Biology Exam Preparation

How are covalent and ionic bonds different?

Answer explanation

covalent bonds share electrons.

nonpolar covalent share EQUALLY

polar covalent share UNequally

ionic bonds lose or gain electrons. They DONT SHARE

Define the atomic number and mass number of an atom.

Answer explanation

atomic number is proton

atomic mass is protons and neutrons

Evaluate the properties of carbon that make it unique.

Answer explanation

"has 4, needs 4" electrons, forms covalent bonds (single, double, or triple). straight, branched or chain bonds

Identify patterns in the elements that compose each macromolecule (CHNOPS).

Answer explanation

CHO- carbs

CHO-lipids

CHON - proteins

CHONP - nucleic acids

What is a monomer? What are the monomers of each macromolecule?

Answer explanation

carbs-monosaccharides

protein - amino acids

lipid- not techniqually but fatty acid and glycerol

nucleic acid- nucleotide

What is a functional group? Why is it important?

List the 7 functional groups and their chemical formula. State whether each is polar or nonpolar.

What are the characteristics of life? How would viruses be classified? Justify your answers.

Describe the components of a typical water molecule and explain why it is polar. (Include the molecular & structural formulas). The chemical formula for water is H2O. The hydrogens are slightly positive (because they share their electron with oxygen) and the oxygen is slightly negative(because it has more electrons orbiting around the nucleus than hydrogen does). Because of this unequal sharing, the water molecule has a slight charge of (-) on the oxygen side and a slight charge of (+) ont he hydrogen side. Within the water molecules, the bonds are covalent.

Identify the type of bonds between the atoms of a water molecule and the type of bond that is formed between two water molecules.

Answer explanation

covalent bonds hold the hydrogen and oxygen togther in one molecule. Hydrogen bonds hold two water molecules together (between positive hydrogen of one and negative oxygen of the other)