Which cycle involves nitrogen fixation? A. Carbon cycle B. Nitrogen cycle C. Water cycle D. Rock cycle Explanation: Nitrogen fixation converts N₂ to usable forms.
Which factor increases weathering rate? A. Low temperature B. High rainfall C. Lack of vegetation D. Dry climate Explanation: Water accelerates chemical weathering.
Which ocean zone has no sunlight? A. Photic B. Aphotic C. Littoral D. Neritic Explanation: Aphotic zone lacks sunlight penetration.
Which phenomenon causes tides? A. Solar radiation B. Wind C. Gravitational pull of moon D. Earth rotation only Explanation: Moon’s gravity drives tidal effects.
Which process forms igneous rocks? A. Erosion B. Cooling of magma C. Compaction D. Weathering Explanation: Igneous rocks solidify from molten material.
Which rock is metamorphic? A. Granite B. Basalt C. Marble D. Sandstone Explanation: Marble forms from limestone under heat and pressure.
Which layer of Earth is liquid? A. Inner core B. Outer core C. Mantle D. Crust Explanation: Outer core is molten iron-nickel.
Which ecological interaction benefits both species? A. Parasitism B. Commensalism C. Mutualism D. Competition Explanation: Mutualism benefits both organisms.
Which process produces gametes? A. Mitosis B. Meiosis C. Binary fission D. Budding Explanation: Meiosis produces haploid gametes.
Which organ filters blood? A. Heart B. Kidney C. Liver D. Lung Explanation: Kidneys remove waste from blood.