ข้อสอบGED Science ชุดที่ 4

Anaerobic fermentation allows cells to generate ATP in the absence of oxygen, producing lactic acid or ethanol as byproducts.

Grass is the producer, grasshopper is the primary consumer, and frog is the secondary consumer (feeding on primary consumers).

RNA uses Uracil (U) instead of Thymine (T) to pair with Adenine (A).

The kidneys filter metabolic waste, electrolytes, and water from the blood to maintain homeostasis and create urine.

Mutualism is a symbiotic relationship in which both participating species gain a fitness benefit (e.g., bees and flowering plants).

Messenger RNA (mRNA) is transcribed from DNA and carries genetic code to ribosomes, where proteins are assembled.

Kinetic energy is calculated as $KE = frac{1}{2} m v^2 = frac{1}{2} (2 text{ kg}) (10 text{ m/s})^2 = 100 text{ J}$.

Solids maintain a rigid, fixed shape and definite volume because their particles are tightly packed in fixed positions.

In a synthesis reaction, two or more simple reactants combine to form a single complex product ($2text{Na} + text{Cl}_2 rightarrow 2text{NaCl}$).

Frequency (measured in Hertz) determines pitch: higher frequencies result in higher-pitched sounds, while amplitude determines loudness.

Neutrons are subatomic particles with zero net electric charge located inside the atomic nucleus alongside protons.

pH values above 7 are basic (alkaline). A pH of 12 indicates a strong base with a high concentration of hydroxide ions ($ ext{OH}^-$).

The troposphere extends from Earth’s surface up to about 8–15 km and contains most atmospheric mass and water vapor, where weather occurs.

Lithification is the geological process where loose, deposited sediments are compacted and cemented together to form solid sedimentary rock.

At divergent boundaries, tectonic plates pull apart from each other, allowing magma to rise from the mantle and create new oceanic crust.

Solar radiation heats Earth’s surface unequally, driving atmospheric circulation, oceanic currents, and weather patterns.

Wind turbines harness the kinetic energy of moving air currents (wind) and convert it into mechanical energy and electrical power.

The independent variable is the single factor intentionally changed or manipulated by the experimenter (soil type).

Radioactive decay follows half-life kinetics, producing a characteristic downward curve that drops rapidly initialy and gradually flattens out.

For a hypothesis to be scientifically valid, it must be possible to design an experiment or observation that could gather empirical evidence to support or refute it.