Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Genetics 380 > Nucleic Acids Chromatin And Chromosomes > Flashcards

Nucleic Acids Chromatin And Chromosomes Flashcards

(63 cards)

Start Studying
1
Q

types of DNA

A

(1) chromosomal DNA in nucleus (2) mitochondrial DNA (3) chloroplast DNA (4) bacterial DNA (chromosomes and plasmids) (5) viral DNA

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

messenger RNA

A

translated into polypeptides

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

ribosomal RNA

A

integral part of ribosome

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

transfer RNA

A

carry amino acids in for polypeptide synthesis

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

small nuclear RNAs

A

help process pre mRNAs into mRNAs; help process and assemble ribosomal RNAs

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

ribozymes

A

function like enzyme proteins (ex: cleave RNAs, assemble polymer, rRNA)

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

antisense RNAs

A

interfere w protein production ex: microRNAs (miRNA), small interfering RNAs (siRNAs); some enable protein production

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

piwi interacting RNAs

A

antisense RNA; suppress transcription of transposons in testes, interact with the piwi protein

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

CRISPR RNAs

A

help bacteria and archaea destroy invading viruses and plasmids; antisense RNA

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

long noncoding RNAs

A

some act as molecular decoys and bind up proteins that would otherwise destabilize chromosomes; others cause change in structure of chromosomes, inhibiting gene expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

molecule of inheritance must

A

contain info that determines all traits and functions of the organism; be stable in general but also have ability to change in some ways w/o causing harm to organism; be carried on chromosomes

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

chromosomal theory of inheritance (Sutton 1902)

A

organisms possessed matched pairs of maternal and paternal chromosomes that separated from each other during meiosis and constitute the physical basis of Mendelian law of heredity

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

Griffith

A

one bacterium can transmit its characteristics to another; mice infected with S strain always died even mix of R strain and heat killed S strain

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

Avery, MacLeod, McCarty (1944)

A

DNA, not RNA or protein, was transforming principle; transforming principle was heritable

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

Hershey and Chase (1952)

A

showed that bacteriophage injects its DNA, not protein, into its target bacteria; 2 sets of E. Coli: protein vs. nucleotide

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

double helix

A

Franklin and Wilkins showed DNA is helical and made of 2 parallel parts; helix contains 10 nucleotides per turn and has diameter of 20 angstroms

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

Chargaff’s rule

A

of A bases = T bases and C bases = G bases

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

Watson and Crick (1953)

A

two DNA strands lie in antiparallel arrangement; bonds between A-T bases and C-G bases hold the two strands of double helix together; concept of complementary bases immediately suggested a mechanism for DNA rep.

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

nucleoside

A

sugar + nitrogenous base

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

nucleotide

A

nucleoside + phosphate group

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

sugar

A

ribose (RNA) or deoxyribose (DNA)

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

DNA contains

A

ACGT

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

RNA contains

A

ACGU (single stranded)

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

Why RNA has uracil and DNA has thymine

A

uracil is E less expensive to produce than thymine = E saving; cytosine is easily converted to uracil (does not require enzyme) deamination replaces the NH2 amine group on cytosine w a c=o (carbonyl) group; over time many C to U changes cause problems w DNA not RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
C to U mutations
disease causing mutation in DNA (template for replication for several generations of cell cycles); RNAs are short lived so there isn't enough time for C to U to occur and disturb RNA function
26
5' and 3' ends on nucleic acid
new nucleotide is added by hooking the phosphate group on the 5' carbon of the new nucleotide onto the O that is on the 3' carbon of the previous nucleotide; 5' phosphate at "front" end; OH on the "tail" end
27
double helix structure
sugar phosphate backbone of each strand on outside of helix; covalent bonds between sugar and phosphate hold nucleotides together in a single chain; bases stacked inside; H bonding (non covalent) between complementary bases keeps 2 DNA strands together; major and minor grooves formed; important for protein building
28
B form DNA configuration
typical configuration in vivo proposed by Watson and Crick, right handed helix
29
A form DNA configuration
under high salt concentrations helix gets a little more compact, still right handed helix
30
RNA structure
single stranded but can fold on itself and adopt a number of conformation; 2 stretches of bases w complementary sequences they will bind to each other (does not have to be a perfect complementary); stem and loop hairpins; right handed double helices; internal loops and bulges
31
transfer RNA structure (tRNA)
contain modified nucleotides (ex: methylguanosine); characterized by anticodon which binds mRNA at ribosome and amino acid-carrying portion
32
not all genomes contain double stranded DNA
viruses w 2x stranded DNA genomes others w 2x stranded RNA genomes, 1x DNA genomes, 1x RNA genomes
33
mitochondrial and chloroplast DNA
circular; encode rRNAs, tRNAs and proteins that are essential for function of mitochondrion; over evolution genes transferred from mitochondrion to nucleus and from chloroplasts to mitochondria
34
dinucleotide
2 nucleotides
35
trinucleotide
three nucleotides
36
oligonucleotide
less than 40
37
denaturing
separating 2 DNA strands often using heat to break the H bonds between bases (often called melting strands); seq. w high G-C content has higher melting temp than one w high A-T content
38
annealing
complementary single strands of DNA H bond back together
39
bacterial (chromosomal) DNA is attached
to proteins; instead of nucleus there is nucleoid region; DNA forms loop domains each anchored by DNA binding proteins; DNA in each loop is supercoiled
40
bacterial DNA is supercoiled
topoisomerases catalyze changes in chromatin configuration + negatively supercoil DNA and nucleoid associated proteins (NAPs) hold it in the proper configuration; can be positively or neg supercoiled
41
plasmid
small, circular piece of DNA that replicates independently from bacterium itself; can be replicated and copies transferred to another bacterium by process known as conjugation; don't contain genes essential for life but may contain genes that encode protein that help them survive and propagate (ex: resistant factors that protect again antibiotics, fertility factors that enable them to engage in conjugation w other bacteria more effectively)
42
bacterial conjugation
plasmids are copied and transferred
43
toposiomerases
temporarily cut the DNA strands and rotate the ends of the DNA so it can coil
44
nucleosome
DNA is wound around 8 histone proteins to make nucleosome; eu DNA is wound around histone proteins
45
histone 1 protein
locks DNA around histones; nucleosome plus H1 = chromatosome
46
linker DNA
connects chromatosomes
47
scaffold proteins
help hold the coils together
48
chromatin
combination of DNA and proteins
49
acetylation of lysines in histone proteins
allows histones to loosen so DNA or gene can replicate to make its mRNA; DNA has neg. charge lysines in histone proteins have pos. charges; neg. charged acetyl group on lysine causes histones to release DNA a little and allows it to open so protein needed for trans. or rep. can access DNA
50
histone acetyltransferase
puts acetyl groups on the histone proteins (histone deacetylase takes them off)
51
coiling DNA
aligns reg. sequences bc they may lie far from the promoter
52
chromatin relaxes to allow gene expression
histones must loosen grip on DNA in order for gene to make its mRNA
53
linear chromosomes
eukaryotic; metacentric, submetacentric, acrocentric, telocentric
54
polycentric chromosomes
eukaryotes have chromosomes w centromeres distributed along the chromosome; spindle fibers attach all along the chromosome
55
repeated seq. in centromere
different orgs. have diff specific centromeric sequences; centromeres contain variant form of histone H3 and adopt characteristic chr. configuration which allows them to serve their functions
56
kinetochore
specialized protein structure around centromere
57
spindle fibers
grab chromosomes' centromeres; bind w kinetochores and pull apart homologous chromosome pair during anaphase I or meiosis and 2 sister chromatids get pulled apart during anaphase II of meiosis or anaphase of mitosis
58
anaphase
spindle fibers draw chromosomes apart
59
telomeres
must be stabilized; one strand project beyond other strand + protection of telomere protein binds to single stranded DNA
60
t-loop
telomeric end of long strand binds itself at a complementary seq.
61
shelterin
multi-protein complex that binds telomeres and keeps them from being replicated in most orgs.
62
euchromatin
less condensed (still supercoiled) and most genes located here are active
63
hetermochromatin
more condensed than euchromatin and genes are inactive; if chr. rearrangement moves gene too close to heterochr. region this may silence the gene

Genetics 380 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions