Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Bio 151 > exam 2 > Flashcards

exam 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

x ray crystallography

A

makes DNA into crystals and shine x-ray light through to find structure and functions of biological molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

DNA double helix

A

nucleotides covalently linked into strands that contain any sequences of nucleotides in any order; complementary strand binds through H bonds and twisted into double helix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

purine nucleotides

A

A and G

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

pyrimidine nucleotides

A

T and C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

how are complementary base pairs linked

A

hydrogen bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

DNA strand directions

A

antiparallel; 5’ end of one stand line up with 3’ end of the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

3’ end

A

3 carbon bonded to phosphate; OH group on end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

5’ end

A

5 carbon bonded to phosphate group; phosphate on the end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what links together nucleotides in the strand

A

phosphodiester bonds (phosphate-sugar-phasphate-sugar)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

DNA replication

A
  • separate 2 strands of DNA
  • used as template for new strand
  • new strand create; reverse complement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what kind of model does DNA replication follow?

A

semi conservative model

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

DNA polymerase

A

enzyme that matches complementary nucleotides to template and binds new strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

central dogma

A

base pair matching used for information flows from dna -> rna -> protien

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

DNA polymerase

A

dna replication enzyme that matches complementary nucleotides to template and builds new strand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

which direction does dna polymerase build new strand

A

5’ -> 3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

where was is template strand read

A

3’ -> 5’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

helicase

A

enzyme that breaks hydrogen bonds between nitrogenous bases of double stranded dna (unzips)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

replication fork

A

area where double helix is opened and where the replication of DNA will actually take place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

replication bubble

A

formed because 2 helicase working in opp directions -> 2 replication forks -> creates bubble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

origin of replication

A

specific dna sequence where helicases and polymerases start replication; proteins distinguish by specific nucleotide sequence
*creates neg feedback loop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

origin of replication; prokaryotes

A

1 origin of replication bc small circular chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

origin of replication; eukaryotes

A

many origins of replication because larger linear chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

supercoiling

A

winding up of dna strands (problem separating the replicates)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

topoisomerase

A

enzyme that cuts strands of dna allowing them to unwind, then rejoins them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

rna polymerase

A

brin in first rna nucleotide for replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is the problem with dna polymerase?

A

it cannot start dna replication on its own; only can elongate the nucleotide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

primase

A

builds short rna primer that dna polymerase can add to
*type of rna polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

dna ligase

A

joins the 2 replicated dna fragments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

replication of the leading strand

A

chases helicase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

replication of the lagging strand

A

fragments created bc replication keeps stopping and starting since polymerase can only work 5’ -> 3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

tolemere

A

end of linear chromosome
*only in eukaryotes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

centromere

A

middle of a linear chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

overhang

A

telomere is single stranded which is less stable -> if nothing done then cell looses nucleotides every division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

tolemerase

A

enzyme that adds nucleotides to template strand where the extended rna primer overhang can bind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what cells have tolemerase

A

cells that replicate often; germ line cells (reproductive), stem cells and cancer cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what factors make tolemers get shorter

A

stress and age
*skin cells don’t have telomerase -> aging?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

dna replication in lab

A

1) get bacteria to grow plasmid dna
or
2) dna replication in test tube via pcr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

polymerase chain reaction (pcr)

A

amplifies part of a dna strand; used template dna, mixture of dNTP’s (triphosphate dna nucleotides) and dna primers; heat cycles and amplify

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

mRNA

A

messenger rna; used to make protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

transcription

A

process of using dna template to make rna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

transcription: amplification

A

make many mRNAs from 1 gene (template region of DNA)
*many proteins made from 1 mRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

transcription: control

A

can change/ control whether or not to make mRNA from DNA and/or how much is translated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

transcription: evolution

A

earliest cells might not have had dna; mrna directly made proteins
*rna world hypothesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

transcription requirements

A

rna polymerase (so no primer needed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

dna-rna binding in transcription is…

A

temporary (dna only used as template)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

how many mrna can be made from 1 dna template

A

many!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

transcription unit

A

a region of dna used as a template for a type of rna ; from promoter to terminator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

how many transcription units per chromosome

A

100s-1000s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

genes

A

regions of dna that define the coding info for a protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

promoter dna

A

nucleotides bound by rna polymerase that signify the starting point of the transcription unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

transcription factors

A

proteins that bind to dna and recruit rna polymerase/ give it directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

tata box promoter

A

recruits and directs dna polymerase; located upstream of where transcription starts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

terminator dna

A

where transcription stops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

transcription in prokaryotes

A

no nucleus/ membrane bound sections to move mRNA in and out of; translation begins before transcription ends (5’ end once made attaches to ribosome)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

polyribosome

A

ribosome attached to an mRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

transcription in eukaryotes

A

transcription in nucleus separated from translation; nucleus -> cytoplasm -> ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

why is mRNA modified in eukaryotes

A

to help with stability and export out of the nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

mRNA modifications

A
  • 5’ cap: modified nucleotide 5’ - 5’
  • poly- A tail: binds to proteins at 3’ end to stabilize, recognize/mark and export from nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

primary transcript of mRNA

A

mRNA before modifications (5’ cap and poly-A tail)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

rna processing

A

removal of non coding introns and splicing together of remaining exons (coding regions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

introns

A

non coding regions of rna that are spliced out
-thinner than exons
-spliced out at splice site/ exon- intron junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

exons

A

coding regions of rna (thicker than introns)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

spliceosome

A

protiens and small nuclear rna (snRNA) that remove introns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

what are snRNAs

A

ribozymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

alternative splicing

A

rna keep different exons in different cells -> get diff mRNA proteins from same dna template

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

how can ribosomes be isolated

A

-can be seen by e- microscope
-cell fractionalization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

cell fractionlization

A

separating cell components by density; create density gradient using sugar solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

ribosomes

A

cell structure that makes proteins;
-made of ribosomal rna (rRNA) and proteins
-have large and small subunits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

codon

A

nucleotide triplet in mrna that amino acids are coded with

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

what way do ribosomes build and read amino acids

A

build: 5’ -> 3’
read: 3’ -> 5’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

experiment that discovered codons

A

feed radioactive amino acids to cell-> look what radioactive proteins were made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

start codon; and what does it match with?

A

AUG/ ATG
*matches with initiator tRNA anticodon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

stop codons

A

TAA, TAC, TGA
*nonsense codons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

release factor

A

protein that bonds to stop condon; releases polypeptide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

codon steps

A

1) linear sequence mrna has triplet codons
2) ribosome attaches and reads mrna codon sequence
3)recognize triplet -> bring in right amino acids (reverse complement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

adaptors

A

tRNA (transfer rna) that binds to mrna codon and amino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

anticodon

A

reverse complement rna that binds to codon in mrna -> brings in attached amino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

aminoacyl trna

A

amino acid bound to trna amino acid attachment site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

aminoacyl trna synthases

A

enzymes that attach amino acids to the correct tRNA.
*specific enzyme for each type of trna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

untranslated regions (utr)

A

5’ utr: before start codon
3’ utr: after stop codon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

translation in prokaryotes

A

1 mrna can code for several different proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

operons

A

several consecutive start/stop regions in 1 mrna; cluster of genes transcribed from the same promoter to give a single mRNA carrying multiple coding sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

what recognized intron-exon splice sites

A

small nuclear rna (snRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

info for nucleotide sequence for snRNA comes from….?

A

dna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

mutation

A

dna nucleotide changes that lead to permanent, heritable changes in genome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

what causes mutations (3)

A

1) bad replication; mistakes in dna polymerase proofreading
2) chemical/ radiation damage to bases/ dna strands
3) viruses and transposable elements that hijack/ jump around dna damaging it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

point mutations

A

change in or gain/loss of single nucleotide base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

point mutations: synonymous mutation

A

mutated nucleotide that codes for same amino acid -> no change in protein/ silent mutation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

point mutations: missense mutation

A

change nucleotide that leads to the wrong amino acid being made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

point mutations: nonsense mutation

A

change in nucleotide sequence makes stop codon -> incomplete protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

point mutations frameshift mutation

A

deletion or insertion of nucleotide -> changes how codon triplets are read
*frame stays the same if 3 nucleotides added together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

mutations in non coding regions

A

impacts mRNA made
*could disrupt stop codon, protomer/terminator dna, splice sites, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

transcriptional regulation

A

use transcription factor proteins to help or inhibit dna polymerase to increase or decrease transcription of nearby genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

example of gene regulation: Lac operon

A

*beta galacto sidase breaks down lactose -> glucose
*repressor protein binds to operator site -> repress

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

how can lactose be broken down into glucose

A
  • presence of lactose; allosterically binds to repressor transcription factor to allow for transcription
    *other transcription factors act;; CRP or cyclic AMP (cAMP)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

CRP

A

activator transcription protein; active when low levels of glucose (bring lactose in even when repressor is repressing)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

cAMP

A

non protein molecule; second messenger whose levels of abundance carry info about how much glucose there is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

cAMP levels and glucose

A
  • glucose high = cAMP low
  • glucose low = cAMP high (signal for more lactose to be broken down)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

enhancer dna

A

transcription factor that stimulates transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

silencer dna

A

transcription factor that represses transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

do transcription factors have to be close to promoter to impact transcription

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

chromatin remodeling

A

change chromosome shape by wrapping dna into nucleosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

what carries out chromatin remodeling

A

histone proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

impact of chromatin remodeling

A

more densely packed dna makes it harder to transcribe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

what do acetyl groups on histone do

A

cause less winding of dna, therefore more transcription
*taking off acetyl groups silences transcription/ gene expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

dna modifictions

A

change gene expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

dna methylation

A

adding a methyl group to silence region gene expression
*temporary and does not change genetics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

epigenetic change

A

changes in transcription factors that do not genetically modify/ alter nucleotide sequence
*stays consistent through cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

microRNA

A

binds to mRNA after transcription to trigger destruction or to block translation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

what 2 things can mutations impact

A

1) can change recognition sites for transcription factor binding (promoter, enhancer, silencer dna)

2) can change the transcription factor itself

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

chromatin

A

strands of chromosomes (dna, histones, transcription factors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

nucleolus

A

site of rRNA synthesis in the middle of the nucleus; not membrane bound

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

inner and outer envelopes

A

2 lipid bilayers of the nucleus perforated by nuclear pores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

how to transport proteins to diff parts of the cell

A

use signal sequence -> bind to carrier protein for specific part of cell -> transport protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

importin

A

a protein that imports proteins bound to it into nucleus

116
Q

exportin

A

protein that shuttles a protein out of the nucleus

117
Q

nuclear import signal sequence

A

specific amino acid sequence on a protein being transferred that binds to importin via lock and key interaction

118
Q

endoplasmic reticulum

A

network of membrane enclosed tubes/dishes that is continuous with the outer nucleus membrane

119
Q

smooth er

A

-has no ribosomes (so not involved with protein synthesis)

-has enzymes that synthesize lipids, steroids, carbohydrates

  • Calcium ion storage place (pumps in with membrane pumps)
120
Q

rough er

A

has ribosomes -> synthesises proteins

121
Q

rough er secretion

A

secretion signal sequence on protein binds to SRP receptor -> secretion by exocytosis -> ER lumen

122
Q

where do proteins go after the rough er and how do they get there

A

they go to the golgi apparatus via vesicals

123
Q

golgi apparatus

A

stacks of flattened membrane that modifies/ process proteins

124
Q

golgi apparatus cis face

A

innermost face

125
Q

golgi apparatus trans face

A

outermost face

126
Q

how does the golgi modify proteins

A
  • cleave; split into 2
  • covalently link other proteins together; disulfide bonds
    -glycosylation: adding sugars to protein
127
Q

how do vesicles know where to go

A

proteins on outside of vesical

128
Q

lysosome

A

digestive enzymes that break up macromolecules; mini stomach in cell

129
Q

lysosome pH

A

acidic inside of lysosome so things can be broken down; H+ pumps move H+ into lysosome from cytosol

130
Q

how are vesicles moved

A

moved by motor proteins along the cytoskeleton

131
Q

cytoskeleton

A

intracellular roads and fibers made up of many proteins

132
Q

microtubules

A

thick hollow tubes in cytoskeleton

133
Q

what are microtubules made of

A

alpha and beta tubulin proteins

134
Q

how do microtubules move things

A
  • lengthening and shortening
    -motor proteins
    -slide past each other using cilia (lots of short structures) and flagella (one long structure)
135
Q

what motor proteins do microtubules use

A

kinesin or dynein

136
Q

cilia and flagella

A

bendable projections of membrane organized into ring with a 9-fold array of stable doublet microtubules; pairs connected by dynein motor protein

137
Q

what do microtubules do during cell division

A

move chromosomes

138
Q

microfilaments and function

A

finest/ thinnest part of the cytoskeleton used for:
-rapid cell shape change
- intracellular movements (* cytoplasm streaming)
- muscle contraction

139
Q

what are microfilaments made of

A

double helix made of actin proteins; shortened and lengthened by actin removal

140
Q

microfilaments motor proteins

A

myosins

141
Q

how do microfilaments move things

A

-motor proteins
-move things along microfilaments
-slide microfilaments past each other

142
Q

actin extensions

A
  • pseudopodia
    -filopodia
    -lamellipodia
143
Q

cytoplasmic streaming

A

acitive (needs energy) movement of cytoplasm to deliver things to parts of the cell

144
Q

prokaryotic cell division

A

fission

145
Q

why is prokaryotic cell division so much simpler than eukaryotic

A

dna in 1 circular chromosome in prokaryotic but in eukaryotic it is in multiple linear chromosomes

146
Q

fission mechanism

A

-replicate cytoplasm
-replicate dna
-each copy of dna attach to one side of membrane -> seperate through cell elongation

147
Q

number of eukaryotic chromosomes

A

set number per species
*humans: 46 per somatic cell (not sex cell)

148
Q

mitotic spindle

A

microtubules used in mitosis to separate sister chromatids to either side of the cell; separate chromosomes for daughter cells

149
Q

what do microtubules do

A

arrange and move chromosomes

150
Q

where do microtubules attach to chromosomes

A

kinetochore; specialized point of centromere

151
Q

what do non kinetochore microtubules do

A

build cage

152
Q

spindle poles (of the microtubules cage)

A

centriole pairs

153
Q

spindle pole organization

A

centriole pair w/ centrosome; chromatids attached to single chromosome at centromed

154
Q

kinetochore

A

proteins surrounding centromere

155
Q

how does spindle move chromatids (2)

A

1) shortening; microtubules disassemble at kinetochores
2)sliding along microtubules using motor proteins

156
Q

Interphase (G1, S, G2)

A

cells grows and replicates dna to prepare for cell division

157
Q

Prophase

A

-winding up of dna into chromosomes

158
Q

Prometaphase

A

nuclear envelope breaks down (stored to be reformed later); spindle starts to form

159
Q

Metaphase

A

chromosomes attach to spindle fibers and line up in center

160
Q

Anaphase

A

spindle pulls sister chromatids to either end of the cell

161
Q

Telophase

A

separates duplicated genetic material

162
Q

cytokinesis

A

subdivision of cytoplasm into 2 cells

163
Q

animal cell cytokinesis

A

cleavage furrow; pinches cell in middle -> 2 cells

164
Q

plant cell cytokinesis

A

cell plate; form new membrane from vesicles fusing in middle of cell

*cannot do cleavage because of rigid cell wall and turgor pressure

165
Q

cell cycle

A

life cycle of cells; G1, S phase, G2, M phase

166
Q

cell cycle checkpoints

A

protein complexes throughout the cell cycle that monitor activity/ make sure everything is going right

167
Q

G1 checkpoint

A

make sure cell large enough/ with enough neutrance; decide whether or not to divide

168
Q

G2 checkpoint

A

check if all of the DNA replicated correctly

169
Q

M checkpoint

A

check that all chromosomes are attached to spindle microtubules

170
Q

MPF

A

complex of 2 proteins that drives cell through G2 checkpoint

171
Q

how are checkpoints regulated

A

by “clock” protein cyclin; protein synthesised at a steady pace with specific thresholds
*disappears after mitosis; restarts clock

172
Q

cyclin dependant kinase (CDK)

A

protein that cyclin binds to and activates tp create active MPF

173
Q

why do cells reproduce to make non genetically identical offspring

A

genetic variation can make a species more resistant and have better chances of survival

174
Q

prokaryote reproduction -> genetically varied offspring

A

1) transformation: specialized channels take up DNA from outside -> incorporated into prokaryote chromosome
2) conjugation: bits of dna transfer between prokaryotes

175
Q

how do prokaryotes transfer bit of dna between each other

A

pili

176
Q

how do eukaryotes produce genetically varied offspring

A

cell fusion during fertilization

177
Q

diploid

A

pairs of homologous chromosomes (4 chromatids)

178
Q

ex of diploid cell

A

somatic cell

179
Q

haploid

A

only 1 homologue (2 sister chromatids)

180
Q

ex of haploid cell

A

sperm and egg cells (gametes)

181
Q

homologous chromosome

A

2 chromatids joined by centromere with same genes in same regions BUT different versions of the gene/ different alleles

182
Q

alleles

A

one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome

183
Q

meiosis

A

diploid cell -> 4 haploid cells

184
Q

meiosis 1

A

meiotic spindle lines up homologous chromosomes next to each other -> separate homologous chromosomes
*sister chromatids stay together!

185
Q

what do chromosome synapses do

A

pair sister chromatids together
*prophase

186
Q

tetrad/ bivalent

A

4 sister chromatids/ 2 chromosomes together; recognize similar dna/ nucleotide sequences -> join together
*metaphase

187
Q

crossing over

A

dna from 1 homologue breaks and joins with other chromosome -> non parental chromosomes (mixes genes from both chromosomes)

188
Q

meiosis 2

A

sister chromatids separate -> 4 haploid cells
*no dna replication before

189
Q

mendel 1865 experiment

A

breeding pea plants and observing inheritance of traits (flower color, seed color, seed shape)

190
Q

true breeding parents

A

offspring keep traits unless you allow/ breed for cross fertilization

191
Q

alleles

A

different versions of the same gene
*homologous chromosomes with certain gene in the same region -> different alleles

192
Q

mendel’s law of segregation

A

the 2 alleles in the parent segregate from each other during formation of gametes; equal probability of passing on either allele

193
Q

homozygotic

A

2 of the same allele (recessive or dominant)

194
Q

heterozygotic

A

2 different alleles

195
Q

mendel’s law of independent assortment

A

the way 1 set of alleles separate from each other into gametes has no impact on the separation of another set of alleles
*if genes on different chromosomes

196
Q

phenotype

A

physical traits individual has

197
Q

genotype

A

genetic information individual has passed on from parents

198
Q

how to determine genotype; homozygous dominant vs heterozygous dominant

A

test cross; breed with homozygous recessive

199
Q

dihybrid cross

A

cross 2 heterozygous genes on different non homologous chromosomes (independent assortment)nat the same time

200
Q

dihybrid cross genotype ration

A

9:3:3:1

201
Q

what does independent assortment increase

A

genetic variation

202
Q

how to see all of the genetic possibilities

A

punnett square

203
Q

diagram to see what genotype is dominant

A

pedigree

204
Q

incomplete dominance

A

heterozygote has phenotype that is intermediate/ in between homozygotes
ex. white + red -> pink

205
Q

co dominance

A

different alleles give qualitatively different dominate traits -> see both traits
ex. blood type (A and B carbohydrates)

206
Q

transfusion reaction

A

immune response to unfamiliar blood type cells

207
Q

O blood type

A

no carbohydrates on blood cells

208
Q

universal blood receiver

A

AB

209
Q

universal blood donor

A

O

210
Q

several mutant alleles of the same gene

A

can inhibit, increase or completely change protien function

211
Q

several mutant alleles of the same gene nomenclature

A

gene name ^ xxx (superscript)

212
Q

pleiotropy

A

single mutant allele affects many tissues and processes
ex. beta globin gene mutation causes blindness, liver failure and heart attacks

213
Q

specialization

A

organs for production of nutrient filled egg (ovary) or mobile sperm (testes)

214
Q

hermaphrodites

A

have both reproductive organs; can vary over time or exist at the same time

215
Q

autosomes

A

non sex chromosomes
humans: 22 pairs

216
Q

sex chromosomes

A

make genetic choice between making sperm or egg
- XX makes ovaries -> egg
- XY makes testes -> sperm

217
Q

SRY gene

A

gene on Y chromosomes that encodes transcription factor that directs development of testes and hormone testosterone

218
Q

sex linked genes

A

XY is hemizygous for X- linked gene allele and Y- linked gene allele

219
Q

hemizygotic

A

individual who has only one member of a chromosome pair or chromosome segment rather than the usual two

220
Q

X- linked gene

A

gene on X chromosome

221
Q

Y- linked gene

A

gene on y chromosomes

222
Q

why are males more likely to inherit recessive X linked genes

A

dependent on only 1X allele because only have 1 X chromosome

223
Q

x linked mutations

A

more likely to be passed onto males because there are only genes expressed on the one X chromosome

224
Q

sex influenced traits

A

autosomal mutation influenced by sex physiological factors (ex. sex hormones)
*not on sex chromosome

225
Q

pedigree symbols

A

circle: XX
square: XY
shades indicate the phenotype

226
Q

x linked recessive trait passing on

A

male: only mother must have trait on 1 X chromosome
female: both parents must possess trait on X chromosome

227
Q

y linked trait

A

all XY offspring of XY with the trait will also inherit the trait

228
Q

how are X Y chromosomes paired during meiosis

A

pairing must be between similar segments of DNA; 40 shared genes between X and Y on tip of chromosome

229
Q

what is the region of similar DNA used to pair X and Y chromosomes called

A

pseudo- autosomal

230
Q

dosage compensation

A

XX have double the X linked genes as XY which produces 2x as much mRNA (BAD)

231
Q

dosage compensation; mammals

A

random inactivation of 1 X chromsome in XX individuals

232
Q

what are the inactive X chromosomes called (used for dosage compensation)

A

barr bodies

233
Q

how are barr bodies made

A

histones wrap chromosome so tightly it silences transcription so cannot make mRNA

234
Q

epigenetic mosaic

A

different mix in gene expression; heterozygous XX expresses both genes

235
Q

nondisjunction

A

chromosome separation fails during meiosis (either stage) and produces unequal gametes

236
Q

gametes produced by nondisjunction

A

aneuploidies

237
Q

trisomy

A

3 of one chromosome; leads to birth defects (only 3 survivable ones)

238
Q

momsomy

A

only 1 of one chromosome; not survivable to birth on autosomal chromosomes

239
Q

trisomy ex

A

down syndrome; trisomy on chromosome 21

240
Q

nondisjunction in sex chromosomes

A

XXY
XXX
X
* ONLY SURVIVABLE HUMAN MONOSOMY
XYY

241
Q

XXY

A

1 barr body; reduced testes, testosterone and fertility

242
Q

XXX

A

2 barr bodies

243
Q

X

A

no barr bodies; only survivable human monosomy

244
Q

XYY

A

both Y active; extra fertile testes and could lead to more severe defects

245
Q

fruit fly gene nomenclature

A

x+ = dominant/ normal
x or x- = mutant
named after the mutant form

246
Q

recombinant

A

non parental chromosome; crossing over has occurred

247
Q

crossing over

A

parts og homologous chromosomes in meiosis 1 cross and make tetrad; chromosome recombine at chiasm and forms non parental chromosome

*more genetic variability is added

248
Q

tetrad

A

4 connected chromatids; the point where homologous chromosomes exchange genetic material by the process of crossing over

249
Q

independent assortment test cross

A

equal amount of all 4 gametes

250
Q

where on gene must crossing over occur for genes linked on the same chromosome

A

in between the 2 genes of interest
*happens more commonly when genes further apart

251
Q

unit for mapping matants

A

centimorgans/ map units= % of offspring with non parental geneotype

252
Q

50 map units

A

50/50 chance of recombinant or parental chromosomes
- less than 50 = recombinant
- greater than 50 = parental

253
Q

polygenic trait

A

one phenotype caused by more than 1 gene; mutation in all genes causes phenotype

254
Q

what does polygenic inheritance lead to

A

quantitative variation in interiable quantitative trait

255
Q

epistasis

A

complex interactions between genes and traits

256
Q

when one gene turns the entire pathway off, how is that gene described

A

that gene is epistatic to the other genes in the polygenic inheritance

257
Q

how to determine genetic vs. environmental influence

A

twin tests; monozygotic (identical) vs. dizygotic (fraternal)

258
Q

concordance

A

the probability that both twins have a certain phenotype given that one has the characteristic

259
Q

cadherin

A

cell adhesion molecule

260
Q

mitochondrial gene inheritance

A

male and female offspring of an affected XX parent show the trait; mother to child

*XY parents never transmit the trait to their offspring

261
Q

what does the signalling cell produce

A

signaling molecule known as the receptor

262
Q

what do ligands produce

A

signaling cell (which the signalling molecule binds to)

263
Q

kinase function

A

type of protein adds a phosphate group to another protein

264
Q

inheritance by non nuclear chromosomes

A

genetic inheritance from dna from semi autonomous organelles (chloroplasts and mitochondria)

265
Q

does non dna information pass down through fertalization; epigenetics/ gene expression

A

as of now we don’t think so; dna methylation and gene expression lost after fertilization

266
Q

protist

A

single celled

267
Q

colony

A

collection of individual cells

268
Q

multicellularity

A

collection of eukaryotes that has a more complex organizational structure than colonies; interconnectedness and communication.

269
Q

how does a multicellular organism forms

A

single cells goes through division -> leads to differentiation of cells (specialization)

270
Q

cell signaling

A

coordination between cells in multicellular organisms

271
Q

fungi cell signaling

A

cytoplasmic connections; breaks in cell wall so cytoplasms are directly connected and anything can go through (proteins, organelles, etc)

272
Q

syncytial arrangment

A

cells fused together so things can fow between them; direct cytoplasm connections

273
Q

animal cell signaling

A

gap junctions; small pores that can pass small molecules between cells (ions, monomers, cAMP)

274
Q

plant cell signaling

A

plasmodesmata; large pores used to pass large molecules between cells (proteins, mRNA, etc)

275
Q

extracellular signaling

A

cell communication outside of the cell via signaling molecules

276
Q

ligands

A

a signaling molecule that binds to receptor protein -> trigger response in cell

277
Q

signal transduction pathway

A

The chains of molecules that relay intracellular signals

278
Q

ligand example; steroids

A

-easily diffuses across membrane (not normally the case)
-binds and activates receptor proteins
-receptor- steroid complex becomes active transcription factor
- binds to specific enhancer dna
- stimulates transcription

279
Q

factors in information flow (4)

A

1) specificity of signal/receptor pathway
2) scale of impact (part or whole cell)
3) feedback (pos or neg)
4) amplification caused?

280
Q

amplification

A

enzymes in pathway receive and amplify protein at every step; pos feedback

281
Q

what receptors exhibit amplification

A
  • transcription factors
  • protein kinase
  • cyclases
  • G proteins
  • secondary messengers
282
Q

secondary messengers

A

non protein messengers; cAMP, Ca2+, ions, lipids, gasses. etc

283
Q

G proteins

A

family of proteins that act as molecular switches inside cells

284
Q

G protein coupled receptors

A

activates G proteins by breaking bond with GDP and binding protein with GTP

285
Q

inactive g protein

A

bound to GDP

286
Q

active g protein

A

bound to GTP

287
Q

ex of g protein activation

A

adrenaline; activates alpha G protein -> activates adenylyl cyclases -> makes cAMP -> activates protein kinase A -> increases heart rate

Bio 151 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions