done 12th Biology Organisms and population

• question_answer1)
  How is diapause different from hibernation? 
  View Answer play_arrow

• question_answer2)
  If a marine fish is placed in a fresh-water aquarium, will the fish be able to survive? Why or why not? 
  View Answer play_arrow

• question_answer3)
  Define phenotypic adaptation. Give one example. 
  View Answer play_arrow

• question_answer4)
  Most living organisms cannot survive at temperature above 45°C. How are some microbes able to live in habitats with temperatures exceeding 100°C? 
  View Answer play_arrow

• question_answer5)
  List the attributes that populations but not the individuals possess. 
  View Answer play_arrow

• question_answer6)
  If a population growing exponentially doubles in size in 3 years, what is intrinsic rate of increase (r) of the population? 
  View Answer play_arrow

• question_answer7)
  Name important defence mechanisms in plants against herbivory. 
  View Answer play_arrow

• question_answer8)
  An orchid plant is growing on the branch of mango tree. How do you describe this interaction between the orchid and the mango tree? 
  View Answer play_arrow

• question_answer9)
  What is the ecological principle behind the biological control method of managing with pest insects? 
  View Answer play_arrow

• question_answer10)
  Distinguish between: (a) Hibernation and aestivation; (b) Ectotherms and endotherms.  
  View Answer play_arrow

• question_answer11)
  Write a short note on: (a) Adaptations of desert plants and animals. (b) Adaptations of plants to water scarcity. (c) Behavioural adaptations in animals. (d) Importance of light to plants. (e) Effect of temperature or water scarcity and the adaptations of animals.  
  View Answer play_arrow

• question_answer12)
  List the various abiotic environmental factors. 
  View Answer play_arrow

• question_answer13)
  Give an example for: (a) An endothermic animal. (b) An ectothermic animal. (c) An organism of benthic zone.  
  View Answer play_arrow

• question_answer14)
  Define population and community. 
  View Answer play_arrow

• question_answer15)
  Define the following terms and give one example of each: (a) Commensalism (b) Parasitism (c) Camouflage (d) Mutualism (e) Interspecific competition.  
  View Answer play_arrow

• question_answer16)
  With the help of suitable diagram describe the logistic population growth curve. 
  View Answer play_arrow

• question_answer17)
  Select the statement which best explains parasitism: (a) One organism is benefitted (b) Both the organisms are benefitted (c) One organism is benefitted, other is not affected (d) One organism is benefitted, other is affected  
  View Answer play_arrow

• question_answer18)
  List any three important characteristics of a population and explain. 
  View Answer play_arrow

• question_answer19)     Autecology is the (a) relation of a population to its environment   (b) relation of an individual to its environment (c) relation of a community to its environment   (d) relation of a biome to its environment

  View Answer play_arrow

• question_answer20)   Ecotone is (a) a polluted area (b) the bottom of a lake (c)a zone of transition between two communities (d) a zone of developing community

  View Answer play_arrow

• question_answer21)   Biosphere is (a) a component in the ecosystem (b) composed of the plants present in the soil (c) life in the outer space (d) composed of all living organisms present on earth which interact with the physical environment

  View Answer play_arrow

• question_answer22)   Ecological niche is (a) the surface area of the ocean (b) an ecologically adapted zone (c) the physical position and functional role of a species within the community (d) formed of all plants and animals living at the bottom of a lake

  View Answer play_arrow

• question_answer23)   According to Alien's rule, the mammals from colder climates have (a) shorter ears and longer limbs                              (b) longer ears and shorter limbs (c) longer ears and longer limbs                                 (d) shorter ears and shorter limbs

  View Answer play_arrow

• question_answer24)   Salt concentration (salinity) of the sea measured in parts per thousand is (a) 10-15                              (b) 30-70                              (c) 0-5                                   (d) 30-35

  View Answer play_arrow

• question_answer25)   Formation of tropical forests needs mean annual temperature and mean annual precipitation as (a)18-25°Cand 150-400 cm                            (b)5 - 15°C and 50 -100 cm (c)30-50°Cand 100-150 cm                            (d) 5-15°C and 100-200 cm

  View Answer play_arrow

• question_answer26)   Which of the following forest plants controls the light conditions at the ground? (a) Lianas and climbers  (b) Shrubs                           (c) Tall trees                       (d) Herbs

  View Answer play_arrow

• question_answer27)   What will happen to a well growing herbaceous plant in the forest if it is transplanted outside the forest in a park? (a) it will grow normally (b) It will grow well because it is planted in the same locality (c) It may not survive because of change in its micro climate (d) It grows very well because the plant gets more sunlight

  View Answer play_arrow

• question_answer28)   If a population of 50 Paramedum present in a pool increases to150 after an hour, what would be the growth rate of population? (a) 50 per hour                  (b) 200 per hour               (c) 5 per hour                     (d) 100 per hour

  View Answer play_arrow

• question_answer29)   What would be the per cent growth or birth rate per individual per hour for the same population mentioned in the previous question (a) 100                                  (b)200                                   (c)50                                      (d)150

  View Answer play_arrow

• question_answer30)   A population has more young individuals compared to the older individuals. What would be the status of the population after some years? (a) It will decline                                                               (b) It will stabilize             (c) It will increase                                                             (d) It will first decline and then stabilize

  View Answer play_arrow

• question_answer31)   What parameters are used for tiger census in our country's national park sand sanctuaries? (a) Pug marks only                                                           (b) Pug marks and faecal pellets (c) Faecal pellets only                                                     (d) Actual head counts

  View Answer play_arrow

• question_answer32)   Which of the following would necessarily decrease the density of a population in a given habitat? (a) Natality> mortality                                                    (b) Immigration > emigration (c) Mortality and emigration                                       (d) Natality and immigration

  View Answer play_arrow

• question_answer33)   A protozoan reproduces by binary fission. What will be the number of protozoans in its population after six generations? (a) 128                                  (b)24                                     (c) 64                                     (d)32

  View Answer play_arrow

• question_answer34)   In 2005, for each of the 14 million people present in a country, 0.028were born and 0.008 died during the year. Using exponential equation ,the number of people present in 2015 is predicted as (a) 25 millions                    (b) 1 7 millions                   (c) 20 millions                     (d) 18 millions

  View Answer play_arrow

• question_answer35)   Amensalism is an association between two species where (a) one species is harmed and other is benefitted (b) one species is harmed and other is unaffected (c) one species is benefitted and other is unaffected (d) both the species are harmed.

  View Answer play_arrow

• question_answer36)   Lichens are the associations of (a) bacteria and fungus                                                 (b) algae and bacterium (c) fungus and algae                                                       (d) fungus and virus

  View Answer play_arrow

• question_answer37)   Which of the following is a partial root parasite? (a) Sandal wood               (b) Mistletoe                     (c) Orobanche                   (d) Ganoderma

  View Answer play_arrow

• question_answer38)   Which one of the following organisms reproduces sexually only once in its life time? (a) Banana plant               (b) Mango                           (c) Tomato                          (d) Eucalyptus

  View Answer play_arrow

• question_answer39)     Species that can tolerate narrow range of temperature are called......

  View Answer play_arrow

• question_answer40)   What are eurythermic species?

  View Answer play_arrow

• question_answer41)   Species that can tolerate wide range of salinity are called........

  View Answer play_arrow

• question_answer42)   Define stenohaline species.

  View Answer play_arrow

• question_answer43)   What is the interaction between two species called?

  View Answer play_arrow

• question_answer44)     What is commensalism?

  View Answer play_arrow

• question_answer45)   Name the association in which one species produces poisonous substance or a change in environmental conditions that is harmful to another species.

  View Answer play_arrow

• question_answer46)   What is mycorrhiza?

  View Answer play_arrow

• question_answer47)   Emergent land plants that can tolerate the salinities of the sea are called.

  View Answer play_arrow

• question_answer48)   Why do high altitude areas have brighter sunlight and lower temperatures as compared to the plains?

  View Answer play_arrow

• question_answer49)   What is homeostasis?

  View Answer play_arrow

• question_answer50)   Define aestivation.

  View Answer play_arrow

• question_answer51)   What is diapause and its significance?

  View Answer play_arrow

• question_answer52)   What would be the growth rate pattern, when the resources are unlimited?

  View Answer play_arrow

• question_answer53)   What are the organisms that feed on plant sap and other plant parts called?

  View Answer play_arrow

• question_answer54)   What is high altitude sickness? Write its symptoms.

  View Answer play_arrow

• question_answer55)   Give a suitable example for commensalism.

  View Answer play_arrow

• question_answer56)   Define ectoparasite and endoparasite and give suitable examples.

  View Answer play_arrow

• question_answer57)   What is brood parasitism? Explain with the help of an example.

  View Answer play_arrow

• question_answer58)     Why are coral reefs not found in the regions from West Bengal to Andhra Pradesh but are found in Tamil Nadu and on the east coast of India?

  View Answer play_arrow

• question_answer59)   If a freshwater fish is placed in an aquarium containing sea water, will the fish be able to survive? Explain giving reasons.

  View Answer play_arrow

• question_answer60)   Why do all the freshwater organisms have contractile vacuoles whereas majority of marine organisms lack them?

  View Answer play_arrow

• question_answer61)   Define heliophytes and sciophytes. Name a plant from your locality that is either heliophyte or sciophyte.

  View Answer play_arrow

• question_answer62)   Why do submerged plants receive weaker illumination than exposed floating plants in a lake?

  View Answer play_arrow

• question_answer63)   In a sea shore, the benthic animals live in sandy, muddy and. Rocky substrata and accordingly developed the following adaptations. (a) Burrowing (b) Building cubes (c) Holdfasts/peduncle Find the suitable substratum against each adaptation.

  View Answer play_arrow

• question_answer64)   Categorise the following plants into hydrophytes, halophytes, mesophytes and xerophytes. Give reasons for your answers. (a) Salvima                          (b) Opuntia                         (c) Rhizophora                   (d) Mangifera

  View Answer play_arrow

• question_answer65)   In a pond, we see plants which are free-floating; rooted-submerged, rooted emergent rooted with floating leaves. Write the type of plants against each of them.  

  Plant Name	Type
  (a)Hydrilla (b)Typha (c)Nymphcieci (d)Lemna (e)VaUisneria

   

  View Answer play_arrow

• question_answer66)   The density of a population in a habitat per unit area is measured indifferent units. Write the unit of measurement against the following (a) Bacteria                         ........... (b) Banyan                          ........... (c) Deer                                                ........... (d) Fish                                 ...........

  View Answer play_arrow

• question_answer67)             (a) Label the three tiers 1, 2, 3 given in the above age pyramid. (b) What type of population growth is represented by the above age pyramid?

  View Answer play_arrow

• question_answer68)   In an association of two animal species, one is a termite which feeds on wood and the other is a protozoan Thchonympba present in the gut of the termite. What type of association they establish?

  View Answer play_arrow

• question_answer69)   Lianas are vascular plants rooted in the ground and maintain erectness of their stem by making use of other trees for support. They do not maintain direct relation with those trees. Discuss the type of association the lianas have with the trees.

  View Answer play_arrow

• question_answer70)   Give the scientific names of any two microorganisms inhabiting the human intestine.

  View Answer play_arrow

• question_answer71)   What is a tree line?

  View Answer play_arrow

• question_answer72)   Define 'zero population growth rate'. Draw a age pyramid for the same.  

  View Answer play_arrow

• question_answer73)   List any four characters that are employed in human population census.

  View Answer play_arrow

• question_answer74)   Give one example for each of the following types (a) Migratory animal              (b) Camouflaged animal (c) Predator animal               (d) Biological control agent (e) Phytophagous animal          (f) Chemical defense agent

  View Answer play_arrow

• question_answer75)   Fill in the blanks  

  Species A	Species B	Type of Interaction	Example
  + + +	- +	Commensalism

   

  View Answer play_arrow

• question_answer76)   Observe the set of 4 figures A, B, C and D and answer the following questions. I. Which one of the figures shows mutualism? II. What kind of association is shown in D? III. Name the organisms and the association in C. IV. What role is the insect performing in B?  

  View Answer play_arrow

• question_answer77)     Comment on the following figure: I, II and III, A, B, C, D, G, P, Q, R, S are species.    

  View Answer play_arrow

• question_answer78)   An individual and a population has certain characteristics. Name these attributes with definitions.  

  View Answer play_arrow

• question_answer79)     The following diagrams are the age pyramids of different populations. Comment on the status of these populations.    

  View Answer play_arrow

• question_answer80)   Comment on the growth curve given below.

  View Answer play_arrow

• question_answer81)   A population of Paramedumcaudatum was grown in a culture medium. After 5 days the culture medium became overcrowded with Paramedumand had depleted nutrients. What will happen to the population and whattype of growth curve will the population attain? Draw the growth curve.  

  View Answer play_arrow

• question_answer82)   Discuss the various types of positive interactions between species-

  View Answer play_arrow

• question_answer83)   In an aquarium two herbivorous species of fish are Living together and feeding on phyto planktons. As per the Cause's principle, one of the species is to be eliminated in due course of time, but both are surviving well in the aquarium. Give possible reasons.

  View Answer play_arrow

• question_answer84)   While living in and on the host species, the animal parasite has evolved certain adaptations. Describe these adaptations with examples.

  View Answer play_arrow

• question_answer85)   Do you agree that regional and local variations exist within each biome? Substantiate your answer with suitable example.

  View Answer play_arrow

• question_answer86)   Which element is responsible for causing soil salinity? At what concentration does the soil become saline?

  View Answer play_arrow

• question_answer87)   Does light factor affect the distribution of organisms? Write a brief note giving suitable examples of either plants or animals.

  View Answer play_arrow

• question_answer88)   Give one example for each of the following I. Eurythermal plant species .............. II. A hot water spring organism .............. III. An organism seen in deep ocean trenches............... IV. An organism seen in compost pit.............. V. A parasitic angiosperm ............... VI. A stenothermal plant species ............... VII. Soil organism ............... VIII. A benthic animal............... IX. Antifreeze compound seen in antarctic fish............... X. An organism which can conform...............

  View Answer play_arrow