<span>Cattle and sheep are exposed to lead and zinc when these poisons are in the grass/soil.
Cattle and sheep graze on the grass, and thus they intake these minerals, such as lead and zinc when they come in contact with grass or earth they may eat along with grass. Thus they are exposed to them via eating.
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An indicator species<span> is an organism whose presence, absence or abundance reflects a specific environmental condition. </span>Indicator species<span> can signal a change in the biological condition of a particular ecosystem, and thus may be used as a proxy to diagnose the health of an ecosystem.
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Answer: C) They can contain contaminants that can enter the air during storms or high winds.
Explanation: A is wrong because I got it wrong (Sorry, can't give much explanation there).
B is wrong because water contamination does not directly relate to respiratory health.
D is wrong because fertilizers can impact respiratory health (Explanation seems lack-luster, but I feel like this is common sense).
Hope this helps :)
As you can see in the table presented below, all of the gametophytes have seeds do not form in an enclosed structure and <span>undergo alternation of generations (marked in purple)
The gingkos were widespread in the distant past, but are now presented with only one species with fan-like leaves, the Gingko Biloba. (green)
The gnetophytes have three genera with very different looking species. One of the most iconic ones being the Welwitschia mirabilis often called the wise man's beard. (blue)
The conifers include redwoods, like sequoias and all, have pines as leaves and produce cones. (brown)</span>
The limbic system is responsible for controlling learning and emotional behavior