dna

Question 1

What is the Central Dogma?

Answer 1

Unidirectional flow of info in the cell from DNA through RNA to protein

Question 2

What is involved in the Central Dogma?

Answer 2

Replication (DNA polymerase)
Transcription (RNA polymerase)
Translation (@ ribosome)

Question 3

Structure of bacterial DNA

Answer 3

Double stranded
Circular
covalent bonds between nucleotides
hydrogen bonds between bases

Question 4

structure of bacterial RNA

Answer 4

single stranded

linear, fold up into 2 or 3D shapes

Question 5

replication

Answer 5

process of synthesizing new DNA

MUST occur EVERY time cell divides

Question 6

transcription

Answer 6

synthesis of RNA from parts of the DNA

Question 7

steps of transcription

Answer 7

1-RNA polymerase attaches to DNA, separates the strand
2-Nucleotides w/in cytoplasm base-pair with DNA
3-RNA p. forms bond b/w sugar of 1 nucleotide & P. of another
4-RNA p. moves down strand, open more DNA, more nucleotides b-p
5-Repeat until end of gene
6-RNA p. leaves, DNA zips & mRNA is released into cytosol

Question 8

types of RNA

Answer 8

mRNA; messenger
rRNA; ribosomal
tRNA; transfer

Question 9

mRNA

Answer 9

messenger;
carries info from DNA;
has codons (genetic code)
attaches to 1 or more ribsomes

Question 10

rRNA

Answer 10

ribosomal;
combines w/ proteins to FORM RIBOSOMES
SITE for protein synthesis

Question 11

tRNA

Answer 11

transfer;
in cytoplasm;
picks up AA, brings to mRNA;
anticodon that corresponds with mRNA codon

Question 12

RNA polymerase

Answer 12

large enzyme complex;

synthesizes RNA

Question 13

DNA polymerase

Answer 13

large enzyme complex;

synthesizes DNA

Question 14

what is translation

Answer 14

info contained on mRNA is converted to protein;

protein synthesis

Question 15

steps of translation

Answer 15

1-mRNA & ribosome form complex
2-tRNA w/ AA b-p to mRNA
3-tRNA(2) w/AA(2) b-p to mRNA at 2nd codon
4-ribosome forms covalent (peptide) bond b/w AA(1) & AA(2) simultaneously cutting bond with tRNA
5-tRNA floats away once bond is made b/w AAs & ribosome shifts 1 codon
6-return to step #2 & repeat
7-STOP codon enters ribosome, cuts after last AA.

Question 16

genetic code

Answer 16

Triplet codons
Redundant
Universal

Question 17

Triplet codons (of Genetic Code)

Answer 17

takes 3 nucleotides to encode the info to specify which 1 AA gets incorporated into the protein

Question 18

Redundancy of GC

Answer 18

64 possible codons;

many AA encode by +1 codon

Question 19

Universal GC

Answer 19

almost EVERY organism uses the same translation table;

allows genes to be transferred into different organisms and expressed

Question 20

Mutation

Answer 20

alteration of DNA;
can cause functions to be +/-
ultimate source of genetic diversity (basis for evolution)

Question 21

Point mutations

Answer 21

a single nucleotide is +, -, or changed into a different nucleotide;
affect a single point on the chromosome

Question 22

silent point mutation

Answer 22

change in DNA does NOT cause a change in the AA sequence;

coded for same AA with either codon

Question 23

frame shift point mutation

Answer 23

insertion or deletion causes a shift in the reading frame of mRNA;
can drastically alter a protein, potentially changing every AA after the mutation site

Question 24

Types of genetic diversity

Answer 24

1- conjugation
2- transduction
3- transformation

Question 25

conjugation

Answer 25

donor cell injects DNA into recipient;

F+ cell with pilus–>F- cell w/o pilus = 2 F+ cells with pili

Question 26

transformation

Answer 26

acquire free DNA from extracellular environment, which can be incorporated into chromosomal DNA;
transfer across species

Question 27

transduction

Answer 27

DNA transfer via bacteriophage (infecting virus)

Question 28

Where does transcription take place?

Answer 28

Bacteria- cytoplasm