Molecular Diagnostics Nucleic Acid & Chromosome Structure Flashcards
(93 cards)
1
Q
What does DNA stand for?
A
Deoxyribonucleic Acid
2
Q
What is the purpose of DNA?
A
Stores genetic information
3
Q
Where the majority of DNA is found
A
Nucleus
4
Q
Where a small amount of DNA can be found
A
Mitochondria
5
Q
Anti-parallel double-stranded helix that looks similar to a twisted ladder
A
DNA
6
Q
What does RNA stand for?
A
Ribonucleic Acid
7
Q
Purpose of RNA
A
Translates DNA sequence into proteins
8
Q
Where most RNA is found
A
Cytoplasm
9
Q
Where some RNA may be found
A
Nucleus
10
Q
-Single-stranded
-Contains uracil instead of thymine
A
RNA
11
Q
Building blocks of DNA and RNA include what 3 things?
A
-Nitrogenous bases
-Sugars
-Phosphate group
12
Q
Biggest difference between purines and pyrimidines
A
Purines have a 2 ring structure
13
Q
How many (and which) nitrogenous bases are purines?
A
2:
-Adenine
-Guanine
14
Q
How many (and which) nitrogenous bases are pyrimidines?
A
3:
-Thymine
-Uracil
-Cytosine
15
Q
DNA’s sugar
A
Deoxyribose
16
Q
RNA’s sugar
A
Ribose
17
Q
Difference between deoxyribose and ribose sugars
A
Deoxyribose has lost an oxygen
18
Q
What does a phosphate group consist of?
A
A phosphorus atom surrounded by oxygen atoms
19
Q
Sugar + Nitrogenous Base = ?
A
Nucleoside
20
Q
What makes up a nucleoside?
A
Sugar + Nitrogenous Base
21
Q
Nucleoside + Phosphate group = ?
A
Nucleotide
22
Q
What makes up a nucleotide?
A
Nucleoside + Phosphate group
23
Q
What is a chain of nucleotides called?
A
Nucleotide polymer
24
Q
What are the ends of DNA called?
A
3’ and 5’
(Three prime and five prime)
25
The 5' end of DNA has a free ___________
Free phosphate group
26
The 3' end of DNA has a free __________
Free pentose sugar
27
TRUE or FALSE
Nitrogenous bases always pair purine with pyrimidine
TRUE
28
Adenine will always pair with which pyrimidine(s)
Uracil (RNA)
&
Thymine (DNA)
29
Cytosine will always pair with which purine?
Guanine
30
Thymine will always pair with which purine?
Adenine
31
Uracil will always pair with which purine?
Adenine
32
Guanine will always pair with which pyrimidine?
Cytosine
33
How many hydrogen bonds form between adenine and thymine?
2 hydrogen bonds
34
How many Hydrogen bonds form between adenine and thymine?
2 Hydrogen bonds
35
How many Hydrogen bonds form between adenine and thymine?
2 Hydrogen bonds
36
How many Hydrogen bonds form between guanine and cytosine?
3 Hydrogen bonds
37
For DNA, what is meant by anti-parallel?
5' of one strand binds to the 3' of another
38
DNA is always read or recorded _____ to _____
5' to 3'
39
What is the reason for DNA being twisted?
The nitrogenous bases are hydrophobic and the sugar-phosphate backbone is hydrophilic; so the backbone will protect the bases from water in the cell.
40
Enzymes and protein involved in DNA replication (7)
-Helicase
-Single-Stranded Binding proteins
-Topoisomerase
-Primase
-DNA Polymerase III
-DNA Polymerase I
-Ligase
41
DNA Replication:
Unzips the DNA strands
Helicase
42
DNA Replication:
Attaches to the unzipped strands of DNA to keep them from binding back to each other
Single-Stranded Binding proteins
43
DNA Replication:
Works to keep the DNA strands from supercoiling
Topoisomerase
44
DNA Replication:
Creates RNA primers required to start replication
Primase
45
DNA Replication:
Signal DNA polymerase III where to start building the new strand of DNA
RNA primers
46
DNA Replication:
Starts building the new DNA strand
DNA Polymerase III
47
DNA Replication:
removes RNA primers when it is time.
DNA Polymerase I
48
DNA Replication:
Responsible for "gluing" Okazaki fragments together on the lagging strand
DNA Ligase
49
DNA replication is considered _______________, meaning the result is 2 double-stranded DNAs; each of which have one "parent" strand and one "daughter" strand.
Semi-conservative
50
The "Y" shaped structure where new DNA strands are synthesized
Replication fork
51
The DNA strand that can be built continuously is known as the __________.
Leading strand
52
The DNA strand that can't be built continuously is known as the ______________
Lagging strand
53
The lagging strand builds in fragments known as ___________
Okazaki fragments
54
What degrades DNA?
Nucleases aka DNAses
55
What are the 2 types of nucleases?
-Exonucleases
-Endonucleases
56
Nuclease that nibble in from the end of the DNA strand
Exonuclease
57
Nuclease that will start degrading the DNA strand from somewhere in the middle
Endonuclease
58
Enzymes that attack specific sequences of DNA
Restriction enzymes
aka
Restriction endonucleases
59
What is a nickname for restriction enzymes?
Molecular scissors
60
What produces restriction enzymes and why?
Bacteria to protect against bateriophages
61
Which restriction enzymes makes random cuts?
Type I
62
Which restriction enzyme makes non-specific cuts?
Type III
63
Which restriction enzyme makes specific cuts?
Type II
64
Which restriction enzyme is most useful for molecular techniques?
Type II
65
What is the termed used to describe the overhang/free flappy section of a DNA strand after a restriction enzyme cuts it?
Sticky end
66
What is the term used to describe a cut DNA strand that has no overhang/free flappy end?
Blunt end
67
Definition:
All of the genes in an organism
Genome
68
Definition:
An order or sequence of nucleotides on a chromosome that contain all the genetic information to make a functional protein or RNA product
Gene
69
Definition:
Different versions of the same sequence, gene, or locus
Allele
70
Definition:
Genetic DNA composition of an organism
Genotype
71
Definition:
Physical appearance of an organism
Phenotype
72
Definition:
Defined site or location of a gene on a chromosome
Locus
73
Function of RNA
Translate DNA code into proteins
74
Where is RNA typically found?
Cytoplasm
75
RNA that is found in the nucleus is in what form?
mRNA (messenger)
76
How is RNA made?
Transcribed from DNA
77
What is the pentose sugar for RNA?
Ribose
78
What nitrogenous base is different in RNA when compared to DNA?
Uracil instead of Thymine
79
TRUE or FALSE:
RNA is more stable than DNA
False
80
What are the 3 types of RNA?
-mRNA (messenger)
-rRNA (ribosomal)
-tRNA (transfer)
81
Which type of RNA carries information from DNA to the ribosomes?
mRNA
82
Which type of RNA makes up part of the machinery used to make the proteins?
rRNA
83
Which type of RNA is responsible for carrying individual amino acids to the ribosome where they are joined by peptide bonds to make a protein?
tRNA
84
TRUE or FALSE:
You can always see chromosomes
False - only during cell division
85
How does DNA normally exist in the nucleus?
As chromatin
86
What does DNA wrap itself around to form chromosomes?
Histones
87
What is known as "Beads on a string" or when DNA is wrapped around histones?
Nucleosome
88
What are histones?
proteins
89
What do nucleosomes coil up to form?
Chromatin
90
Terminology:
-Individual's collection of chromosomes
-Lab technique for imaging chromosomes
-Allows us to look for abnormalities
Karyotype
91
A nucleosome is formed between DNA and how many histone proteins subunits?
8
92
What is the length of DNA in the nucleus of each cell?
6 feet
93
Enzyme that joins DNA fragments together by reforming the sugar-phosphate bonds of DNA
Ligase
