Master NEET Zoology with topic-wise questions. Tailored for NEET students, these questions strengthen your Biology preparation.
Which statement regarding the genetic predisposition to allergies is MOST accurate?
A single gene mutation is usually responsible for most allergic conditions.
Genetic factors play a minimal role in the development of allergies; environmental factors are primarily responsible.
Allergies are strictly inherited following Mendelian patterns of inheritance.
Multiple genes interacting with environmental factors contribute to the development of allergies.
A patient presents with a tumor that shows evidence of loss of heterozygosity (LOH) at a specific locus. Which of the following is the MOST likely explanation for this observation and its significance in cancer development?
Duplication of the mutated allele of an oncogene; Inhibits tumor formation.
Deletion of the normal allele of a tumor suppressor gene; Promotes tumor formation.
Translocation involving a proto-oncogene; Has no effect on tumor formation.
Inversion within a tumor suppressor gene; Suppresses tumor formation.
A new vaccine utilizes a genetically engineered virus-like particle (VLP) displaying a highly conserved epitope from a bacterial pathogen. This VLP does not contain any viral genetic material. Which of the following immune responses is LEAST likely to be induced by this vaccine?
Humoral immunity with the production of neutralizing antibodies.
Activation of B cells and their differentiation into plasma cells.
Cell-mediated immunity targeting infected host cells.
Activation of antigen-presenting cells like dendritic cells.
Herd immunity can be achieved through both natural infection and vaccination. Which of the following factors does NOT significantly influence the threshold for herd immunity against a specific pathogen?
The basic reproduction number (R0) of the pathogen.
The efficacy of the vaccine.
The average lifespan of the pathogen.
The duration of immunity conferred by vaccination or infection.
The presence of homologous structures, like the pentadactyl limb in vertebrates, suggests a common ancestor. However, some scientists argue against this, citing instances where similar structures arise independently. Which of the following BEST refutes this counter-argument and strengthens the evolutionary link implied by homologous structures?
Homologous structures always have identical functions across different species.
Analogous structures, like insect and bird wings, demonstrate convergent evolution and thus invalidate homology.
The fossil record consistently shows a gradual transition in homologous structures over time in all lineages.
Homologous structures often share similar developmental pathways and genetic underpinnings, even when their functions diverge significantly.
While biogeography supports evolution by showing related species in geographically proximate areas, exceptions exist. Which of the following BEST explains the presence of similar flightless birds like ostriches, rheas, and emus on widely separated continents?
Convergent evolution led to the independent development of flightlessness in these birds due to similar selective pressures.
These birds evolved flightlessness independently and then dispersed across vast oceanic distances.
Ancient land bridges allowed these birds to migrate between continents before subsequently losing the ability to fly.
Continental drift, followed by divergent evolution, explains the current distribution of these birds.
The evolution of insecticide resistance in insect populations is often cited as an example of natural selection. However, a counter-argument proposes that resistance pre-exists in a few individuals and simply becomes more frequent. Which observation MOST strongly refutes this counter-argument and supports the role of natural selection?
Insecticide resistance develops more rapidly in populations with high reproductive rates.
Resistant insects often exhibit reduced fitness in the absence of the insecticide.
The specific resistance mechanism, often a change in a target enzyme, arises independently in geographically separated populations exposed to the same insecticide.
The frequency of resistant insects decreases when insecticide application is stopped.
Pseudogenes, non-functional copies of genes, are often considered 'junk DNA.' However, from an evolutionary perspective, they offer valuable insights. Which of the following BEST describes the significance of pseudogenes as evidence for evolution?
They demonstrate that mutations always lead to loss of function and contribute to genetic degradation.
They provide a reservoir of genetic material that can be readily reactivated to generate new functional genes.
Their presence indicates that organisms are actively evolving towards greater complexity.
They represent a record of past gene duplication events and subsequent loss of function, reflecting evolutionary history.
Consider the following statements regarding the process of decomposition in an ecosystem:
I. Decomposition rate is independent of environmental factors like temperature and moisture.
II. Detritivores play a crucial role in fragmenting organic matter, increasing the surface area for microbial action.
III. Decomposition leads to the release of nutrients back into the ecosystem.
IV. Decomposition only occurs in aerobic conditions.
Which of the above statements are correct?
I and II only
II and III only
I, III and IV only
II, III and IV only
