NEET Biology Organisms and Populations MCQs Set B

Question: Which of the following is most appropriately defined?

• a) Commensalism is a relationship in which one species is benefitted and the other is neither benefitted nor harmed.
• b) Parasite is an organism which always lives inside the body of other organism and may kill it
• c) Competition is defined as a process in which the fitness of one species is significantly higher in the presence of another species
• d) Mutualism is a relationship in which one species is benefitted whereas the other is unaffected

Answer: Commensalism is a relationship in which one species is benefitted and the other is neither benefitted nor harmed.

Question: A predator

• a) Acts as conduits for energy transfer across trophic levels
• b) Helps in maintaining species diversity by increasing the intensity of competition among prey species
• c) Is too efficient to overexploits its prey
• d) Shows (+, +) interaction with its prey

Answer: Acts as conduits for energy transfer across trophic levels

Question: Read the following statements and select the correct option w.r.t. poulation attributes

(a) Population density is necessarily measured in numbers
(b) Tiger census is often based on pug marks and fecal pellets
(c) Biomass is not a meaningful measure to know population size.
(d) Size of a population for any species is not a static parameter

• a) b & d
• b) c & d
• c) a & d
• d) a & b

Answer: b & d

Question:  Change in population size equation with prolonged exponential phase can be converted into logistic growth equation by multiplying it with

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Population evolve to maximise their reproductive fitness also called Darwinian fitness with

• a) High r value
• b) Low r value
• c) High K value
• d) None of these

Answer: High r value

Question: Select incorrect statement regarding different population attributes

• a) In age pyramids age distribution of male and females are shown in separate diagrams
• b) Population is a group of individuals multiplying by sexual and asexual reproduction
• c) Size of the population tells a lot about its status in the habitat
• d) Natural selection operates at population level

Answer: In age pyramids age distribution of male and females are shown in separate diagrams

Question: Predation, parasitism and commensalism share a common characteristic i.e.

• a) Interacting species live closely together
• b) Both the interacting species are benefitted
• c) One of the species is benefitted while other is harmed
• d) Both the species belong to same taxonomic group

Answer: Interacting species live closely together

Question: Competition is a rivalry between two or more organisms for obtaining the same resources. It is a type of

• a) Negative interaction
• b) Symbiotic relationship
• c) Positive interaction
• d) Neither positive nor negative interaction

Answer: Negative interaction

Question: Which of the following is incorrect w.r.t. competition?

• a) Only closely related species can show competition
• b) Connel’s field experiment is an example of competitive release
• c) Competitive species may evolve mechanism that promote their co-existance
• d) Resources need not be limiting for competition to occur

Answer:  Only closely related species can show competition

Question: Transition zone between two community is called

• a) Buffer zone
• b) Thermocline
• c) Ecotone
• d) Ecoline

Answer: Buffer zone

Question: An association of individuals of different species living in the same habitat and having functional interactions is

• a) Biotic community
• b) Ecosystem
• c) Ecological niche
• d) Population

Answer: Biotic community

Question: Roots play insignificant role in absorption of water in

• a) Pistia
• b) Pea
• c) Sunflower
• d) Wheat

Answer: Pistia

Question: In which of the following interactions both partners are adversely affected?

• a) Competition
• b) Predation
• c) Parasitism
• d) Mutualism

Answer: Competition

Question:  The following graph depicts changes in two populations (A and B) of herbivores in a grassy field. A possible reason for these changes is that

• a) Population B competed more successfully for food than population A
• b) Population A produced more offspring than population B
• c) Population A consumed the members of population B
• d) Both plant populations in this habitat decreased

Answer: Population B competed more successfully for food than population A

Question: Most animals are tree dwellers in a

• a) Tropical rain forest
• b) Thorn woodland
• c) Coniferous forest
• d) Temperate deciduous forest

Answer: Tropical rain forest

Question: Just as a person moving from Delhi to Shimla to escape the heat for the duration of hot summer, thousands of migratory birds from Siberia and other extremely cold northern regions move to

• a) Keoladeo National Park
• b) Meghalaya
• c) Western Ghat
• d) Corbett National Park

Answer: Keoladeo National Park

Question: A sedentary sea anemone gets attached to the shell lining of hermit crab. The association is

• a) Symbiosis
• b) Commensalism
• c) Ectoparasitism
• d) Amensalism

Answer: Symbiosis

Question: A biologist studied the population of rats in a barn. He found that the average natality was 250, average mortality 240, immigration 20 and emigration 30. The net increase in population is

• a) Zero
• b) 10
• c) 05
• d) 15

Answer: Zero

Question: Cuscuta is an example of

• a) Ectoparasitism
• b) Brood parasitism
• c) Predation
• d) Endoparasitism

Answer: Ectoparasitism

Question: People who have migrated from the planes to an area adjoining Rohtang pass about six months back

• a) Have more RBCs and their haemoglobin has a lower binding affinity of O₂
• b) Have the usual RBC count but their haemoglobin has very high binding affinity to O₂
• c) Are not physically fit to play games like football
• d) Suffer from altitude sickness with symptoms like naussea, fatigue, etc

Answer: Have more RBCs and their haemoglobin has a lower binding affinity of O₂

More Questions..................................................

Question: The logistic population growth is expressed by the equation

• a)

  

• b)

  

• c)

  

• d) dN/dt = rN

Answer:

Question: Large Woody Vines are more commonly found in

• a) Tropical rainforests
• b) Mangroves
• c) Temperate forests
• d) Alpine forests

Answer: Tropical rainforests

Question: Which one of the following is categorised as a parasite in true sense?

• a) Head louse living on the human scalp as well as laying eggs on human hair
• b) Human foetus developing inside the uterus draw nourishment form the mother
• c) The female Anopheles bites and sucks blood from human
• d) The cuckoo (koel) lays its eggs in crow's nest

Answer: Head louse living on the human scalp as well as laying eggs on human hair

Question: Consider the following four conditions (a - d) and select the correct pair of them as adaptation to environment in desert lizards.

The conditions
(a) Burrowing in soil to escape high temperature
(b) Losing heat rapidly from the body during high temperature
(c) Bask in sun when temperature is low
(d) Insulating body due to thick fatty dermis

• a) (a), (c)
• b) (b), (d)
• c) (c), (d)
• d) (a), (b)

Answer: (a), (c)

Question:

• a) Declining population
• b) Stable population
• c) Vanishing population
• d) Expanding population

Answer: Declining population

Question: The figure given below is a diagrammatic representation of response of organisms to abiotic factors. What do a, b and c represent respectively?

• a)

  

  

• b)

  

  

• c)

  

  

• d) None of these

Answer:

Question: Which one of the following is most appropriately defined?

• a) Predator is an organism that catches and kills other organism for food
• b) Amensalism is a relationship in which one species is benefited whereas the other is unaffected
• c) Host is an organism which provides food to another organism
• d) Parasite is an organism which always lives inside the body of other organism and may kill it

Answer: Predator is an organism that catches and kills other organism for food

Question: Which one of the following is one of the characteristics of a biological community?

• a) Stratification
• b) Sex-ratio
• c) Natality
• d) Mortality

Answer: Stratification

Question: Study the four statements (a–d) given below and select the two correct ones out of them

(a) A lion eating a deer and a sparrow feeding on grain are ecologically similar in being consumers
(b) Predator star fish Pisaster helps in maintaining species diversity of some invertebrates
(c) Predators ultimately lead to the extinction of prey species
(d) Production of chemicals such as nicotine, strychnine by the plants are metabolic disorders
The two correct statements are

• a) (a) and (b)
• b) (b) and (c)
• c) (c) and (d)
• d) (a) and (d)

Answer:  (a) and (b)

Question:  A country with a high rate of population growth took measures to reduce it. The figure below shows age-sex pyramids of populations A and B twenty years apart. Select the correct interpretation about them:

• a) "A" is more recent and shows slight reduction in the growth rate.
• b) None of these
• c) "A" is the earlier pyramid and no change has occurred in the growth rate
• d) "B" is more recent showing that population is very young.

Answer: "A" is more recent and shows slight reduction in the growth rate.

Question: Quercus species are the dominant component in

• a) Temperate deciduous forests
• b) Scrub forests
• c) Tropical rain forests
• d) Alpine forests

Answer: Temperate deciduous forests

Question: What is true about the isolated small tribal populations?

• a) There is a decline in population as boys marry girls only from their own tribe
• b) There is no change in population size as they have a large gene pool
• c) Hereditary diseases like colour blindness do not spread in the isolated population
• d) Wrestlers who develop strong body muscles in their life time pass this character on to their progeny

Answer: There is a decline in population as boys marry girls only from their own tribe

Question:  Consider the following four statements (a - d) about certain desert animals such as kangaroo rat.

(a) They have dark colour and high rate of reproduction and excrete solid urine.
(b) They do not drink water, breathe at a slow rate to conserve water and have their body covered withthick hairs.
(c) They feed on dry seeds and do not require drinking water.
(d) They excrete very concentrated urine and do not use water to regulate body temperature.
Which two of the above statements for such animals are true?

• a) c and d
• b) b and c
• c) c and a
• d) a and b

Answer: c and d

Question: If the mean and the median pertaining to a certain character of a population are of the same value, the following is most likely to occur

• a) A normal distribution
• b) A T-shaped curve
• c) A skewed curve
• d) A bi-modal distribution

Answer: A normal distribution

Question: The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the season. What does this show?

• a) Its population growth curve is of J-type.
• b) The food plants mature and die at the end of the rainy season.
• c) S-shaped or sigmoid growth of this insect.
• d) The population of its predators increases enormously

Answer: Its population growth curve is of J-type.

Question: Geometric representation of age structure is a characteristic of

• a) Population
• b) Landscape
• c) Biotic community
• d) Ecosystem

Answer: Population

Question: A high density of elephant population in an area can result in

• a) Intra specific competition
• b) Predation on one another
• c) Inter specific competition
• d) Mutualism

Answer: Intra specific competition

Question: Niche overlap indicates

• a) Sharing of one or more resources between the two species
• b) Mutualism between two species
• c) Two different parasites on the same host
• d) Active co-operation between two species

Answer: Sharing of one or more resources between the two species

Question: Annual migration does not occur in the case of

• a) Salamander
• b) Arctic tern
• c) Siberian crane
• d) Salmon

Answer: Salamander

Question: The formula for exponential population growth is

• a) dN/dt = rN
• b) rN/dN = dt
• c) dN/rN = dt
• d) dt/dN = rN

Answer: dN/dt = rN

Question:  There exists a close association between the alga and the fungus within a lichen. The fungus

• a) Provides protection, anchorage and absorption for the alga
• b) Fixes the atmospheric nitrogen for the alga
• c) Provides food for the alga
• d) Releases oxygen for the alga

Answer: Provides protection, anchorage and absorption for the alga

Question: Which one of the following pairs is mismatched?

• a) Prairie — epiphytes
• b) Coniferous forest — evergreen trees
• c) Savanna — Acacia trees
• d) Tundra — permafrost

Answer: Prairie — epiphytes

Question: Animals have the innate ability to escape from predation. Examples for the same are given below. Select the incorrect example

• a) Poison fangs in snakes
• b) Colour change in chameleon
• c) Melanism in moths
• d) Enlargement of body size by swallowing air in puffer fish

Answer: Poison fangs in snakes

Question: At which latitude, heat gain through insolation approximately equals heat loss through terrestrial radiation ?

• a) 40° North and South
• b) 66° North and South
• c)

  

• d) None of these

Answer: 40° North and South

Question: The basic unit of study in Ecology is

• a) Organism
• b) Community
• c) Species
• d) Population

Answer: Organism

Question: The ‘niche’ of a species is meant for

• a) Habitat and specific functions of a species
• b) Specific place where an organism lives
• c) Specific species function and its competitive power
• d) None of these

Answer: Habitat and specific functions of a species

Question: In which one of the following habitats does the diurnal temperature of soil surface varies most?

• a) Desert
• b) Grassland
• c) Forest
• d) Shrub land

Answer: Desert

Question: The abundance of a species population within its habitat, is called

• a) Niche density
• b) Absolute density
• c) Regional density
• d) Relative density

Answer: Niche density

Question:  Plants such as Prosopis, Acacia and Capparis represent examples of tropical

• a) Thorn forests
• b) Grass lands
• c) Evergreen forests
• d) Deciduous forests

Answer: Thorn forests

Question: What is true for individuals of same species?

• a) Interbreeding
• b) Live in same niche
• c) Live in same habitat
• d) Live in different habitat

Answer:  Interbreeding

Question: Which one of the following pairs is correctly matched?

• a) Streamlined body - aquatic adaptation
• b) Uricotelism - aquatic habitat
• c) Parasitism - intra-specific relationship
• d) Excessive perspiration - xeric adaptation

Answer: Streamlined body - aquatic adaptation

Question: More than 70% of world’s freshwater is contained in

• a) Polar ice
• b) Antartica
• c) Glaciers and mountains
• d) Greenland

Answer: Polar ice

Question: Which of the following are likely to be present in deep sea water?

• a) Archaebacteria
• b) Saprophytic fungi
• c) Blue-green algae
• d) Eubacteria

Answer:  Archaebacteria

Question: Benthic organisms are affected most by

• a) Sediment characteristics of aquatic ecosystems
• b) None of these
• c) Light reaching the forest floor
• d) Surface turbulence of water

Answer: Sediment characteristics of aquatic ecosystems

Question: Which one of the following is not a parasitic adaptation?

• a) Loss of reproductive capacity
• b) Development of adhesive organs
• c) Loss of unnecessary sense organs
• d) Loss of digestive organs

Answer: Loss of reproductive capacity

Question: In a lake, phytoplankton grow in abundance in

• a) Limnetic zone
• b) Profundal zone
• c) Benthic region
• d) Littoral zone

Answer: Limnetic zone

Question: Littoral zone is located along the

• a) Sea
• b) High mountains
• c) Rivers
• d) Deser

Answer: Sea

Question: The age pyramid with broad base indicates

• a) High percentage of young individuals
• b) Low percentage of young individuals
• c) High percentage of old individuals
• d) A stable population

Answer: High percentage of young individuals

Question: A population growing in a habitat with limited resources shows four phases of growth in the following sequence

• a) Lag phase – acceleration – deceleration – asymptote
• b) Asymptote – acceleration – deceleration – lag phase
• c) Acceleration – deceleration – lag phase – asymptote
• d) Acceleration – lag phase – deceleration – asymptote

Answer: Lag phase – acceleration – deceleration – asymptote

Question: Sigmoid growth curve is represented by

• a) dN/dt = rN (1 – N/K)
• b) dN/dt = 1 – N/K
• c) dN/dt = rN
• d) Nt = No + B + I – D – E

Answer:  dN/dt = rN (1 – N/K)

Question: Two opposite forces operate in the growth and development of every population. One of them is related to the ability to reproduce at a given rate. The force opposite to it is called

• a) Environmental resistance
• b) Mortality
• c) Fecundity
• d) Biotic control

Answer: Environmental resistance

Question: The growth curve of bacterial population in lab is plotted against time. What will be the shape of graph?

• a) J-shaped
• b) Hyperbolic
• c) Sigmoid
• d) Ascending straight line

Answer: J-shaped

Question:  Certain characteristic demographic features of developing countries are

• a) High fertility, low or rapidly falling mortality rate, rapid population growth and a very young age distribution
• b) High fertility, high density, rapidly rising mortality rate and a very young age distribution
• c) High infant mortality, low fertility, uneven population growth and a very young age distribution
• d) High mortality, high density, uneven population growth and a very old age distribution

Answer: High fertility, low or rapidly falling mortality rate, rapid population growth and a very young age distribution

Question: Praying mantis is a good example of

• a) Camouflage
• b) Warning colouration
• c) Mullerian mimicry
• d) Social insects

Answer: Camouflage

Question: Which type of association is found in between entomophilous flower and pollinating agent?

• a) Co-evolution
• b) Cooperation
• c) Commensalism
• d) Amensalism

Answer:  Co-evolution

Question: Unrestricted reproductive capacity in a population is called as

• a) Biotic potential
• b) Fertility
• c) Carrying capacity
• d) Birth rate

Answer: Biotic potential

Question: What is a keystone species?

• a) A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community’s organization and survival
• b) A common species that has plenty of biomass, yet has a fairly low impact on the community’s organization
• c) A rare species that has minimal impact on the biomass and on other species in the community
• d) A dominant species that constitutes a large proportion of the biomass and which affects many other species

Answer: A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community’s organization and survival

Question: In which one of the following pairs is the specific characteristic of a soil not correctly matched?

• a) Black soil - Rich in calcium carbonate
• b) Terra rosa - Most suitable for roses
• c) Laterite - Contains aluminium compound
• d) Chernozems - Richest soil in the world

Answer: Black soil - Rich in calcium carbonate

Question: According to Darwin, the organic evolution is due to

• a) Interspecific competition
• b) Competition within closely related species
• c) Reduced feeding efficiency in one species due to the presence of interfering species
• d) Intraspecific competition

Answer: Interspecific competition

Question: Rise in the temperature and air humidity can be observed from

• a) Poles to equator region during latitudinal transition
• b) Equator towards polar region
• c) Plains to mountain top during altitudinal movement
• d) More than one option is correct

Answer: Poles to equator region during latitudinal transition