Biology TEKS 12B

When attached to organic molecules, all of the following functional groups are hydrophilic and polar EXCEPT

• Carboxyl group

• Carbonyl group

• Amino group

• Phosphate group

• Methyl group

Tags

NGSS.HS-PS1-2

Which of the following is true of a 12C molecule and a 14C molecule?

• They have a different number of electrons.

• They have the same number of neutrons.

• They have the same number of protons.

• They have different kinds of atoms.

• They have the same molecular weight.

Tags

NGSS.MS-PS1-1

Which of the groups is correctly matched to its formula?

• Carbonyl-COOH

• Amine-NH3

• Carboxyl-COH

• Phosphate-H2PO4

• Sulfhydryl-SH2

Which of the following functional groups are typically found in an amino acid?

• Amino and hydroxyl

• Amino and amino

• Amino and aldehyde

• Amino and carboxyl

• Carboxyl and keto

Which of the following does not describe an isomer?

• Same molecular formula.

• Different structural formula.

• The numbers of each atom in an isomer remain the same.

• The weight of each atom in an isomer remain the same.

• The number of each atom in an isomer changes from one isomer to the next.

Isotopes of an element

• have the same number of neutrons

• have different numbers of protons

• have essentially different chemical properties

• have different numbers of neutrons

• have different charges

During the winter Lake Michigan freezes over trapping the living organisms under a sheet of solid ice. As the temperature drops the hydrogen bonds between water molecules get locked into a crystalline lattice.

Which of the following can be attributed to the fact that the

bottom of the lake doesn't freeze solid?

• Water expands as it solidifies making ice water less dense than liquid water.

• Hydrogen bonds are constantly breaking and reforming.

• The organisms' metabolic activity produces enough heat to prevent solidification.

• The solutes distributed in the lake have a higher freezing point.

• The hydration shell surround the ice prevents it from extending past the surface.

Tags

NGSS.MS-PS1-4

Which of the following is directly responsible for water being liquid at room temperature?

• Covalent bonds are weaker than hydrogen bonds

• Water has a high heat capacity

• Hydrogen bonds link water molecules together

• Water is a universal solvent

• Water is stable due to strong covalent bonds

Water sustains life on Earth by all of the following properties EXCEPT

• low surface tension from double covalent bonds

• strong capillary action from cohesion and adhesion

• neutral pH from the equal concentrations of H+ and OH- ions

• ability to act as a universal solvent because of the polarity of the H2O molecule

• low density of its solid form because of hydrogen bonds

Tags

NGSS.MS-ESS2-4

All of the following are organic compounds EXCEPT

• lactic acid

• water

• ethanol

• proteins

• fats