AP Bio Unit 1: Chapter 2

Methane: molecule? Compound? Molecular formula? Structural formula?

Yes: yes: CH4: H H. C. H H

Carbon dioxide: molecule? Compound? Molecular formula? Structural formula?

Yes: yes: CO2 : O=C=O

Water: molecule? Compound? Molecular formula? Structural formula?

Yes: yes: H2O: O-H | H

Consider the entry in the periodic table for carbon, shown below. 6 C 12. Atomic mass? Atomic number? electrons? Neutrons?

12-6-6-6

Write the chemical shorthand equation for photosynthesis. Label the reactants and the products.

6 CO2 + 6 H2O = C6H12O6 + 6 O2 reactants/ products

What is a hydrogen bond?

A noncovalent attraction between the hydrogen of one molecule with the oxygen and nitrogen of of another molecule. There are no hydrogen bonds in a single molecule.

Which is the only subatomic particle that is directly involved in the chemical reactions between atoms?

Electrons

What is potential energy?

Energy that matter possessed because of its location or structure

What is the difference between an essential element and a trace element?

Essential element: elements that an organism needs to live a healthy life and reproduce. Essential elements comprise about 20-25% of the 92 natural elements. Trace element: Trace elements are required by an organism in only minute quantities. Some trace elements as iron (Fe) are required by all forms of life, whereas others are required only by certain species, such as iodine (I) for vertebrates. Magnesium (Mg)

What is meant by dynamic equilibrium? Does this imply equal concentrations of each reactant and product?

Means that reactions are still going on, but with no net effect on the concentrations of the reactants and products. Equilibrium does not mean that the reactants and products are equal in concentration, but only that their concentrations have stabilized at a particular ratio.

Define anion

Negatively charged ion

Explain the difference between a non polar covalent bond and a polar covalent bond.

Non polar covalent bonds occur between atoms of the same element, the electrons are shared equally, and therefore their polarity is neutral. Polar covalent bonds occur when one atom is bonded to a more electronegative atom, and the electrons of the bond are not shared equally. For example, the bond between hydrogen and oxygen is polar.

What four elements make up 96% of all living matter?

Oxygen, carbon, hydrogen, and nitrogen

Define cation

Positively charged ion

Use morphine and endorphins as examples to explain why molecular shape is crucial in biology.

The precise shape of a molecule is usually very important to its function in the living cell, and crucial in biology because it determines how biological molecules recognize and respond to one another with specificity. Morphine and other opiates have similar shape to endorphins, and can therefore mimic the pain-relieving effect of endorphins by binding to endorphin receptors in the brain.