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CHAPTER 3
BIODIVERSITY
Review Questions
Encircle the correct answer:(1) Which of the following is the correct way of writing a scientific name of an organism?
(a) Houbara bustard ✓
(b) E.coli
(c) Alium Cepa
(d) canis lupis
(2) Select the mismatched
(a) Plantae → Pteridophyta
(b) Fungi → Mucor
(c) Protista → Paramecium
(d) Animalia → Amoeba ✓
(3) Identify the correct sequence of classifying an organism.
(a) Species → Genus → Kingdom → Phylum → Class → Order → Family
(b) Kingdom → Phylum → Class → Order → Family → Genus → Species ✓
(c) Kingdom → Phylum → Class → Family → Order → Genus → Species
(d) Species → Genus → Class → Phylum → Order → Kingdom → Family
(4) All are involve in classification except
(a) Analogous ✓
(b) Homologous
(c) Cytology
(d) Genetics
(5) In the taxonomic hierarchy choose the term which encompasses all other in the list
(I) Genus (II) Species (III) Order (IV) Class
(a) I and II
(b) II
(c) II and III
(d) IV ✓
(6) In four kingdom classification, kingdom Metaphyta includes all of the following except.
(a) Algae ✓
(b) Angiosperm
(c) Gymnosperm
(d) Bryophyta
(7) In five kingdom system virus placed in
(a) Monera
(b) Protista
(c) Plantae
(d) None of these ✓
(8)Biological name of cat
(a) Felis catus ✓
(b) Azadirachta indica
(c) Alium Cepa
(d) Canis lupis
(9) Members of which kingdom have cell wall and are all heterotrophic
(a) Monera
(b) Protista
(c) Plantae
(d) Fungi ✓
(10) Biodiversity is effected with
(I) Pollution (II) Deforestation (III) Over hunting
(a) I only
(b) II only
(c) I and II
(d) I, II and III ✓
Fill In The Blanks:
(1) Degree of variation within or among the species exists on different regions of the earth called biodiversity or biological diversity.(2) All Species are given scientific names.
(3) Homologous Structures have different functions (physiology) but having similar internal architecture.
(4) Science of classification is called Taxonomy.
(5) Most protists are aquatic.
(6) Fungi are achlorophyllous and absorptive living organism.
(7) Virus is non-cellular obligate parasite.
(8) Scientific name of any organism should be italicized when printed.
(9) Cutting down of trees called Deforestation.
(10) Animals which are at the risk of extinction in future called endangered.
3. Define the following terms:
(i) Analogous (ii) Classification (iii) Species (iv) Family (v) Metazoa (vi) Mycelium (vii) Hyphae (viii) Genus (ix) Endangered species (x) Kingdom
Ans: (I) ANALOGOUS:
In biology, Analogous means different in structure and have same functions. Analogous structures (organs) are similar structures that evolved independently in two living organisms to serve the same purpose.
e.g. Wings of Butterfly and Bat.
(II) CLASSIFICATION:
Biologists mapped the whole diversity of organisms exist on earth, into simple groups. To understand about the characteristics of specific organisms individually, is simply called classification.
OR
OR
Classification is actually based on the similar and dissimilar characteristics what organisms shared with each other and by this biologists can easily study and identify the organisms.
OR
OR
To study such a diverse pack of organisms exist on earth, biologists classified the organisms into groups and sub groups. This grouping of organisms is called biological classification.
(III) SPECIES:
The smallest and basic unit of classification is species. Taxonomic studies consider a group of individual organisms with the fundamental similarities as a species. Thus all the members of the particular species share the similar characteristics and can naturally interbreed to produce a fertile offspring. Each species possesses its own distinct structural, ecological and behavioral characteristics.
(IV) FAMILY:
Family is a taxonomic rank in the classification of an organism between genus and order. Similar genera are grouped together into families, and similar families are group together into order.
e.g Human being belongs to family Hominidae.
(V) METAZOA:
- Animals (also called Metazoa) are eukaryotic organisms that form the biological kingdom Animalia.
- They are multicellular animals with differentiated tissues.
- They are ingestive heterotrophs without cell wall.
- They include all vertebrates and invertebrates except protozoa and sponge.
(VI) MYCELIUM:
Mycelium is a vegetative part of Fungi. It is made up of a thread like structure called hyphae.
Example: Mucor
(VII) HYPHAE:
A hypha is a long, branching filamentous structure, that make up the mycelium of a fungus. It helps in transportation of different material.
Example: Mucor
(VIII) GENUS:
Genus (Plural-Genera) is a taxonomic rank in the classification of an organism between family and specie. Similar genera are grouped together into families, and similar species are group together into genus.
e.g Human being belongs to genus Homo
(IX) ENDANGERED SPECIES:
Any species is at risk of extinction in future because of a sudden rapid decrease in its population or a loss of its critical habitat. Or Any species of plant or animal that was threatened with extinction could be called an endangered species.
Due to human activities such as entertainment or food, animals or plants are becoming endangered.
Example: Some of the endangered species of Pakistan are:
- Long Billed Vulture
- Green Sea Turtle
- Snow leopard
- Marco polo sheep
- European Otter
- Baluchistan Forest Dormouse
- Indus river dolphin
- Asian black bear
- Sindh Ibex (Markhor)
(X) KINGDOM:
The kingdom is the highest taxon of classification. Phyla or division are grouped together into kingdoms. All organisms are classified into five kingdoms. On the basis of similarities, each kingdom is further divided into smaller taxa (Phyla to Species).
e.g: Human being belongs to Kingdom Animalia.
4. Distinguish between the following in tabulated form:
(i) Plant kingdom and Animal kingdom
(ii) Monera and Protista
(iii) Fungi and Plantae
Ans: (i) Difference Between Plant Kingdom and Animal Kingdom
| S.NO. | Plant Kingdom | Animal Kingdom |
|---|---|---|
| 1. | It has multicellular eukaryote plants. | It has multicellular eukaryote animals. |
| 2. | Cell wall (made up of cellulose) is present, surrounds the cell membrane | Cell wall is absent in animal cells. |
| 3. | Chlorophyll is present in plant cells. | Chlorophyll is absent in animal cells. |
| 4. | Plants are autotrophic and they can prepare their own food. | Animals are heterotrophic and they cannot prepare their own food. |
| 5. | Organs of locomotion are absent, so they cannot move from one place to another. | Organs of locomotion are present, so they can move from one place to another. |
| 6. | Conductile and contractile system is absent | Conductile and contractile system is present. |
| 7. | Response to external stimuli is slow. | Response to external stimuli is fast. |
| 8. | e.g.: Bacteria, Algae, Fungi and all plants (Bryophytes, Pteridophytes, Gymno-Sperms, and angiosperms). | e.g.: All animals (Invertebrates-including protozoa, Vertebrate) |
(ii) Difference Between Monera and Protista
| S.NO. | Monera | Protista |
|---|---|---|
| 1. | They are unicellular Prokaryotic organisms. (Lower protists) | They are unicellular Eukaryotic organisms. (Higher protists) |
| 2. | They have cell wall but lack well developed Nucleus. | They have both well developed cell wall and Nucleus |
| 3. | Membrane bounded organelles are absent in the cell. | Membrane bounded organelles are present in the cell. |
| 4. | They are found in every habitat i.e. cosmopolitan. | They are primarily aquatic. |
| 5. | Monera are simple in structure with no complexity. | Prostita are complex in structure. |
| 6. | Mitochondria and chloroplast are absent. | Mitochondria present for cellular respiration and chloroplast present for photosynthesis process. |
| 7. | Example: Bacteria and cyanobacteria. | Example: Protozoa (Amoeba, Paramecium etc.) and unicellular algae. |
(iii) Difference Between Fungi and Plantae
| S.NO. | Fungi | Plantae |
|---|---|---|
| 1. | Fungi are eukaryotic heterotrophs (without Cholorophyll) living either as saprophyte, feeding on dead and decaying matter or as parasite. | Plants are eukaryotic autotrphs (with Cholorophyll) therefore they can produce their own food. |
| 2. | In fungi, cell wall is made up of chitin | In plants, cell wall is made up of cellulose |
| 3. | They reproduce by spores | They reproduce by seeds |
| 4. | They do not have roots, instead they have mycelium which are made up of filament like structure called hyphae | They have roots |
| 5. | Fungi are the decomposer of ecosystem. | Plants are the producer in ecosystem. |
| 6. | They are uninecleate or multinucliate per cell | They generally have single nucleus per cell. |
| 7. | Example: Microfungi, Macrofungi, slime and water mould | Macroalgae, Bryophytes, Pteridophytes, Gymnosperms, Angiosperms |
5. Write short answers of following questions:
(i) Why scientific naming is necessary? OR What is advantage of scientific naming? Or What are significance or importance of scientific names?
Ans: The Advantages or Significance or Importance Of Scientific Over Common Names
The scientific name is necessary because:
- They are accepted by speakers of all languages
- Each name applies only to one species, and
- Each species has only one name.
- Every species can be easily identified with just two words: Genra species
For example; common name of onion in Urdu is 'Piyaz' but in other regions it is also known as 'ganda' or 'basal' etc but in scientific language it is known as Allium cepa.
To avoid all these confusions that often arises from the use of a common name to designate different things in different places or from the existence of several common names for a single species, organisms are given scientific names by using binomial nomenclature. The value of this system is due to its widespread use and same name can be used all over the world, in all languages.
(ii) How living organisms are classified into two kingdom classification?
Ans: Two Kingdom classification:
Previously, the organisms were classified into two groups (Kingdom). These two kingdom classification system was given by Carlous Linnaeus. He is considered as the father of Taxonomy.
These two kingdoms were:
- Kingdom Plantae
- Kingdom Animalia
Basis Of Two Kingdom Classification
Plant Kingdom
- All the organisms possess cell wall were placed in plant kingdom.
- Organs of locomotion are absents. (They cannot move from one place to another by their own.)
- Chlorophyll is present.
- Plants are autotrophic in nature. (They can prepare their own food.)
- Conductile and contractile system is absent.
- Response to external stimuli is slow.
- e.g.: Bacteria, Algae, Fungi, Bryophytes, Pteridophytes, Gymno-Sperms, and angiosperms.
Animal Kingdom:
- All the organisms do not possess cell wall were placed in animal kingdom.
- Locomotory organs are present. (They can move from one place to another.)
- Chlorophyll is absent.
- They are heterotrophic in nature. (They can not prepare their own food and depends on other plants and animals for their food.)
- Conductile and contractile system is present.
- Response to external stimuli is fast.
- e.g.: Invertebrates (including protozoa), Vertebrate
KINGDOM CLASSIFICATION IN TABULAR FORM
(iii) Why virus is not placed in any kingdom?
Ans: Viruses are at the borderline of living and nonliving. Due to their crystalline nature, they are considered as non-living. They are acellular i.e. they do not have cellular organization yet show some characters of living organisms, as:
- Virus is non cellular obligate endoparasite (lives inside host cell).
- It does not have cellular organization but do have nuclear material either DNA or RNA.
- It has protein coat called capsid that encloses the nucleic acid.
- It reproduces only inside the host cell.
- It causes number of diseases in plant like tobacco Mosaic Disease etc and animals like, cold, flue, dengue, polio, hepatitis, AIDS etc.
(iv) Draw chart showing three kingdom classification.
Ans: Three Kingdom Classification:
(v) Why amoeba is not placed in animal kingdom?
Ans: Like animals, Amoeba is eukaryotic, it has ability to moves and it searches for its own food, but Amoeba is a unicellular organism. That is why amoeba or any other unicellular organism is not placed in animal kingdom. They all come under kingdom protista.
Ans: Cyanobacteria and bacteria were included in Kingdom Monera because they are neither plants nor animals, They are single celled organism and are prokaryotes. they are simplest organism . So, they were placed in Kingdom Monera.
6. Write detailed answers of the following questions:
(i) Describe in detail five kingdom classification.
Ans: Five Kingdom Classification:
Robert Whittaker in 1969 classified the organisms into Five kingdoms which clearly categorized fungi into a separate kingdom.
- Kingdom Monera
- Kingdom Protista
- Kingdom Fungi
- Kingdom Plantae
- Kingdom Animalia
Basis Of Five Kingdom Classification
This system of classification was based on:
- Cellular structure and body organization; unicellular Prokaryote, Unicellular and multicellular eukaryotes.
- Mode of nutrition; autotrophs (plants), Ingestive heterotrophs (animals) and absorptive heterotrophs (fungi).
Linkage Chart To Show The Establishment Of Five Kingdom System
(ii) What is taxonomic hierarchy? Explain aims of classification.
Ans: Taxonomic Hierarchy:
The groups into which organisms are classified are known as taxonomic categories or taxa (singular taxon). The taxa are arranged in ascending order and form a ladder, called taxonomic hierarchy.
All organisms are classified into five kingdoms, so Kingdom is the highest taxon of classification. On the basis of similarities, each kingdom is further divided into smaller taxa in the following way:
- Species: The smallest and basic unit of classification is species. Taxonomic studies consider a group of individual organisms with the fundamental similarities as a species. Thus all the members of the particular species share the similar structure and characteristics and can naturally interbreed to produce a fertile offspring. Each species possesses its own distinct structural, ecological and behavioral characteristics.
- Genera: Closely related species are grouped together into genera (singular-genus).
- Families: Similar genera are grouped together into families.
- Orders: families are grouped together into orders.
- Classes: orders are grouped together into classes.
- Phyla or Division: classes are grouped together into phyla or division.
- Kingdom: The kingdom is the highest taxon of classification. phyla or division are grouped together into kingdoms. All organisms are classified into five kingdoms. On the basis of similarities, each kingdom is further divided into smaller taxa. (Phyla - Species)
Aim Of Classification:
The main aims of this branch are:
- To determine similarities and dissimilarities among organisms so that they can be studied easily.
- To find the evolutionary relationship among organisms.
(iii) Describe effect of deforestation on biodiversity.
Ans: Effects of Deforestation:
The cutting down of trees for the conversion of forest into non forest land is known as Deforestation. Forests cover 31% of the land area on our planet. They produce vital osygen and provide for people and wild life. Many of the world's most threatened and endangered animals live in forests, and billions of people rely on its benefits. Forests offer food, fresh air, clothing, medicine and shelter.
Deforestation result with the great loss in Biodiversity such as;
- Increase in the concentration of green house gases (carbon dioxide, Methane, water vapour, Nitrous oxide etc.) which leads to Global warming.
- Temperature will be high that causes glaciers melting which is the reason of raising sea level and causes flood.
- It is also the reason of habitat loss of wild life.
- Soil erosion, low rainfall due to no transpiration is also the result of Deforestation.
MORE SHORT QUESTIONS
Q.1: Define extinct?
Ans: Extinct:
Some species have gone extinct means surety of not finding the last individual of that species in ecosystem. It is generally considered to be the death of the last individual of that species
Example: Dinosaurs
Q.2: Write down characteristics of kingdom Monera?
Ans: Kingdom Monera:
- It includes all the prokaryotes i.e. they are made of prokaryotic cells.
- Monerans are unicellular, although some types form chains, clusters, or colonies of cells.
- Cell wall is present which is made up of (Polysaccharide + amino acid) or cellulose.
- Nuclear membrane is absent.
- Cell organelles are absent.
- They are Motile or non motile. Most are heterotrophic (saprophyte/ parasite) but some are autotrophic (chemosynthetic photosynthetic) i.e they perform photosynthesis because they have chlorophyll in their cytoplasm.
- Example: Bacteria and cyanobacteria.
Q.3: Write down characteristics of kingdom Protista?
Ans: Kingdom Protista:
- It is the place for all the eukaryotic unicellular organisms, except yeast which some of them have the features of both plant and animal like.
- Cell wall is Present in some Protists.
- Nuclear membrane is present. Cell has membrane-bound cell organelles. Most protists are aquatic.
- All protists are motile. they can move in water through cilia, flagella, or pseudopodia.
- Example: It includes protozoa (Amoeba and Paramecium) and unicellular algae.
Q.4: Write down characteristics of kingdom Fungi?
Ans: Kingdom Fungi:
- It includes all the multicellular eukaryotic fungi.
- They are Achlorophyllous, absorptive heterotrophs.
- They have cell wall made up of mainly chitin.
- Nuclear membrane is present.
- They have loose tissue.
- They are non-motile.
- They have a body called Mycelium which is made up of a thread like structure called hyphae.
- Example: Mushroom, Mucor etc.
Q.5: Write down characteristics of kingdom Plantae?
Ans: Kingdom plantae:
- It includes all the multicellular, eukaryotic, photosynthetic organisms.
- Plants are autotrophic in nutritional mode, making their own food by photosynthesis.
- They have true cell wall mainly made up of cellulose.
- Nuclear membrane is present.
- They have tissues or organs.
- Most plants don't move but they grow and move towards light.
- Example: It includes multicellular Algae, bryophytes, pteridophytes, gymnosperm and angiosperms.
Q.6: Write down characteristics of kingdom Anmalia?
Ans: Kingdom Animalia:
- All animals are multicellular, eukaryotic.
- They are ingestive heterotrophs (depends on other organisms for their food).
- They lack cell wall and show movements.
- Nuclear membrane is present. They have well developed tissues, organs and organ systems. They have well developed locomotory organs and move from one place to another. It includes all vertebrates and invertebrates except protozoa.
- Example: Star fish, Kangaroo etc.
