TLS Online TPP Program

#Question id: 4744


Assume that long ear lobes in humans are an autosomal dominant trait that exhibits 50% penetrance. A person who is heterozygous for long ear lobes mates with a person who is homozygous for normal ear lobes. What is the probability that their first child will have long ear lobes.

#Unit 8. Inheritance Biology
  1. 1/2                                

  2. 3/4                 

  3. 1/4                

  4. all 

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TLS Online TPP Program

#Question id: 12251

#Unit 10. Ecological Principles

A plant produces flowers that are open through the day and the night. An experimenter places pollen on the stigmas of freshly opened flowers and covers them after pollination to prevent natural pollinators from having access to the flowers. When experimental pollination was carried out during the day, 40% of the flowers yielded fruit. When experimental pollination was carried out during the night, 80% of the flowers yielded fruit. However, when flowers were  kept  open  to  natural  pollination  during  the  day  (covered  at  night),  35%  of  flowers  produced  fruit.  20%  of flowers exposed to natural pollination during the night (covered during the day) produced fruit. Which of the following statements is NOT a plausible explanation of these results ?

TLS Online TPP Program

#Question id: 12252

#Unit 10. Ecological Principles

In a study of interactions between plants, ants and caterpillars, the following experimental treatments were imposed: i) Control (both ants and caterpillars are present); ii) Ant removal; iii) Caterpillar removal; iv) Ant and caterpillar removal. Plus (+) indicates presence and minus (-) indicates absence on plants. The results for plant performance (growth) from this experiment  are shown in the figure below. Plant performance in all treatments were significantly different from each other. Based on these results, which of the following inferences is correct?


TLS Online TPP Program

#Question id: 12253

#Unit 10. Ecological Principles

Both males and females of a fish species show variation in colour. A population of this species consists of 40% blue females, 20% red females, 20% blue males and 20% red males. A researcher catches one fish at random from this population. Given that a male fish is caught, the   probability that it is blue is (Use decimal notation, not fractions or percentage)

TLS Online TPP Program

#Question id: 12254

#Unit 10. Ecological Principles

Assume that the abundance of a species in a community is proportional to the size of its niche. As each new species colonises this community, an existing niche is split. The resultant relative abundances of species in this community will be most uneven

TLS Online TPP Program

#Question id: 12255

#Unit 10. Ecological Principles

The following three panels show the change in population size over time for two species when they are found alone and when they are found together. Which kind of interaction best describes the relationship between the two species?


TLS Online TPP Program

#Question id: 12256

#Unit 10. Ecological Principles

Ant species X preys upon ant species Y. A researcher has the following set of observations regarding the behaviour of species X where aggression signifies a predatory response.

Which of the following statement(s) are correct regarding the behaviour of Species X?

(i)    A glass bead is sufficient to elicit the predatory response.

(ii)   Both chemical and non-chemical cues are involved in the predatory response.

(iii)  Chemical cues are necessary to elicit the predatory response.

(iv) Chemical cues are sufficient to elicit the predatory response