21. There must be enough sample to test properly.22. Asteroid impact may be a better term than meteorite collision.The impact made the atmosphere opaquer by filling it with dust, and indirectly, smoke, from fires touched off by hot impact debris. Since the atmosphere admitted much less sunlight, photosynthesis and plant productivity were curtailed, with disastrous results, especially for those with the greatest energy requirements, the dinosaurs. Of course, many dinosaurs were killed directly by the impact in areas nearest the Yucatan zero e.g. North America
Answer: An enzyme is a biological catalyst that speeds chemical processes. A substrate is the substance that reacts in contact with an enzyme. Enzymes are specific when reacting with a substrate
Explanation:
Answer:Phenolphthalein is a presumptive test that reacts with the heme molecule present in blood. A positive reaction gives a pink color. While bloodstains normally appear red-brown in color, the color of the substrate or the age of a stain may affect the appearance or visibility of the stain.
Explanation:
True, DNA is DNA, it matters not wether or not it belongs to a plant, you could mix a carrot with a pig (not sure why you would, but you can)
