we have microscopic bacteria of a few micrometres in size, on the other hand we have long organisms like blue whale of approximate sizes of 30 metres. While redwood trees of size 100 metres are found in California. Their age and structures are different. Some organisms have simple structures while.some have complex. Therefore, to make easy the study of various forms of life, they are classified on the basis of similarities and dissimilarities.
Give three examples of the range of variations that you see in life forms around you.
(1) On one hand in the world, we have microorganisms like bacteria which can be viewed under a microscope, on the other hand we have 30 metres long blue whale.
(2) 100 metres long red wood trees are found in California whereas lichen, are visible merely like small spots.
(3) Tortoise remains alive for three hundreds years. While insects like mosquitoes have a life-span of a few days.
Questions from Sub-section 7.1
Which do you think is a more basic characteristic for classifying organisms ?
(i) the place where they live. (A) the kind of cells they are made. Why ?
(A) The kind of cells they are made. It is a basic characteristic of classification because organisms with, nucleated cells have their pathways organised in very different ways than the organisms without nucleated cells.
What is the primary characteristic on which the first division of organisms is made?
Greek thinker Aristotle classified organisms according to whether they lived on land, water and air.
On what bases are plants and animals put into different categories?
Plants and animals are classified on the basis of cell wall found in their cells. Plants contain cell wall while animals are not.
Questions from Sub-section 7.2
Which organisms are called primitive and how are they different from the so-called advanced organisms?
The earlier developed organisms on the earth are called primitive organisms. Another kind of organism means developed organisms from lower organisms are called advanced organisms.
Will advanced organisms be the same as complex organisms? Why?
Yes, advanced organisms are complex organisms because earlier organisms are developed by complexity. So simple organisms changed into advanced organisms.
Questions from Sub-section 7.3
What is the criterion for the classification of organisms as belonging to the kingdom Monera or Protista?
Cell structure, mode of nutrition and body organisation are the basis of the classification of Monera or Protista.
In which kingdom will you place an organism which is single-celled, eukaryotic and photosynthetic?
In the hierarchy of classification, which grouping will have the smallest number of organisms with a maximum of characteristics in common and which will have the largest number of organisms?
The group ‘species’ will have the smallest number of organisms with maximum common characteristics. The largest number of organisms is placed in the ‘kingdom.’
Questions from Sub-section 7.4
Which division among plants has the simplest organisms?
How are pteridophytes different from the phanerogams?
These are lower categories plants. Their body divided into roots, stem and leaves. They have well-developed vascular tissues, the xylem and phloem. The mature leaves bear spores inside sporangia. After fertilization, the embryo developed inside them, e.g. fern.
These are higher categories plants. Roots, stem, leaves, flower, fruit and seeds are found in them. They are produced sexually by means of seeds, e.g. wheat, maize, etc.
How do gymnosperms and angiosperms differ from each other?
There are the following differences between gymnosperms and angiosperms
1. They have naked seeds.
2. Seeds are not enclosed in the fruit.
3. They are mostly found in mountain plants.
4. Pine and Cycas are its examples.
1. They have not naked seeds.
2. Seeds are enclosed in the fruit.
3. These are almost found in all groups of land plants.
4. Pea and wheat are its examples.
Questions from Sub-section 7.5
How do poriferan animals differ from Coelenterate animals ?
There are following differences between Poriferan animals and Coelenterate animals :
1. They are the simplest multicellular animals.
2. They bear pores all over the body.
3. They are flat, round sac or branched in shape like vase.
4. They are sessile.
5. They possess skeleton made up of spongin.
For example: Sycon, Spongilla.
1. They are complex multicellular animals.
2. They do not bear pores on the body.
3. They bear tentacles in the body.
4. They are sessile but some are free swimming.
5. They possess outer skeleton made up of lime.
For example: Hydra, Physalia.
How do Annelid animals differ from Arthropods ?
There are following differences between Annelid and Arthropods animals :
1. It is the smallest phylum.
2. They are segmented externally.
3. They have closed circulatory system.
4. They have no compound eyes.
5. Their body is not divided into head, thorax and abdomen.
6. They are bisexual.
Examples: Earthworm, Leach and Nereis.
1. It is the largest phylum in the animal kingdom.
2. They are covered externally by jointed exoskeleton.
3. They have an open circulatory system.
4. They have compound eyes.
5. Their body is divided into three parts head, thorax and abdomen.
6. They are unisexual.
Examples: Butterfly, Spider, Housefly and Prawn etc.
What are the differences between Amphibians and Reptiles ?
There are following differences between Amphibians and Reptiles:
1. They live in or near freshwater and moist land.
2. Their body lacks scales.
3. Respiration occurs by gills, lungs or skin.
4. They can move their eyelids.
5. They are cold blooded vertebrates.
Examples: Frog, Bufo and Hyla etc.
1. They mostly live on land.
2. Their body have scales.
3. Respiration occurs by lungs only.
4. They cannot do so.
5. They are cold blooded terrestrial or aquatic.
Examples: Lizard, Chameleon and Snake etc.
What are the differences between animals belonging to the Aves group and those in the mammalia group ?
There are following differences between aves group and mammalia group:
1. Their body is covered by feathers.
2. They lay eggs.
3. Teeth are absent in their beak.
4. They have wave like body.
5. Their bones have air cavities.
6. Air sacs are present in their lungs.
Examples: Parrot, Pigeon and Crow.
1. Their body is covered by hair.
2. They give birth to their young ones.
3. Teeth are present in their mouth.
4. They have not.
5. They have solid bones.
6. Air sacs are not present in their lungs.
Examples: Human, Cow and Bat.
HBSE 9th Class Science Diversity in Living Organisms Textbook Questions and Answers
What are the advantages of classifying organisms ?
There are following advantages of classifying organisms:
(1) Classification makes the study of organisms easy.
(2) It helps to understand the origin of organisms and their interrelationship.
(3) It gives an idea of similarities and dissimilarities between organisms.
(4) It works as a base for other branches of biology.
(5) It projects before us a picture of all life forms clearly.
How would you choose between two characteristics to be used for developing hierarchy in classification?
There are two characteristics to be used for developing hierarchy in classification: cell structure and body organisation. They are developing a hierarchy in classification. Body organisation is the main character in which body parts do work.
Explain the basis for grouping organisms into five kingdoms.
There are the following main criteria on the basis of Whittaker’s five kingdoms :
1. Monera: Cell wall present in these unicellular prokaryotic organisms. They can be both autotrophic or heterotrophic. Examples: Bacteria, Blue-green algae, Mycoplasma.
2. Protista: These are unicellular eukaryotic, autotrophic, heterotrophic or both. Cilia or flagella are found in them for moving. Examples: Paramecium, Unicellular algae, Protozoans, Diatoms, etc.
3. Fungi: These are heterotrophic eukaryotic organisms. They use decaying organic material as food. So they called saprophytes. They have cell walls made of a tough complex sugar called chitin. Examples: Yeast, Mushrooms, Agaricus, etc.
4. Plantae: They are multicellular eukaryotes and autotrophs organisms having cell wall. They use chlorophyll for photosynthesis. Example: All green plants.
5. Animalia: They all are multicellular eukaryotic heterotrophic organisms. Cell wall is not present in them.
What are the major divisions in the Plantae? What is the basis for these divisions?
The major divisions in Plantae are :
The basis of these divisions are –
(i) Differentiation of plant body into distinct components
(ii) Special tissues for the transportation of water and other substances
(iii) Ability to bear seeds, naked or enclosed in fruits.
How are the criteria for deciding divisions in plants different from the criteria for deciding the subgroups among animals ?
Mostly the body of all the plants is developed according to their capacity to make food. Although, the growth of animals’ bodies depends on the food getting from other sources. It is the main basis of classification between animals and plants because plants are autotrophs and animals are heterotrophs.
Explain how animals in Vertebrata are classified into further subgroups.
All chordates possess the following features:
(ii) dorsal nerve cord
(iv) paired gill pouches
Vertebrates are grouped into five classes:
(i) They are water-living animals found in both saline and freshwater.
(ii) They lay eggs and poikilothermic animals.
(iii) Their skin is covered with scales.
(iv) Their body is streamlined.
(v) Respiration occurs by gills.
(vi) They have two-chambered hearts.
(vii) They have fins on their body.
Torpedo, Rohu, Shark, Tuna, Scoliodon, Sea horse, Electric ray.
(i) They live in freshwater and moist land.
(ii) Their body is without scales.
(iii) Most of them have two pairs of pentadactyl (five digits) limbs.
(iv) Respiration occurs by gills, lungs or skin.
(v) They have a three-chambered heart.
Frog, Toad, Hyla.
(i) They are mostly land vertebrates.
(ii) Their skin is covered by scales.
(iii) Respiration occurs by lungs only,
(iv) They have a three-chambered heart. Only crocodiles have a four-chambered heart.
(v) They are unisexual.
Hemidactylus (Lizard), Chameleon, Draco (Flying Lizard).
(i) They are found all over the world.
(ii) Forelimbs are modified into wings.
(iii) Body covered with feathers.
(iv) Endoskeleton is made up of light bones with air cavities.
(v) Teeth are not present in their beak.
(vi) Respiration is by lungs only. Lungs have air sacs.
(vii) Heart is completely four-chambered.
Examples: Pigeon, Peacock, Sparrow, Ostrich, etc.
(i) They are often found inland areas.
(ii) Their body is covered by hair.
(iii) Respiration in them occur by lungs only.
(iv) They have a completely four-chambered heart.
(v) They have mammary glands to nourish their young ones.
(vi) They are unisexual.
Examples: Kangaroo, Rat, Whale, Squirrel, Elephant, Rabbit, Bat, Chimpanzee, Man, etc.