Consider the following statements about the carbon cycle: 1. Photosynthesis removes CO₂ from the atmosphere. 2. Respiration and combustion return CO₂ to the atmosphere. 3. Decomposition releases CO₂. Which of the above is/are correct? MCQ with Answer and Explanation

Explanation:
ATP synthase (Complex V) uses the proton gradient generated by the electron transport chain to phosphorylate ADP to ATP. Cytochrome oxidase is Complex IV, succinate dehydrogenase is part of the Krebs cycle and Complex II, citrate synthase is in the Krebs cycle.

Explanation:
All chordates, at some point during their larval or adult stages, possess three key features: a dorsal hollow nerve cord, a notochord (a flexible rod supporting the body), and pharyngeal slits. The notochord may be replaced by a vertebral column in vertebrates. Arthropods have a ventral nerve cord and open circulatory system.

Explanation:
Fleming accidentally discovered penicillin in 1928 when a mold contaminant (later identified as Penicillium notatum/now Penicillium chrysogenum) inhibited bacterial growth. This led to the first widely used antibiotic. Aspergillus species produce some toxins and acids, Saccharomyces is yeast, Agaricus bisporus is the common mushroom. Penicillin acts by disrupting bacterial cell wall synthesis.