Answer:
Sperm + egg----- zygote.
Explanation:
During sexual reproduction, a male sperm fuse with female eggs forming a new organism. Male sperm and female eggs have haploid number of chromosomes but when they fuse with each other a zygote will formed having diploid number of chromosomes. The gametes of male and female have haploid number of chromosomes due to meiosis cell division.
Natural levels of nitrate in Minnesota groundwater are usually quite low (less than 1 milligram per liter [mg/L] of nitrate-nitrogen). However, where sources of nitrate such as fertilizers, animal wastes, or human sewage are concentrated near the ground surface, nitrate may seep down and contaminate the groundwater. Elevated nitrate levels in groundwater are often caused by run-off from barnyards or feedlots, excessive use of fertilizers, or septic systems.
Wells most vulnerable to nitrate contamination include shallow wells, dug wells with casing which is not watertight, and wells with damaged, leaking casing or fittings.
Nitrate contamination of a well is often regarded as a first sign of deteriorating groundwater quality.
Answer: [B]: " a muscular foot ".
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"Every mollusk has a head, body, and <u> muscular foot </u> . "
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Hope this helps!
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Answer:
i think it would be A for wild fire, D for flood and E for Tsunami
Explanation: wild fire are one of the most common ways for a secondary succession that can bring change when the environment is disturbed or damaged. For instance, by allowing fast-growing plants to grow and provide a source of food and shelter for many animals to use and eventually draw them back into the ecosystem. Both flooding and tsunamis help push older organisms and other stuff from the environment to create for room for other plants and animals to come and keep the ecosystem healthy and ongoing.
i hope this can help you with your work mate!