Nucleic Acids

Question 1

NUCLEIC ACIDs

Answer 1

huge oragnic molecules containing ** C / H / O / PO4 -3**

two types
- deoxyribonucleic acid - inherited genetic material
- ribonucleic acid - relays instructions for protein synthesis

monomers = nucleotides

consists of three parts
- nitrogenous base
- pentose sugar
- phosphate group

named b/c discovered in nuclei of cells

Question 2

DNA - nitrogenous base

Answer 2

4 types

purines - larger + double rings
ADENINE [A] + GUANINE [G]

pyrimidines - smaller + single rings
THYMINE [T] + CYTOSINE [C]

Question 3

DNA - nitrogenous base pairs

Answer 3

ADENINE [A] always pairs w/ THYMINE [T]

GUANINE [G] always pairs w/ CYTOSINE [C]

• if only half a strand available, easy to predict the other complementary half

Question 4

DNA - pentose sugar

Answer 4

5 carbon sugar - DEOXYRIBOSE attaches to each base

Question 5

DNA - phosphate group

Answer 5

alternates with pentose sugar to form backbone of DNA strands
- bases project inward
- double stranded helix shape

Question 6

MUTATIONs

Answer 6

any change in nitrogenous base sequence - can cause death of a cell // cancer // genetic defects

Question 7

RIBONUCLEIC ACIDs

Answer 7

• single stranded
• pyrimidine - URACIL [U] instead of
  THYMINE [T]

three types
- messenger RNA (mRNA) - directs protein synthesis
- ribosomal RNA (rRNA) - joins w/ ribosomal proteins to make ribosomes
- transfer RNA (tRNA) - binds to amino acids + holds until it is incorporated during translation