Use the Accompanying Figure to Answer the Following Question

question 23

Multiple Choice

Use the accompanying figure to answer the following question
-Which of the following is an effect of high selenium concentrations in stream water?

• A)Selenium mining companies will want to extract the selenium and thus damage the aquatic ecosystem.
• B)There are no negative effects from selenium, but high selenium levels generally indicate high levels of substances that are harmful.
• C)The selenium will react with potassium isocyanate, resulting in cyanide poisoning of organisms living in the stream.
• D)Selenium causes birth defects in fish.
• E)Selenium reacts with oxygen, thus suffocating fish and other aquatic organisms.

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Definitions:

Neural Connections

the links between neurons in the brain that enable communication through neurotransmitters, forming the basis for all brain functions, including thought and emotion.

Pruning Process

Neural pruning is the process by which extra neurons and synaptic connections are eliminated to increase the efficiency of neuronal transmissions.

Epigenetic Marks

Chemical modifications to DNA and histones that affect gene expression without altering the DNA sequence, often as a response to environmental factors.

Neural Maturation

The process of growth and development of the nervous system, especially in terms of complexity and efficiency of neural pathways.