Genetics

Question 1

The Central Dogma

Answer 1

DNA -> RNA -> AA -> Proteins

Question 2

Nucleosome

Answer 2

8 histones + DNA

Question 3

Heterochromatin

Answer 3

Tightly condensed

Question 4

Euchromatin

Answer 4

Lose, transcribable

Question 5

DNA Methylation

Answer 5

Addition of extra methyl group to particular cytosine nucleotides, DNA wound more tightly, transcription impeded

Question 6

Transcription: Initiation

Answer 6

TF bind to promoter on DNA, RNA polymerase unzips DNA creating transcription bubble

Question 7

Transcription: Elongation

Answer 7

One strand of DNA transcribed into complementary DNA strand, RNA polymerase moves 3’ -> 5’ and builds strand 5’ -> 3’

Question 8

Transcription: Termination

Answer 8

RNA polymerase dissociates, Rho proteins help

Question 9

Jacob-Monod Model

Answer 9

Operator, promoter, genes = operon regulated

Lac Operon: decreased glucose=>increased cAMP=>activate CAP protein which bind to CAP site

Question 10

Alternative splicing

Answer 10

Creates variety of RNA from 1 DNA = variety of proteins

Introns removed, exons exit the nucleus to be coded

Question 11

Degenerative code

Answer 11

More than one series of 3 nucleotides may code for the same AA (due to wobble pairing)

Question 12

Start code

Answer 12

AUG (methionine)

Question 13

Stop code

Answer 13

UAA, UAG, UGA

Question 14

Translation

Answer 14

mRNA to proteins, occurs in cytoplasm

Question 15

Translation: initiation

Answer 15

5’ end attaches to small subunit
5’ CAU 3’ settles into Psite
Large subunit joins to form initiation complex

Question 16

Translation: elongation

Answer 16

Ribosome slides down mRNA
New AA to A site
C-terminus to N-terminus in A site
E site prepares for new AA exit

Question 17

Translation: termination

Answer 17

Ends when stop codon is reached
Release factors bind to A site to release chain
Ribosome splits

Question 18

Fates of proteins

Answer 18

Translated in cytosol: functions in cytosol
Translated on Rough ER: functions in membrane bound proteins of nuclear envelope, ER, Golgi, Lysosomes, Plasma membrane, or secreted

Question 19

Mitosis

Answer 19

PMAT

Question 20

Prophase

Answer 20

Chromatin condense into chromosomes
Sister chromatids 
Centrioles move to opposite poles of cell
Nucleolus disappears
Spindle apparatus begins to form

Question 21

Metaphase

Answer 21

Chromosomes align along equator of cell

Question 22

Anaphase

Answer 22

Sister chromatids split at centromeres and segregate to opposite ends of cell

Question 23

Telophase

Answer 23

Nuclear memb and nucleoulus reform
Chromosomes decondense
Cytokinesis completes

Question 24

Point mutation

Answer 24

Single nucleotide change

Base substitution, addition, deletion

Question 25

Silent mutation

Answer 25

Neutral mutation where AA sequence is unchanged

Question 26

Missense mutation

Answer 26

Base substitution changes codon; translation of different AA

Question 27

Nonsense mutation

Answer 27

Change in nucleotide sequence creates a stop codon

Question 28

Frameshift mutation

Answer 28

Insertion/deletion happens in multiples other than 3

Question 29

Translocation of chromosome

Answer 29

Segment of DNA from one chromosome exchanged for segment of DNA on another

Question 30

Inversion of chromosome

Answer 30

Segment of DNA flippled within chromosome

Question 31

Meiosis

Answer 31

Meiosis 1: PMAT 1 Separate homologs to prod 2 1n cells | Meiosis 2: PMAT 2 prod 4 1n sperm or 1 ovum

Question 32

Prophase 1

Answer 32

Homologous chromosomes line up and complete crossover

Question 33

Gene linkage

Answer 33

Genes on same chromosome located close together often cross over together

Question 34

Metaphase 1

Answer 34

Homologues remain attached and move to metaphase plate

Question 35

Anaphase 1

Answer 35

Homologues separate to create 2 haploid cells

Question 36

Telophase 1

Answer 36

Nuclear memb reforms, 2 1n cells created (2° spermaotcyes, 2° oocytes + polar body)

Question 37

Sperm formation

Answer 37

Spermatagonium (2n)->1° spermatocyte (2n)->2° spermatocyte (1n)->Spermatid (1n)->Sperm/spermatazoa (1n)

Question 38

Ovum formation

Answer 38

Oogonium (2n)->1° oocyte (2n)->arrested in P1 until menstruation-> 2° oocyte (1n)-> M2 arrested until fert-> ootid (zygote) (1n)-> ovum (1n)

Question 39

Dihybrid cross ratio

Answer 39

9:3:3:1

Question 40

Hardy Weinberg Principle

Answer 40

P^2+2pq+q^2 = 1 p+q=1 when only 2 alleles p=frequency of dominant alleles q=frequency of recessive alleles