Answer:
D. A nitrogen base has been added to the DNA molecule.
Explanation:
You can see that the sequence for the nitrogen bases are in the exact same order after the exposure, this rules out A. You can count how many bases there are, 7 before and 8 after so it cannot be B. Lastly, given that they are in the same order as were before and that a base has been added, you can see that no bases were replaced (so not C) and that D is your answer.
Answer:
Soil pollution- Soil pollution is defined as the presence of toxic chemicals in soil
it could pose a threat to humans, etc...
caused by the presence of xenobiotic chemicals
(A xenobiotic is a chemical substance found within an organism that is not naturally produced or expected to be present within the organism.)
or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals or improper disposal of waste.
Air pollution- Air pollution is a mixture of solid particles and gases in the air.
Car emissions, chemicals from factories, dust, pollen and mold spores may be suspended as particles.
Explanation:
Commensalism relationship is shown between cattle egret and cattle.
Usually cattle egrets follow herds of large hoofed mammals such as cattle, buffalo. They eat the insects that have been stirred up by the buffalo as they move. This relationship is commensalism, because the birds benefit but the ungulate is neither harmed nor helped.
The cattle egret and grazing cattle in a close association is a classic example of commensalism. It is a common sight in rural areas where one can see ticks hovering over the cattle. They feed on cattle's blood and hence are harmful to them as they can transmit several diseases. The cattle egret and grazing cattle in a close association is a classic example of commensalism. It is a common sight in rural areas where one can see ticks hovering over the cattle. They feed on cattle's blood and hence are harmful to them as they can transmit several diseases.
To learn more about commensalism , here
brainly.com/question/14224704
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