Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Molecular Biology > DNA, Chromosomes, and Genomes 1 (lecture 1) > Flashcards

DNA, Chromosomes, and Genomes 1 (lecture 1) Flashcards

1
Q

The information-containing elements that determine the characteristics of a species

A

Genes

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

Genes are passed form cell to daughter cell mostly

A

unchanged

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

Genes undergo accurate and ____ replication

A

unlimited

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

The discovery that hereditary information is carried on chromosomes was made in the late

A

19th century

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

Chromosomes are visible by light microscopy when the cell

A

divides

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

Chromosomes contain ____ and ____ in equal amounts

A

DNA and protein

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

What are the building blocks of DNA

A

Nucleic Acids

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

Polynucleotides have a polarity: ____ phosphoryl end ____ hydroxyl end

A

5’ phosphoric end and 3’ hydroxyl end

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

nucleotides are a 5-carbon sugar and nitrogenous base covalently linked via

A

glycosidic bond

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

what are the nitrogenous bases in DNA

A
  • Adenine
  • Cytosine
  • Guanine
  • Thymine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DNA has 1 turn every ___ base pairs

A

10 base pairs

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

DNA consists of ___ long polynucleotide chains with ____ types of nucleotide subunits

A

2, 4

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

Purines

A

Adenine

Guanine

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

Pyrimidines

A

Cytosine

Thymine

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

Adenine pairs with thymine with ___ hydrogen bonds

A

2

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

Guanine pairs with cytosine with ____ hydrogen bonds

A

3

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

DNA serves as it’s own

A

template

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

DNA is enclosed in the

A

Nucleus

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

Eukaryotic DNA is packaged into

A

chromosomes

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

The human genome is _____ nucleotides distributed over ___ different chromosomes

A

3.2 x 10^9, 24

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

each chromosome is single long _____ DNA molecular associated with proteins that fold and pack it into compact structure

A

Linear

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

Packaging of DNA into a chromosome is similar to packing 24 miles of thread into a

A

tennis ball

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

DNA + protein =

A

chromatin

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

each human cell contain 2 copies of each chromosome (maternal and paternal homologs) except for ___ and ____

A

germ cells and RBCs

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

humans have ____ pair of autosomes and ___ sex chromosomes

A

22, 2 (46 total chromosomes)

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

Banding pattern of chromosomes can be seen with _____ stain under light microscopy

A

Giemsa stain

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

The used of a Giemsa stain to show banding pattern of chromosomes is used to

A

identify and number chromosomes

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

Banding pattern seen with Giemsa stain under high microscopy is still used in

A

cytogenetics laboratories for karyotype analysis

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

Cytosine techniques are very helpful in recognizing

A

chromosomal translocations

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

Chromosomal translocations can occur during an

A

abnormal recombination event

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

Balanced translocations maintain

A

the correct amount of genetic material

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

Translocations frequently occur in

A

cancer cells

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

Translocation of chromosomes 9 and 22 form the ______ chromosome on Chromosome 22, commonly found in chronic myelogenous leukemia (BCR-ABL fusion gene)

A

Philadelphia chromosome

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

Translocation of chromosomes ___ and ___ form the Philadelphia chromosome on Ch 22, commonly found in chronic myelogenous leukemia (BCR-ABL fusion gene)

A

9 and 22

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

What information is found on chromosomes

A
  • Genes
    • Encoding proteins
    • Encoding RNA molecules
  • Interspersed DNA that does not contain genes
    • Regualtory information
    • “junk” DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

exon

A

Translated portion of gene

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

Intron

A

non-coding portion of gene

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

First draft of the Human genome project was in ____ and finished sequence published in ____

A

2001, 2004

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

Large average gene size, with only ____% of the gene comprising coding region (mostly intronic sequence)

40
Q

Percentage of DNA sequence in exons (protein-coding sequences)

41
Q

Percentage of DNA in other highly conserved sequences

42
Q

Percentage of DNA in high-copy-number repetitive elements

A

approximately 50%

43
Q

DNA length

A

3.2 x 10^9 nucleotide pairs

44
Q

Number of genes coding for proteins

A

approximately 21,000

45
Q

Largest gene coding for protein

A

2.4 x 10^6 nucleotide pairs

46
Q

Mean size for protein-coding genes

A

27,000 nucleotide pairs

47
Q

smallest number of exons per gene

48
Q

Larges number of exons per gene

49
Q

Mean number of exons per gene

50
Q

Largest exon per size

A

17,106 nucleotide pairs

51
Q

Mean exon size

A

145 nucleotide pairs

52
Q

number of noncoding RNA genes

A

Approximately 9000

53
Q

Number of pseudogenes

A

more than 20,000

54
Q

What is a pseudogene

A

a DNA sequence closely resembling that of a functional gene, but containing numerous mutations that prevent its proper expression or function

55
Q

during _____ chromosomes are replicated, they are decondensed and can’t be easily distinguished

A

interphase

56
Q

During ____ chromosomes become highly condensed and separated into two daughter nuclei

57
Q

what are the requirements for a copy to be passed on to each daughter cell at division

A
  • Requires replication
  • Separation of copies
  • Partitioning to daughter cells
58
Q

Where duplication of the DNA begins

A

DNA replication origin

59
Q

Allows one copy of each duplicated and condensed chromosome to be pulled into each daughter cell when the cell divides.

A

Centromere

60
Q

The ______ protein complex attaches to the centromere

A

Kinetochore

61
Q

At the ends of a chromosome, contain repetitive sequences that enable the ends to be efficiently replicated

62
Q

Mitotic chromosomes are condensed _____ times compared to interphase DNA

63
Q

_____ situation: must allow rapid localized access to DNA for gene expression

64
Q

DNA binding proteins involved in forming chromosomes include ____ and ______ chromosomal protiens

A

histones and non-histone

65
Q

Protein + nuclear DNA =

66
Q

_____ is the most basic unit of chromosome packing is the nucleosome

A

Nucleosome

67
Q

if chromosome is partially unfolded it forms

A

beads on a string (string= DNA, beads= DNA wound around histones)

68
Q

Chromatin isolated directly from interphase nucleus forms ____nm thick thread

69
Q

Digestion with nucleases break down DNA by cutting between _____ and degrading the exposed DNA between ______

A

between nucleosomes and degrading the exposed DNA between nucleosome core particles (linker DNA)

70
Q

Each individual nucleosome core particle consists of ____ histone proteins. ___ Molecules each of ____, ______, _____, _____ and ____ stranded DNA that is ______ nucleotide pairs long

A

8 (histone octamer)

  • 2 molecules of each H2A, H2B, H3, H4
  • 2x stranded DNA that is 147 nucleotide pairs long
71
Q

Linker DNA can be ____ to ____ nucleotides

A

few to 80 nucleotides

72
Q

Nucleosomes repeat every ____ nucleotide pairs or so

73
Q

Histones are small proteins with common structural motif called

A

histone fold

74
Q

high resolution structure of nucleosome core particle is disc-shaped with DNA wrapped _____ turns

75
Q

Nucleosomes have an _________ that extends out form the core and are subject to covalent modifications important for chromatin regulation

A

N terminal amino acid tail

76
Q

_____ hydrogen bonds are formed between DNA and the histone core in each nucleosome

77
Q

How is DNA packaged

A
  • 142 hydrogen bonds are formed between DNA and the histone core in each nucleosome
  • Hydrophobic interactions
  • Salt linkages
    • lysine and arginine (positive charges) comprise more than 1/5 of histone residues; effectively neutralize negative charged DNA backbone
78
Q

____ and _____ Comprise more than 1/5 of histone residues; effectively neutralize negatively charged DNA backbone

A

Lysine and Arginine

79
Q

Histones are _____ conserved meaning most changes would be

A

highly conserved meaning most changes would be lethal

80
Q

Only __ histone differences between pea and cow H4

81
Q

Specialized _______ add to various possible chromatin structures

A

variant histone proteins

82
Q

Nucleosomes are in a constant state of

83
Q

DNA is unwrapped in the nucleosome ____ times per second, and remains unwrapped for ______ milliseconds before tightening up again

A
  • 4 times per second

- 10-50 milliseconds

84
Q

Chromatin remodeling complexes allow further loosening of _____

A

DNA/Histone contact

85
Q

Proteins are related to helicases and are ____ dependent; bind to both protein core and DNA

86
Q

Repeated cycles catalyzes nucleosome sliding, making DNA available to other

A

proteins in the cell

87
Q

Nucleosome packing forms a dense fibrous structure with diameter of

88
Q

Nucleosome packing maybe by ____ model, stacking may be facilitated by histone tails (esp ____)

A

zig-zag, H4

89
Q

Histone ____ “linker histone” is present in 1:1 ratio with nucleosome cores

90
Q

Histone tails are largely _____, suggesting that they are highly flexible

A

unstructured

91
Q

Histone trials can form interactions with

A

adjacent nucleosomes

92
Q

What is the largest histone protein

93
Q

Linker histone

94
Q

Is H1 well conserved

95
Q

H1 (linker histone) contacts both ___ and ___

A

DNA and protein

96
Q

H1 (linker histone) changes the path of the DNA as it exits the

A

nucleosome

Molecular Biology (14 decks)

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