How does radiometric dating work?
1.Cooling of molten rock produces particular mineral structures that can be used to determine when a crystal formed.
2.Radioisotope decay speeds up over time, so a graph can be made to predict the date.
3.Although ratios of atoms cannot be determined precisely, their half-lives can be used to predict an approximate date that a crystal formed.
4.Fossils older than 60,000 years can only be dated using carbon 14 since all other atoms will have decayed since then.
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The measure of differential survival and reproductive success is termed _____________________
Fill in the blank(s) with correct word
An animal that does NOT maintain a relatively constant internal water concentration as the osmolarity of its environment varies is termed an
A. osmoconformer. B. osmoregulator. C. isoconformer. D. isoregulator. E. hydroconformer.
Chloroplasts in algae are thought to have arisen from which source?
a. Cyanobacteria b. Aerobic bacteria c. Anaerobic bacteria d. Photosynthetic viruses e. Aerobic fungi
ACh regulates neuromuscular junction through (i)______________, which is expressed in skeletal muscle. (ii)_________ is an (iii)_________ of the receptor.
a) (i) ACh nicotinic receptor, (ii) nicotine, (iii) agonist b) (i) ACh muscarinic receptor, (ii) nicotine, (iii) agonist c) (i) ACh nicotinic receptor, (ii) muscarine, (iii) antagonist d) (i) ACh muscarinic receptor, (ii) muscarine, (iii) antagonist