Unit 2

Question 1

Watson and Crick

Answer 1

“Discovered” the DNA double helix shape in 1953 using xray defraction

Question 2

Rosalind Franklin

Answer 2

Was the one who created the image of DNA, did not receive credit

Question 3

DNA

Answer 3

Codes for proteins, stores info
Command center
Carries info in genes
Codons that allow code to be translated for proteins
Can be copied

Question 4

Nucleotides

Answer 4

Build up DNA (the rungs of the ladder).
Made up of a sugar, phosphate group, and a nitrogenous base (A G C or T)

Question 5

Replication Direction

Answer 5

5’ to 3’ direction

DNA polymerase can only lengthen the chain by attaching to the 3’ end

Question 6

Opposite Polarity

Answer 6

5’ end has free phosphate attached to 5’ carbon of the sugar

3’ end has a free hydroxyl group attached to the 3’ carbon

Question 7

Purines and Pyrimidines

Answer 7

Purines: Adenine and Guanine
Pyrimidines: Cytosine and Thymine

Question 8

Lagging strand

Answer 8

Strand copied into pieces due to the direction of replication and the unzipping direction being opposites

Question 9

Lagging strand

Answer 9

Strand copied into pieces due to the direction of replication and the unzipping direction being opposites

Question 10

Leading strand

Answer 10

continuous strand of replicated dna, replicates in the direction of unzipping (5’->3’)

Question 11

Okazaki Fragments

Answer 11

Pieces of replicated dna that make up the lagging strand

Question 12

DNA packaging Hierarchy

Answer 12

DNA > Nucleosomes > Chromatin > Chromatin Loops > Condensed Chromatin Loops > Chromosome

Question 13

Central Dogma of Biology

Answer 13

One way flow of info from DNA to RNA to Proteins

Question 14

Genetic Code

Answer 14

Set of rules which the info encoded in the base sequences of DNA are translated into amino acids

Question 15

Amino Acids

Answer 15

Building blocks of proteins, only 20 in living organisms

Question 16

Triplet Code

Answer 16

3 letter code that is used to encode the 20 amino acids

Question 17

Codons and the Codon Table

Answer 17

Sets of 3 nucleotides, codon table is a tablet showing what sequences code for what amino acids. is redundant

Question 18

Genes

Answer 18

Physical and functional units of heredity. They occur at specific locations on DNA and composed of base sequences that code for aminos that form proteins

1.5% of the 3 bil bases in human DNA code for proteins

Question 19

Mutations

Answer 19

A change in nucleotide sequences caused by replication errors or mutagens

Question 20

Base substitution Mutations

Answer 20

Replacement of one nucleotide with another. Impact depends on wether it causes an amino acid change. Usually doesnt cause issues

Question 21

Deletion/ Insertion Mutations

Answer 21

Alters the reading frame of the mRNA so the nucleotides are now completely diff codons

causes significant changes

Question 22

Transcription

Answer 22

1st process in constructing a protein

Copies DNA code in the genes, base for base, into mRNA (messenger rna)

Question 23

Translation

Answer 23

2nd process

takes place in ribosomes (containing rRNA) and uses tRNA (transfer rna) to convert the codons into amino acid sequence

Question 24

mRNA

Answer 24

made in nucleus, brought to cytoplasm to give code to make amino acid sequences (proteins) off of

Question 25

tRNA

Answer 25

transfer rna, provides amino acids for mRNA

Question 26

Proteins

Answer 26

series of amino acids that folds to form a molecule that performs a function

Question 27

RNA

Answer 27

Single stranded and has Uracil instead of thymine, and a ribose instead of deoxyribose can fold into shapes that allow it to serve many diff roles