Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
Which condition would MOST significantly inhibit the translocation of sucrose in phloem?
Decreased sucrose concentration in source cells
Increased sucrose concentration in sink cells
Application of a metabolic inhibitor that blocks ATP synthesis in companion cells
Exposure to light
A plant exposed to a fungal toxin exhibits significantly reduced translocation of potassium ions () despite normal transpiration rates. The toxin MOST likely affects which process?
Stomatal opening and closing
Water potential gradient in the xylem
Activity of membrane transport proteins involved in uptake into xylem
Root pressure generation
Researchers observed that inhibiting phloem unloading in a developing fruit resulted in a decrease in sucrose transport to that fruit. However, the transport of certain amino acids to the fruit was unaffected. Which explanation is MOST likely?
Amino acids are transported through the xylem, not the phloem.
Amino acid transport is solely driven by diffusion, unaffected by phloem unloading mechanisms.
Amino acids and sucrose share the same transporters, but amino acids have a higher affinity.
Amino acids are unloaded via a different mechanism than sucrose, potentially utilizing specific transporters independent of sucrose unloading.
A severe combined immunodeficiency (SCID) patient undergoes gene therapy using a retroviral vector to deliver the functional ADA gene. A potential long-term complication specifically associated with this vector type is:
Insertional mutagenesis leading to oncogenesis
Hypersensitivity reaction to the viral vector
Development of neutralizing antibodies against ADA
Rapid clearance of the vector by the immune system
Zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and CRISPR-Cas9 are all tools used in gene editing. What is a key advantage of CRISPR-Cas9 over ZFNs and TALENs?
Higher target specificity and lower off-target effects
Easier design and implementation due to RNA-guided targeting
Ability to target multiple genes simultaneously without modification
Greater stability and longer lifespan within the target cell
Consider a grassland ecosystem. Which of the following changes would MOST likely result in a DECREASE in net primary productivity?
Introduction of a nitrogen-fixing legume species
Increased atmospheric concentration
A controlled burn that removes excess dead biomass
A prolonged drought significantly reducing soil moisture
Which statement BEST explains why inverted pyramids of biomass can exist in aquatic ecosystems?
High respiration rates of consumers
Low consumption rates by herbivores
Rapid turnover rate of producers
Absence of decomposers
In a highly productive aquatic ecosystem experiencing eutrophication, which of the following changes in the trophic structure is LEAST likely to occur initially?
Increased biomass of phytoplankton
Decreased dissolved oxygen levels in the hypolimnion
Increased diversity of primary consumers
Shifts in the dominant species of zooplankton
Which of the following is NOT characteristic of a climax community?
High biomass
Complex food webs
Low species diversity
Stable community structure
The rate of nutrient cycling in an ecosystem is significantly influenced by all of the following EXCEPT:
The temperature and moisture conditions
The abundance and diversity of decomposer organisms
The rate of primary productivity
The wavelength of sunlight reaching the ecosystem
