Tiêu đề 7 Diversity living organisms.pdf ✅

Biology Diversity in living organisms Some Typical Questions Q1. Define phylogeny. Ans. the evolutionary history of a group of organisms is termed as phylogeny. Q2. Give one point of difference between notochord and never cord. Ans. Notochord is flexible rod of turgid cells along the back of chordate ventral to the never cord. It is replaced by a jointed vertebral column. Never cord is a collection of never fibers inside the vertebral column. Q3. Give one example of hemichordata, urochordata and cephalochordate. Ans. (i) Hemichordata – Balonoglossus (ii) Urochordata- - Herdmania (iii) Cephalochordata – Amphioxus. Q4. Why whales are not grouped in the fishes? Ans. Whales can swim in water like the fishes but are not fish as they respise with lungs and have four chambered heart and mammary glands. So they are mammals. Q5. Give one example of each: (i) Asymmetry, redial and bilateral symmetry (ii) Acoelomates, pseudocoelomate and advanced than the fishes? Ans. (i) Amoeba, Hydra and a fish. Q6. Why Euglena is called plant-animal? Ans. Euglena has certain plant characters like having chloroplasts and certain animal characters like having flagellum, eye-spot, etc.
Q7. Name the group of organisms which have dicondylic skull. Ans. Amphibia and mammals Q8. Give one point of difference between Gymnosperms and Angiosperms. Ans .Seeds are naked or exposed in gymnosperms but seeds are covered by fruit wall or pericarp in angiosperms. Q9. Identify the animal group having: (i) Body spiny and redial symmetry (ii) Bones light and below (iii) 4 pairs of jointed legs and no wings. (iv) Soft bodied animals supported by calcareous shells. (v) External ear or pinna. Ans. (i) Echinodermata (ii) Aves (iii) Arachnida (iv) Mollusca (v) Mammalia Q10. What is haemocoel? Which groups of animals have haemocoel? Ans. The blood filled cavity is known as haemocoel. Example- Arthropoda and Mollusca Q11. Differentiate the nature of skin in four classes of tetrapoda. Ans. The nature of skin in four classes of tetrapode are- (i) Class Amphibia- Thin, moist, glandular and respiratory skin. (ii) Class Reptilia- Dry and non-glandular skin with scales. (iii) Class Aves- Dry and non-glandular skin with feathers. (iv) Class Mammalia- Glandular skin with hairs. Q12. List a few flight adaptations in birds. Ans. (i) Forelimbes are modified into wings. (ii) Body is covered by pneumatic having air feathers. (iii) Long bones are pneumatic having air cavities.
(iv)Body is stream-lined to reduce air resistance. (v) Well developed flight muscles. (vi)Presence of air sacs to help in double respiration (vii)Tail feathers from a steering apparatus (viii)They have acute vision. Q13. In what way, amphibians are advanced than the fishes? Ans. Amphilbians have three-chambered heart and lungs for respiration, while fishes have two-chambered heart and gills for respiration. Q14. Why are protozoa called early animals? Ans. protozoa are called early animals because pro means ancient and zoo means animals. They have continued to exist on earth since the origin of life and are unicellular. Q15. Name the organisms which has (i) Setae and Para podia (ii) Tube feet Ans. (i) Nereis (ii) Starfish Text Book Question: Q1. Give three example of the range of variations that you se in life forms around you. Ans. (i) Size: It varies from microscopic organisms (e.g., bacteria, size 0.5-5.0 um) to very large sized animals (e.g., Blue whale, 30meters long) and trees (e.g., Redwood tree, height 100 meters).
(ii)Life span: May fly lives for one day, most mosquitoes for a few days while some Pine trees live for thousands of years. (iii)Color: Jelly fish and many worms are colorless. Birds, butterflies and flowers are variously colored brightly. Q2. What is the primary characteristic on which the first division of organisms is made? Ans. type of cell, prokaryotic (genetic material or nucleoid free in cytoplasm) and eukaryotic (genetic material enclosed in nucleus). Q3. Which organisms are called primitive and how are they different from the so called advanced organisms? Ans. primitive organisms are those organisms which have simple ancient body design. There has been little change over a long period of time. Specializations are fewer. Advanced organisms are more recent organisms. They are also called higher organisms because they possess several specializations. They are hence, more complex. Q4. What is the criterion for classification of organisms as belonging to kingdom Monera or Protista? Ans. Cell structure is used as a criterion for placing an organism in monera or prostista. In monera the cell are prokaryotic. Membrane bound cell organelles are absent. In protista the cells are eukaryotic. Membrane bound cell organelles are present. Protiste contains only unicellular eukaryotes. Monera may have unicellular or multi cellular forms. Q5. 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. Ans. (i) small number (one) with maximum common characteristics – Species