Answer the following question given this paragraph: There are 20 common amino acids in proteins. There are 64 possible codons, more than enough to code for the 20 amino acids. The genetic code is shown in Figure below . To see how scientists cracked the genetic code, go to this link: http://www. dnalc. org/view/16494-Animation-22-DNA-words-are-three-letters-long-. html . Q: Proteins include 20 common types of what compounds? A:
OPTIONS:
- mitochondria
- rna acids
- dna
- amino acids
amino acids

Answer the following question given this paragraph: When we run a reaction to produce a gas, we expect it to rise into the air. Many students have done experiments where gases such as hydrogen are formed. The gas can be trapped in a test tube held upside-down over the reaction. Carbon dioxide, on the other hand, sinks when it is released. Carbon dioxide has a density greater that air, so it will not rise like these other gases would. Q: Carbon dioxide does not rise like other gases because it has a density greater than what? A:
OPTIONS:
- gravity
- light
- water
- air

Answer: air

Question: Answer the following question given this paragraph: The sodium-potassium pump is an active transport pump that exchanges sodium ions for potassium ions. Q: The sodium-potassium pump is an active transport pump that exchanges sodium ions for what? A:
OPTIONS:
- nitrogen ions
- oxygen ions
- chlorine ions
- potassium ions
Answer: potassium ions

input with options: Answer the following question given this paragraph: Q: Acting like drawstrings to close off the alimentary canal, what regulates the passage of material between compartments? A:
OPTIONS:
- intestine
- hamstring
- uterus
- sphincter
output: sphincter

Q: Answer the following question given this paragraph: Covalent bonds are chemical bonds between atoms of nonmetals that share valence electrons. In some covalent bonds, electrons are not shared equally between the two atoms. These are called polar covalent bonds. The Figure below shows the polar bonds in a water molecule (H 2 O). The oxygen atom attracts the shared electrons more strongly than the hydrogen atoms do because the nucleus of the oxygen atom has more positively charged protons. As a result, the oxygen atom becomes slightly negative in charge, and the hydrogen atoms become slightly positive in charge. For another example of polar bonds, see the video at this URL: http://www. youtube. com/watch?v=1lnjg81daBs. Q: What are chemical bonds between atoms of nonmetals that share valence electrons called? A:

OPTIONS:
- electron bonds
- ionic bonds
- gravitational bonds
- covalent bonds

A: covalent bonds

Answer the following question given this paragraph: There are three components that make up an electrochemical reaction. There must be a solution where redox reactions can occur. These reactions generally take place in water to facilitate electron and ion movement. A conductor must exist for electrons to be transferred. This conductor is usually some kind of wire so that electrons can move from one site to another. Ions also must be able to move through some form of salt bridge that facilitates ion migration. Q: What allows the electrons to move in an electrochemical system. A:
OPTIONS:
- conduction
- mass
- magnetism
- conductor
conductor