Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
A researcher observes an isolated system containing complex organic molecules undergoing spontaneous self-assembly into membrane-bound structures. These structures exhibit rudimentary metabolism but no reproduction or heritability. Which characteristic of life is the MOST significant barrier preventing these structures from being classified as living organisms?
Metabolism
Cellular organization
Reproduction and growth
Adaptation
Polyhydroxybutyrate (PHB) granules in prokaryotes serve primarily as a reserve of:
Nitrogen
Phosphorus
Carbon and energy
Sulfur
A researcher observes a eukaryotic cell lacking functional peroxisomes. Which of the following metabolic processes would be MOST directly affected?
Glycolysis
Breakdown of long-chain fatty acids
Synthesis of proteins
Replication of DNA
A dormant seed of a desert plant exhibits an extremely low metabolic rate. Which of the following biochemical changes contributes MOST significantly to this state?
Increased gibberellin biosynthesis and rapid cell division
High abscisic acid (ABA) levels and dehydration of cellular components
Elevated ethylene production and fruit ripening processes
Increased cytokinin concentration and enhanced protein synthesis
Which organelle contains enzymes that convert fatty acids into sugars, especially in germinating seeds?
Peroxisomes
Glyoxysomes
Lysosomes
Ribosomes
The methanogens, a unique group within Archaebacteria, are characterized by their ability to:
Perform photosynthesis using bacteriochlorophyll
Produce methane as a metabolic byproduct
Fix atmospheric nitrogen in aerobic conditions
Survive extreme high pH environments
The 'glycolate metabolism' pathway in some Chlorophyceae involves a unique organelle. Which one is it, and what is its primary function in this context?
Peroxisome; glycolate oxidation
Mitochondrion; ATP synthesis
Chloroplast; CO2 fixation
Golgi apparatus; protein modification
Which statement regarding the biosynthesis of cholesterol is INCORRECT?
HMG-CoA reductase is the rate-limiting enzyme in cholesterol biosynthesis.
The process occurs primarily in the liver.
NADPH provides the reducing equivalents for the biosynthesis of cholesterol.
Oxygen is directly involved in the condensation of isoprene units to form squalene.
Glycogen, the primary storage polysaccharide in animals, exhibits a highly branched structure. Which of the following best explains the significance of this branching for its function?
Branching increases the structural rigidity of glycogen, enabling it to form strong fibers.
Branching decreases the osmotic pressure exerted by glycogen within cells.
Branching facilitates the transport of glycogen across cell membranes.
Branching allows for rapid hydrolysis by providing multiple sites for enzyme action, crucial for quick energy release.