Q1. Describe the importance of classification.
Ans. Classification is important because of the following reasons :–
1. By classification we recognises the basic taxonomic units or species.
2. It tells us about the resemblances and relationships between various organisms.
3. It helps in understanding the evolution of organisms, as it gives us most of the information permitting a reconstruction of phylogeny of life.
4. It has great role in many fields like agriculture, public health and environmental biology. Exact identification of harmful pests, disease vectors a made possible which makes the control of disease much easier.
5. Several ornamental plants have been introduced by ...view middle of the document...
Their cell-wall is made of a tough complex sugar called chitin. Reproduction by budding or production of spores by asexual or sexual methods.
Some Examples of fungi are : Aspergillus, yeast and Rhizopus Penicillium.
Some fungi live in permanent, mutually dependent relationships with blue-green algae. The process is called symbiosis and such relationships are called symbiotic. These symbiotic life forms are called Lichens. In lichens, the plant body is made up of two individuals, an alga and a fungus. The alga produces sugar or alcohols by photosynthesis. The fungus can use these as a food source. The fungus surrounds and protects the alga and thus both are benefited by this symbiotic association. Lichens are slow growing and highly resistant to drying out.
Q4. What are bryophytes ? What are their features ? Make outline sketches of any two bryophytes.
Ans. It includes higher cryptograms. They grow on damp walls and on
the bark of tree. The plant body may be thalloid or leafy. True roots are absent. Instead, rhizoids develop. It includes two groups.
(a) Liverworts (b) Mosses.
Examples. Funaria, Marchantia, Riccia, Sphagnum etc.
Q5. Giving the characteristic features of phylum arthropoda, make labelled diagrams of any two arthrapods.
Ans. Anthropods constitute the largest group of animals. They are the animals with jointed feet/appendages.
1. These animals are bilaterally symmetrical and segmented.
2. Body covered with chitinous exoskeleton.
3. One or two pairs of jointed antennae are present.
4. The coelomic cavity is cantennae are present blood-filled are called haemocoel.
5. Body bears jointed appendages, and is divided into head, thorax and abdomen.
6. Circulatory system is open, i.e. blood doesn’t flow in blood vessels.
Examples : Palaemon, cockroach and butterfly.
Q7. Give the salient features of pisces. Make labelled diagrams of three bony fish and three cartilagnous fish.
Ans. Pisces are fish. Their main features are :–
1. They are exclusively water living animals.
2. Their skin is covered with scales/plates.
3. They obtain oxygen dissolved in water by using gills.
4. The body is streamlined, and a muscular tail is used for movement.
5. They are cold-blooded and their hearts have only two chambers.
6. They lay eggs.
7. Some fish varieties have their skeletons made of both bone and cartilage, such as Anabas, Sea horse, Rohu, and some have their skeletons made entirely of bone, e.g., Torpedo fish and sting ray (Trygon).
Q8. Distinguish between the five classes of vertebrates on the basis of characters like habitat, kind of exoskeleton, respiratory organs and other distinct features.
Ans. Differences between Pisces, Amphibia, Ropplia ares and mammals.
Character | Pisces | Amphibia | Reptilia | Aves | Mammals |
1. Habitat2. Exosk-
5. Heart6. Loco-
7. Others | AquaticSlimy scalesGillsCold-
blooded2 chamberedFinsBody is...