Unit 5 HBio Exam

Clearly describe the general structure of nucleic acids

• Long chainlike formation made of nucleotides (adenine, thymine, cytosine, guanine)

• Circular structure made up of ribosomes

• Single stranded DNA, square like structure

• Single celled organisms

 One sentence that clearly illustrates the relationship between “nucleotide” and “nucleic acid”.

• Nucleotides are the monomer that in quantity make up nucleic acids.

• Nucleic acids make up nucleotides.

• No relationship

• Both are involved in cellular respiration

DNA

•  Genetic code for living organisms like humans, plants and animals

• includes the bases adenine, thymine, guanine, and cytosine

• Double Helix structure

• Single stranded, contains uracil

RNA

• genetic code for viruses

• uses adenine, uracil, guanine, and cytosine (NOT thymine)

• single stranded

• double stranded

Distinguish between the 3’ and 5’ ends of a nucleic acid.

• 5’ end (LEADING) is the end with a phosphate at the top of the strand, the 3’ end (LAGGING) is the side with a sugar at the top of the strand.

• 3' end is the end with a phosphate at the top of the strand, the 5' end is the side with a sugar at the top of the strand

 If 22% of an organism’s DNA contains ADENINE nucleotides, how many THYMINE nucleotides will the DNA contain?  Guanine?  Cytosine?

• 22% THYMINE, 28% GUANUNE, 28% CYTOSINE

• 44% THYMINE, 22% GUANINE, 20% CYTOSINE

• 40% ADENINE, 40%THYMINE, 10% GUANINE, 10% CYTOSINE

• 50% THYMINE

what does helicase do????????!!!!!!!!!!!!!!!!!

• separates dna strands

• breaks apart hydrogen bonds holding the bases together

• glues okazagi fragments together

• primes the strand for DNA polymerase

RNA primase

• prepares the strand by adding a RNA primer so that Polymerase can know where to start doing its job

• breaks apart hydrogen bonds holding bases together

• glues okazaki fragments together

• forms h2o molecules

DNA Polymerase

• accurately adds the complementary bases from RNA onto the DNA strand (Uracil to Adenine, Guanine to Cytosine, ect.)

•  builds the new bases in the 3' to 5' direction on both the leading and lagging strand

• adds an extra codon as a buffer to keep genetic information safe during movement

• breaks apart DNA molecules and releases them into the concentration gradient

ligase

• glues the new bases to the original bases as well as Okazaki fragments together to form a flawless strand. 

• breaks apart hydrogen bonds

• separates DNA strands

• adds deoxyribonucleic acids into carbon dioxide