Review 12

Question 1

Difference b/w prokaryotes and eukaryotes in origins of replication

Answer 1

Prokaryotes have 1 ORI

Eukaryotes have multiple ORI

Question 2

What happens to telomeres during replication?

Answer 2

Get shorter and shorter until can’t get any shorter w/o taking off part of coding DNA => senescent cell

Question 3

Telomerase

Answer 3

Allows cells to escape senescence by telomeres never shortening => cancer

Question 4

Initiation codon

Answer 4

AUG

Question 5

What do snRNA and snRNPs do?

Answer 5

Splice out introns from pre-mRNA

Question 6

Single copy DNA vs. repetitive DNA

Answer 6

Single copy = genes, transcribed/translated, low mutation rate

Repetitive = no genes, not transcribed/translated, high mutation rate

Question 7

Types of supercoils (which is easier to unwind)

Answer 7

Positive supercoil - left-handed, more frequent winding => difficult to unwind

Negative - right handed, easier to unwind

Question 8

Different b/w Type I and Type II topoisomerases

Answer 8

Type I - breaks single strand => release energy

Type II - breaks double strand => requires ATP

Question 9

Describe heterochromatin (eukaryotes or prokaryotes?

Answer 9

Tightly coiled - only eukaryotes

Question 10

Proximal convoluted tubule

Answer 10

Reabsorption of glucose, AA, vitamins, salt, H2O

Question 11

Descending limb of loop of Henle

Answer 11

Permeable to water but not salt => water is reabsorbed

Question 12

Ascending limb of loop of Henle

Answer 12

Permeable to salt but not water => salt is reabsorbed

Question 13

Distal convoluted tubule

Answer 13

Salt reabsorption
Aldosterone response
Waste excretion

Question 14

Collecting duct

Answer 14

Response to aldosterone and ADH

Question 15

Aldosterone

Answer 15

Increases salt reabsorption due to low BP => increase water reabsorption
=> Increased blood volume/pressure (no change in blood osmolarity)
=> Increased K+ secretion

Question 16

Lowest => greatest solute concentration in kidney

Answer 16

Cortex

Question 17

Histone acetylation => coiling or uncoiling?

Answer 17

HAT => uncoiling (euchromatin) => can be accessed by RNA Pol

• Take your hat off => access your head

Question 18

DNA methylation

Answer 18

Gene silencing (more permanent than HDAC)

Question 19

cDNA

Answer 19

mRNA converted back into DNA by RT

• No introns

Question 20

Formula for amount of copies of DNA strand in PCR

Answer 20

2^n

Question 21

Periosteum

Answer 21

Fibrous sheath that surrounds long bones

• Site of attachment to muscle tissues

Question 22

Endochondral vs. intramembranous ossification

Answer 22

Endochondral ossification = replacement of cartilage with bone in long bones

Intramembranous ossification = skull replacement of mesenchyme w/ long bones

Question 23

Gene mapping: what does 18% mean?

Answer 23

18 map units

• If highest % => those two genes are furthest from each other

Question 24

Pulley with 2 strings = (half/double) force and (half/double) distance need to pull

Answer 24

Half force needed

Double distance need to pull

Question 25

Negative torque direction

Answer 25

Rotate clockwise

Question 26

As you get closer to something, perceived frequency ______

Answer 26

Increases (higher pitch) as something gets closer

Question 27

Examples of transverse waves

Answer 27

Transverse = light, EM radiation

Longitudinal = sound, pressure

Question 28

Relation b/w amplitude, energy, and intensity

Answer 28

Greater amplitude = greater energy
Intensity = E/at = Power/area
Greater amplitude = greater intensity

Question 29

Harmonic for open ends

Answer 29

n/2 * lambda

Question 30

Harmonic for closed ends

Answer 30

n(odd)/4 * lambda

Question 31

When light moves to denser medium, it bends towards or away from normal?

Answer 31

Towards normal

Question 32

Amino acids in eukaryotes = L or D?

Prokaryotes

Answer 32

L in eukaryotes

Can be D in prokaryotes

Question 33

AA = S or R?

Answer 33

All are S except cysteine (R) and glycine (achiral)

Question 34

Colligative properties

Answer 34

Physical property of solution dependent on concentration of dissolved particles (but not on their chemical identity)

• Vapor pressure depression
• Boiling point elevation
• Freezing point depression
• Osmotic pressure (but NOT diffusion)