Download Chemistry of Life Review Sheet Key

Chemistry of Life Review Sheet
Key
Metabolism- sum of the reactions that take place in the cell.
atom- smallest single particle of matter.
isotope- atoms that have the same number of protons but different numbers of neutrons.
ion- atom with + or - charge.
Na+ or O2element- pure substance, one type of atom.
molecule- any cluster of atoms.
H2 or H2O2
compound- any molecule with 2 or more types of atoms. H2O2 or CO2
ionic bond- formed when 2 ions are attracted to one another.
covalent bond- formed when atoms share electron(s).
polar molecule- molecule with positive and negative ends
hydrogen bond- formed between hydrogen of 1 molecule and negative end (usually oxygen) of another
molecule.
dehydration synthesis - a condensation reaction is a chemical reaction in which two molecules or moieties
combine to form one single molecule, together with the loss of a small molecule. When this small
molecule is water, it is known as dehydration synthesis.
hydrolysis - is a chemical reaction or process in which a chemical compound is broken down by reaction
with water, this is the type of reaction that is used to break down polymers. Water is added in this
reaction.
Carbohydrates
1. What 3 elements are found in carbohydrates? C,H,O Ratio 1:2:1
2. What are the building blocks of carbs? Sugars (glucose)
3. What is the difference between a monosaccharide, disaccharide and a polysaccharide?
mono - 1 sugar ring, di - 2 sugar rings, poly - more than 2 sugar rings
4. For each of the following indicate whether it is a monosaccharide, disaccharide or polysaccharide.
a) di
b) mono
c) mono
d) di
e) poly
5. What is the basic molecular formula for a simple sugar? C6H12O6
6. Glucose + glucose = maltose
Glucose + fructose= sucrose
Glucose + galactose= lactose
7. What is the relationship between starch and glucose? Use a labelled sketch to help.
starch
Glucose
8. Structurally cellulose is very similar to starch. However, cellulose is a much stronger molecule due to
the flip flop manner of the bonds linking the glucose monomers. In cellulose there are no SIDE
CHAINS which allow the molecules to lie close to one another giving the opportunity for many
HYDROGEN BONDS to form between adjacent chains.
9. When two glucose are linked together the chemical reaction is called dehydration Synthesis.
10. Explain the difference between amylose and amylopectin. Both are types of starch, amylose is
straight chains of glucose, amylopectin in branched chains of glucose.
11. What is glycogen? A string of 15-24 glucose formed in a muscle or liver cell. Why is it referred to as
animal starch? Plants store excess glucose in the form of starch (stored energy) and animals like
humans store excess glucose in the form of glycogen (stored energy).
1
Lipids
1. What 3 elements are found in lipids? C,H,O
2. What are the 2 main components of a fat molecule? one glycerol and three fatty acids
3. Label the following triglyceride.
glycerol
fatty acids
4. How is dehydration synthesis related to triglyceride formation?
The process of linking a fatty acid chain to a glycerol is called dehydration synthesis and one water
molecule is formed and released.
5. What is the difference between a saturated and an unsaturated fat on three levels: a) structural level
b) physicals property level c) healthy level
a) Saturated - no double bonds between carbons, its "full" of H's. Unsaturated - double bonds between
1 or more carbons, its not "full" of H's
b) Saturated – solid at room temp. Unsaturated – liquid at room temp.
c) Saturated – generally unhealthy. Unsaturated generally healthy.
6. What replaces one of the 3 fatty acid chains on a triglyceride to form a phospholipid? phosphate group
7. Where are phospholipids commonly found? cell membranes
8. What is a trans fat? A very unhealthy unsaturated fat (thought to be linked to cancer and heart
disease) where the hydrogen’s in the hydrocarbon of a fatty acid are on opposite sides of the carbon
chain.
9. Explain the difference between HDL and LDL. HDL – healthy cholesterol (high density) LDL –
unhealthy cholesterol (low density)
Protein
1. What 4 elements are found in protein? C,H,O,N
2. Describe 3 functions of proteins.
i) muscle cells
ii) enzymes
iii) cell organelles largely made of protein
iv) transport bodily fluid (blood)
v) hormones
vi) nutrients (food)
vii) they guide how genes are expressed
3. What are the structural sub-units of proteins? amino acids
4. How many different amino acids are there? 20
5. Label the parts of the amino acid below.
R group
Amino group
Alpha carbon
carboxyl
group
(acid)
2
Nucleic Acid
1. What 5 elements are found in nucleic acid? C,H,O,N,P
2. What are the building blocks of nucleic acids? Nucleotides
3. List the 3 parts of a nucleotide.
i) 5 carbon "pentose" sugar
ii) phosphate group
iii) nitrogen base
4. What makes up the backbone of a nucleic acid? Sugar phosphate backbone
5. What type of bond forms between the base pairs of adjacent nucleic acids? Hydrogen bonds
6. What are the complimentary base pairs for DNA? A with T and C with G
7. Label the 3 parts of a nucleotide on the diagram below.
nitrogen
base
phosphate
group
5 carbon
"pentose"
sugar
3