Ques:Q: What in mammalian lungs, increases the surface area for gas exchange? Choices: - bronchi - thorax - bronchioles - alveoli A:

Ans:alveoli
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Ques:Q: What is the respiratory pigment of almost every vertebrate? Choices: - insulin - plasma - iron - hemoglobin A:

Ans:hemoglobin
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Ques:Q: What promotes cell division and are necessary for growing plants in tissue culture? Choices: - polyamines - auxins - mitochondria - cytokinins A:

Ans:cytokinins
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Ques:Q: What orbits an atoms' nucleus? Choices: - neutrally charged ions - positively charged protons - isotopes - negatively charged electrons A:

Ans:
negatively charged electrons
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