Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Economics > Biology - Module 6 > Flashcards

Biology - Module 6 Flashcards

1
Q

What are the top 3 dangerous ionising radiation sources?

A

UV rays, X-rays, Gamma rays

These types of radiation are known for their potential to cause harm to biological tissues.

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

What can electromagnetic radiation produce that affects DNA?

A

Free radicals

Free radicals are unstable molecules that can cause damage to DNA and other cellular structures.

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

How does direct ionising radiation affect DNA?

A

It frees electrons from DNA molecules, causing damage

High energy electrons can lead to structural changes in DNA.

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

What happens during indirect ionising radiation’s interaction with water?

A

Electrons interact with water and release free radicals

This process creates reactive molecules that can damage DNA.

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

What are the consequences of free radicals on DNA?

A

Break strands of DNA, deletions, partial chromosome loss, cross linking of DNA

These effects interfere with normal cellular functions, including protein synthesis.

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

True or False: Ionising radiation can only damage DNA directly.

A

False

Ionising radiation can cause damage both directly and indirectly.

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

Fill in the blank: Ionising radiation can cause _______ in DNA which interferes with protein synthesis.

A

breakage

The breakage of DNA strands disrupts the genetic instructions necessary for protein synthesis.

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

What type of radiation do UV rays represent?

A

Ionising radiation

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

How do UV rays cause mutations?

A

By creating free radicals and producing pyrimidine dimers

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

What are free radicals?

A

Highly reactive molecules that cause breakage in DNA strands

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

What are pyrimidine dimers?

A

Two or more pyrimidine bases attached together on the same DNA strand

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

Which bases are considered pyrimidine bases in DNA?

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

What is the effect of pyrimidine dimers on DNA replication?

A

They confuse DNA polymerase, leading to incorrect DNA replication

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

What type of cancer is primarily caused by UV rays in Australia?

A

Skin cancer

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

In which type of cells do mutations occur that lead to skin cancer?

A

Somatic cells

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

What gene is mutated leading to uncontrollable cell growth in skin cancer?

A

Tumour suppressor gene

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

What type of tumour can form due to mutations caused by UV rays?

A

Melanoma

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

Fill in the blank: UV rays can create free radicals from _______.

A

[water molecules]

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

True or False: UV rays only cause mutations by creating free radicals.

A

False

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

What are chemicals that will cause mutations with high frequency or long-term exposure?

A

Intercalating agents and Base analogues

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

What is an example of an intercalating agent?

A

Ethidium Bromide

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

What is the primary use of ethidium bromide in molecular biology?

A

Fluorescent tag in gel electrophoresis

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

How does ethidium bromide visualize DNA during electrophoresis?

A

By staining DNA through intercalation into the double helix

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

What do intercalating agents do to DNA?

A

Insert themselves into bonds between base pairs and alter the DNA shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the effect of ethidium bromide on DNA replication?
Leads to errors in replication
26
What happens to DNA when ethidium bromide binds to it?
Deformation of DNA occurs
27
What biological processes are affected by ethidium bromide?
DNA replication and transcription
28
What are the symptoms of exposure to ethidium bromide?
Irritation of the mouth, upper respiratory tract, skin, and eyes
29
Why is ethidium bromide often not used as a dye?
It is a toxic mutagen
30
What are base analogues?
Chemicals structurally similar to nitrogenous bases
31
What is an example of a base analogue?
5-Bromouracil
32
How does 5-Bromouracil affect DNA replication?
It is incorporated instead of thymine
33
What property of 5-Bromouracil causes it to bind preferentially to guanine?
It is more electronegative than thymine
34
What can result from the incorporation of 5-Bromouracil into DNA?
Creation of a faulty protein
35
What is one way chemicals can damage DNA?
Accidental incorporation into DNA instead of proper nucleotides
36
What does actinomycin D do to DNA?
Inserts itself and creates a bulge, preventing replication
37
What is the effect of dimethyl sulfate on DNA?
Creates a gap by breaking the bond between base and sugar
38
What are naturally occurring mutagens?
Exposure to microbes, plants, and animals that can cause mutations ## Footnote This includes various environmental factors that can induce genetic changes.
39
What is Helicobacter pylori?
A bacteria that can enter the body from food, water, or utensils and lives in the digestive tract ## Footnote H.pylori is associated with various gastrointestinal diseases.
40
In which countries is the presence of H.pylori more common?
Countries that lack clean water, sanitation, and proper sewage systems ## Footnote Poor public health infrastructure increases the risk of infection.
41
How can H.pylori enter one's body?
Contact with saliva or bodily fluids of infected individuals ## Footnote This highlights the communicable nature of the infection.
42
What feature of H.pylori helps it survive extreme pH levels?
A thick cell wall ## Footnote This adaptation allows it to thrive in the acidic environment of the stomach.
43
What role do pili play in H.pylori?
Help in holding onto cell walls in the body and moving around ## Footnote Pili are crucial for bacterial adhesion and colonization.
44
What happens when H.pylori enters the stomach?
It leads to chronic inflammation due to the host's inability to eradicate the bacteria ## Footnote Chronic inflammation can have several detrimental effects on health.
45
What are free radicals?
Atoms that have lost an electron, making them unstable and reactive ## Footnote Free radicals can cause damage to cells and DNA.
46
How do free radicals contribute to mutations?
They attack gastric epithelial cells and break bonds in DNA, leading to frameshift and point mutations ## Footnote This process is a key mechanism in the development of cancer.
47
What effect does aging have on the body's ability to fight free radicals?
The body gradually loses its ability to fight free radicals ## Footnote This loss increases the risk of cellular damage over time.
48
What can ulcers lead to?
Stomach cancer ## Footnote Ulcers create conditions that may allow for further bacterial infection and genetic changes.
49
How does H.pylori contribute to stomach cancer?
It attacks and destroys the lining of the stomach by gradually mutating and breaking down gastric epithelial cells ## Footnote The gastric lining is essential for protecting the stomach from acid.
50
What happens when stomach acid penetrates through the lining of the stomach?
It leads to ulcers in the stomach or the upper part of the small intestine ## Footnote This can result in serious gastrointestinal complications.
51
What is a point mutation?
A change in just one nucleotide (the basic unit of DNA/RNA) that can affect the final protein produced.
52
What is a substitution mutation?
One nucleotide is swapped out for another.
53
Provide an example of a substitution mutation.
Original DNA: ATG CCG → Mutated DNA: ACG CCG (T is replaced with C)
54
What are frameshift mutations?
Mutations that shift the way codons are read, changing everything downstream from the mutation.
55
What is insertion in the context of mutations?
Extra bases are added, shifting the reading frame.
56
Provide an example of an insertion mutation.
Original DNA: ATG CCG → Mutated DNA: ATG ACC G (A is inserted)
57
What is deletion in the context of mutations?
A base is removed, also shifting the reading frame.
58
Provide an example of a deletion mutation.
Original DNA: ATG CCG → Mutated DNA: ATG CG (One C is deleted)
59
How does DNA get translated into proteins?
DNA is transcribed into mRNA and then translated into proteins.
60
What is a silent mutation?
A mutation that does not change the amino acid sequence due to redundancy in the genetic code.
61
Provide an example of a silent mutation.
Original mRNA Codon: GGU (codes for glycine) → Mutated mRNA Codon: GGC (also codes for glycine)
62
What is a missense mutation?
A mutation that changes one amino acid to another.
63
Provide an example of a missense mutation.
Original Codon: GGU → Glycine; Mutated Codon: GAU → Aspartic Acid
64
What is a nonsense mutation?
A mutation that introduces a stop codon, stopping translation early.
65
Provide an example of a nonsense mutation.
Original Codon: UAC (codes for Tyrosine) → Mutated Codon: UAA (STOP codon)
66
What is a neutral mutation?
A mutation that changes the amino acid, but the new one is chemically similar to the original.
67
Provide an example of a neutral mutation.
Original Amino Acid: Glutamic Acid; Mutated Amino Acid: Aspartic Acid (both negatively charged)

Economics (3 decks)

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