Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIOL 207 Lecture (Genetics: A conceptual Approach 6th/7th Ed) > Chapter 10.1-10.3 > Flashcards

Chapter 10.1-10.3 Flashcards

(68 cards)

Start Studying
1
Q

What were the four important characteristics of genetic material that biologists knew it had to contain even before nucleic acids were recognized?

A
  1. genetic material must contain complex information - must be capable of storing large amounts of info
  2. genetic material must replicate with precision and accuracy
  3. Genetic material (genotype) must encode phenotype
  4. Genetic material must be able to vary to allow differences in genetic makeup
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The genetic material must carry large amounts of info, replicate faithfully, express coding instructions as phenotypes and have the capacity to vary.

Why was the discovery of the structure of DNA so important for understanding genetics?

A

It was impossible to understand how genetic information was encoded or expressed without first knowing the structure of DNA

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

Who discovered a material that he named nuclein when he isolated the nuclei in the white blood cells of pus. What was it later renamed?

A

Johann Friedrich Miescher

Later renamed nucleic acid

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

Miescher’s nuclein must have consisted of _____ and ____

A

Miescher’s nuclein must have consisted of DNA and protein

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

In the late 1800’s, ______ carried out work on the chemistry of DNA and determined that it contains four nitrogenous bases

A

In the late 1800’s, Kossel (Albrecht) carried out work on the chemistry of DNA and determined that it contains four nitrogenous bases

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

Who discovered that DNA consists of large number of linked, repeating units called nucleotides?

A

Pheobus Aaron Levene

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

Levine came up with what (incorrect) hypothesis regarding nucleotides?

A

Tetranucleotide hypothesis: DNA consists of a series of four-nucleotide units each containing all four bases in a fixed sequence

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

Who disproved the tetranucleotide hypothesis?

A

Erwin Chargaff and his colleagues

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

What are “Chargaff’s Rules”

A

Rules developed by Erwin Chargaff concerning the ratios of bases in DNA

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

What contribution did Levene make to our understanding of DNA structure?

A

He determined that DNA consists of nucleotides

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

______ identified the basic rules of heredity in 1866

A

Mendel identified the basic rules of heredity in 1866

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

By the early 1900s biologists had concluded that genes resided on ______ which were known to contain both _____ and _____

A

By the early 1900s biologists had concluded that genes resided on chromosomes which were known to contain both DNA and protein

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

What two things provided pivotal evidence that DNA (not protein) was the genetic material?

A

Two sets of experiments, one on bacteria and the other on viruses

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

Who first observed the phenomenon of transformation?

A

Griffith, Fred

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

What is transformation?

A

Transformation occurs when bacteria take up DNA from the medium in which it is growing; ie incorporates foreign DNA into its own genome

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

What is the transforming principle (as named by Griffith after his experiment with mice)

A

Substance responsible for transformation. DNA is the transforming principle

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

Who (microbiologist) set out to understand the nature of Griffith’s transforming factor?

A

Avery, oswald

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

After 10 years of research, _____, ______, and ______ succeeded in isolating and partially purifying the transforming substance

A

After 10 years of research, Avery, Macleod, and McCarty succeeded in isolating and partially purifying the transforming substance

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

Avery, MacLeod and MacCarty showed that the transforming substance had a chemical composition closely matching that of _____ and quite different from that of _____

A

Avery, MacLeod and MacCarty showed that the transforming substance had a chemical composition closely matching that of DNA and quite different from that of Protein

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

Avery, MacLeod and McCarty showed that the transforming substance ______ at the same rate as purified DNA and that it absorbed ______ _____ at the same wavelength as DNA - thus providing compelling evidence that the transforming principle (and therefore genetic material) lies in the DNA

A

Avery, MacLeod and McCarty showed that the transforming substance precipitated at the same rate as purified DNA and that it absorbed Ultraviolet Light at the same wavelength as DNA - thus providing compelling evidence that the transforming principle (and therefore genetic material) lies in the DNA

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

If Avery, MacLeod and McCarty had found that samples of heat-killed bacteria treated with RNase and DNase transformed bacteria but that samples treated with protease did not, what conclusion would they have drawn?

(remember, in their experiment, the tube treated with DNase had no transformed type IIIS bacteria whereas the tubes treated with RNase and protease did)

A

Protein is the genetic material

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

The second piece of evidence that suggested DNA was the genetic material came from a study done by _____ and ______

A

The second piece of evidence that suggested DNA was the genetic material came from a study done by Hershey and Chase

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

What was the Hershey-Chase study?

A

Hershey and Chase worked with the T2 bacteriophage (virus) and showed that when a phage attaches to the outer wall of bacterial cell, it injects its DNA not its protein into the cell where it replicates and directs the cell to synthesize phage proteins.

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

Could Hershey and Chase have used a radioactive isotope of carbon instead of 32P? Why or why not?

A

No because carbon is found in both protein and nucleic acid

DNA contains phosphorus not sulfur;

Protein contains sulfur but not phosphorus

By injecting them with sulfur and phosphorus, they could identify which part of the phage (DNA or protein) was being transferred

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
The experiments on the nature of genetic material set the stage for one of the most important advances in the history of biology: the discovery of the _________ by James Watson and Francis Crick
The experiments on the nature of genetic material set the stage for one of the most important advances in the history of biology: the discovery of the _Three-dimensional Structure of DNA_ by James Watson and Francis Crick
26
Prior to Watson and Cricks discovery, most of the basic chemistry of DNA had already been determined by \_\_\_\_\_, \_\_\_\_\_, \_\_\_\_\_\_, _____ and others, who established that DNA consists of _____ and that each one contains a _____ a _____ and a \_\_\_\_\_\_
Prior to Watson and Cricks discovery, most of the basic chemistry of DNA had already been determined by _Miescher, Kossel, Levene, Chargaff_ and others, who established that DNA consists of _nucleotides_ and that each one contains a _sugar_ a _nitrogenous base_ and a _phosphate group_
27
In 1947 William Atsbury used a technique called ______ to study the three dimensional structure of DNA
In 1947 William Atsbury used a technique called _X-Ray diffraction_ to study the three dimensional structure of DNA
28
Atsbury's images did not provide enough resolution to reveal the structure of DNA, but \_\_\_\_\_\_, using the same technique, provided images critical in the eventual elucidation of the structure of DNA by watson and crick
Atsbury's images did not provide enough resolution to reveal the structure of DNA, but _Rosalind Franklin_, using the same technique, provided images critical in the eventual elucidation of the structure of DNA by watson and crick
29
What was the key to solving the structure of DNA?
Watson recognized that adenine bases bonded with Thymine bases and that Cytosine bases bonded with guanine bases - accounting for the ratios that Chargaff had discovered earlier
30
The model developed by Watson and Crick showed that DNA consists of two strands of _____ that run _____ and wind around each other to form a _____ with the ____ and ____ on the outside and the _____ in the interior
The model developed by Watson and Crick showed that DNA consists of two strands of _nucleotides_ that run _antiparallel_ and wind around each other to form a _right-handed helix_ with the _sugars_ and _phosphates_ on the outside and the _bases_ in the interior
31
What did Watson and Crick use to help solve the structure of DNA? a) X-ray diffraction images b) laws of structural chemistry c) models of DNA d) All of the Above
d)
32
in most organisms, _\_\_\_\__is the carrier of genetic information; a few viruses, however, use _\_\_\_\__ not DNA, as their genetic material
in most organisms, _DNA_ is the carrier of genetic information; a few viruses, however, use _RNA_ not DNA, as their genetic material
33
Who demonstrated that some viruses use RNA as genetic information carriers?
Heinz Fraenkel-Conrat and Bea Singer
34
It is useful to consider the structure of DNA at three levels of increasing complexity:
1. Primary 2. Secondary 3. Tertiary Structures of DNA
35
The primary structure of DNA refers to:
It's nucleotide structure and how the nucleotides are joined together
36
What does the secondary structure of DNA refer to?
It's stable three-dimensional configuration, the helical structure (discovered by Watson and Crick)
37
What does the tertiary structure of DNA refer to?
The complex packing arrangements of Doube-Stranded DNA in chromosomes
38
The primary structure of DNA consists of a string of ______ joined together by ________ bonds
The primary structure of DNA consists of a string of _nucleotides_ joined together by _phosphodiester_ bonds
39
DNA is a polymer (chain made up repeating units). What are the repeating units?
Nucleotides
40
What are the three parts that comprise a nucleotide?
1. Nitrogenous base (i.e. nitrogen-containing base) 2. phosphate group 3. a sugar
41
The sugars of nucleic acids (called _____ sugars) contain how many carbon atoms?
The sugars of nucleic acids (called _Pentose_ sugars) contain 5 carbon atoms.
42
How are the sugars in DNA and RNA different?
RNA: Called **ribose** has a hydroxyl group (OH) attached to the 2' carbon DNA: called **deoxyribose** has a hydrogen (H) at the 2' carbon (thus has one less Oxygen than ribose)
43
The additional oxygen in RNA has what effect?
Makes it more reactive (less chemically stable)
44
There are two types of nitrogenous base:
1. Purine 2. Pyrimadine
45
Each purine consists of a ______ attached to a \_\_\_\_\_
Each purine consists of a _6-member ring_ attached to a _5-member ring_
46
Each pyrimidine consists of a _______ only
Each pyrimidine consists of a _6-member ring_ only
47
What are the three pyrimidines common in nucleic acids?
1. Thymine (restricted to DNA) 2. Cytosine 3. Uracil (replaces thymine in RNA)
48
What are the two purines?
1. Adenine 2. Guanine
49
In a nucleotide, the nitrogenous base always forms a covalent bond with the ______ carbon atom of the sugar
In a nucleotide, the nitrogenous base always forms a covalent bond with the _1'-_ carbon atom of the sugar
50
What is a nucleoside?
Ribose or deoxyribose bonded to a nitrogenous base
51
How do the sugars of RNA and DNA differ? a) RNA has a six-carbon sugar; DNA has a 5-carbon sugar b) The sugar of RNA has a hydroxyl group that is not found in the sugar of DNA c) RNA contains uracil, DNA contains thymine d) DNA's sugar has a phosphorus atom; RNA's sugar does not
How do the sugars of RNA and DNA differ? a) RNA has a six-carbon sugar; DNA has a 5-carbon sugar **b) The sugar of RNA has a hydroxyl group that is not found in the sugar of DNA** c) RNA contains uracil, DNA contains thymine d) DNA's sugar has a phosphorus atom; RNA's sugar does not
52
DNA is made of many nucleotides connected by _____ bonds which join the _____ group of one nucleotide to the _____ group of the next nucleotide
DNA is made of many nucleotides connected by _covalent_ bonds which join the _5'-phosphate_ group of one nucleotide to the _3' hydroxyl_ group of the next nucleotide
53
The covalent bonds that connect nucleotides are called:
Phosphodiester linkages
54
What is a polynucleotide strand?
Series of nucleotides linked together by phosphodiester bonds
55
What is the 5' end?
End of a polynucleotide chain at which a phosphate group is attached to the 5'carbon atom of the sugar in the nucleotide
56
What is the 3' end?
End of a polynucleotide chain at which an OH group is attached to the 3'carbon atom of the sugar in the nucleotide
57
The polynucleotide strands of a DNA helix are antiparallel. What does this mean?
The orientation of the two polynucleotide strands of the DNA double helix in opposite directions (5' end of one is the 3' end of the other)
58
The two strands of DNA are held together by various molecular forces. _____ bonds link the bases on opposite strands
The two strands of DNA are held together by various molecular forces. _hydrogen_ bonds link the bases on opposite strands
59
Adenine normally pairs with thymine through ____ \_\_\_\_ bonds
Adenine normally pairs with thymine through _two hydrogen_ bonds
60
Cytosine normally pairs with guanine through _____ \_\_\_\_\_ bonds
Cytosine normally pairs with guanine through _three hydrogen_ bonds
61
The two polynucleotide strands of a DNA molecule are not identical, but are \_\_\_\_\_, which is important for efficient and accurate \_\_\_\_\_\_
The two polynucleotide strands of a DNA molecule are not identical, but are _complementary_, which is important for efficient and accurate _DNA replication_
62
The second force holding the two DNA strands together (recall the first is hydrogen bonds) is the interaction between the _____ \_\_\_\_ ____ in the interior of the molecule
The second force holding the two DNA strands together (recall the first is hydrogen bonds) is the interaction between the _stacked base pairs_ in the interior of the molecule
63
Stacking interactions of base pairs helps to ____ the DNA molecule
Stabalize
64
Concept Check: The antiparallel nature of DNA refers to: a) its charged phosphate groups b) the pairing of bases on strand with bases on the other strand c) the formation of hydrogen bonds between bases from opposite strands d) the opposite direction of the two strands of nucleotides
Concept Check: The antiparallel nature of DNA refers to: a) its charged phosphate groups b) the pairing of bases on strand with bases on the other strand c) the formation of hydrogen bonds between bases from opposite strands **d) the opposite direction of the two strands of nucleotides**
65
The three-dimensional structure of DNA described by Watson and Crick is termed the
B-DNA - right-handed helical structure of DNA that exists when water is abundant
66
DNA can also assume the A-DNA structure. what is this?
Right-handed helical structure of DNA that exists when little water is present
67
A third secondary structure of DNA is called the Z-DNA. Describe it
Secondary structure of DNA characterized by 12 bases per turn, a left-handed helix, and a sugar-phosphate backbone that zigzags back and forth
68
CONCEPT CHECK 8 How does B-DNA differ from Z-DNA
Z-DNA has a left-handed helix; B-DNA has a right-handed The sugar-phosphate backbone of Z-DNA zigzags back and forth whereas the backbone of B-DNA forms a smooth continuous ribbon

BIOL 207 Lecture (Genetics: A conceptual Approach 6th/7th Ed) (9 decks)

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