Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
The symbiotic relationship between nitrogen-fixing bacteria and leguminous plants involves complex signaling and structural modifications in the root. Which of the following accurately describes the role of NOD factors in this interaction?
Plant hormones that promote bacterial growth within root nodules
Bacterial signals that trigger root hair curling and cortical cell division
Enzymes produced by the plant to break down bacterial cell walls
Proteins that transport nitrogen from bacteria to plant cells
Which of the following is a micronutrient required for nitrogen fixation in legumes?
Magnesium
Calcium
Molybdenum
Potassium
A farmer implements intercropping with legumes and cereals. The combined yield is significantly higher than the expected sum of individual yields. This increased productivity can be primarily attributed to:
Reduced competition for resources between the two crops.
Enhanced nutrient availability due to nitrogen fixation by legumes.
Allelopathic interactions that stimulate growth in both crops.
Improved soil aeration due to the different root systems.
The process of nitrogen fixation in cyanobacteria occurs within specialized cells called:
Akinetes
Hormogonia
Heterocysts
Carboxysomes
Certain Chlorophyceae demonstrate a unique adaptation to nitrogen-deficient environments. What specialized cellular structure enables this adaptation, and what is its primary function?
Heterocysts; nitrogen fixation
Pyrenoids; carbon fixation
Vacuoles; nutrient storage
Flagella; enhanced motility
The symbiotic association between a fungus and the roots of a higher plant is known as mycorrhiza. Which of the following is NOT a benefit conferred by the fungus to the plant in this association?
Increased absorption of water and minerals
Protection against certain soil pathogens
Enhanced tolerance to drought and salinity
Nitrogen fixation from the atmosphere
Cyanobacteria are known for their ability to:
Produce methane
Fix atmospheric nitrogen
Survive in extreme salinity
Cause diseases in plants
The 'coralloid roots' of Cycas have a symbiotic association with:
Mycorrhizae
Nitrogen-fixing bacteria
Nitrogen-fixing cyanobacteria
Endophytic fungi
A mutation in a legume plant prevents the formation of infection threads during rhizobial symbiosis. Which of the following processes would be MOST directly affected?
Recognition of the rhizobia by the root hairs
Curling of root hairs
Formation of the nodule meristem
Release of bacteria into the host cell cytoplasm
A researcher observes that a particular legume mutant forms nodules, but these nodules fail to fix nitrogen. Which of the following gene mutations is MOST likely responsible?
Mutation in nod genes
Mutation in genes encoding flavonoid biosynthesis
Mutation in nif genes
Mutation in genes encoding leghemoglobin