Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology 120 > Chapter 12 > Flashcards

Chapter 12 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

How was DNA discovered and by whom?

A

Swiss chemist named Johann Friedrich Miescher collected pus cells from bandages and extracted large quantities of an acidic substance with lots of phosphorus and named it nuclein (DNA)

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

What was the final experiment that proved DNA held genetic material over protein?

A

They injected bacteriophages into E. coli, one with proteins tracked and one with DNA tracked and the end resulted in DNA carrying all the genetic material

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

What is transformation?

A

The conversion of a cells hereditary type by the uptake of DNA released by the breakdown of another cell

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

What are the components of a nucleotide in DNA?

A
  • One of four nitrogenous bases: Adenine, Thymine, Cytosine, Guanine
  • a five carbon sugar called deoxyribose (labeled 1’ to 5’)
  • a phosphate group (PO4 with a double bonded O)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which two nitrogenous bases are purine? Which are pyrimidines?

A

Purine- adenine and guanine

Pyrimidine- thymine and cytosine

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

What are chargaff’s rules?

A

The relationships that show the amount of purines equals the amount of pyrimidines, and the amount of adenine equals the amount of thymine and same for guanine and cytosine

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

What is the sugar phosphate backbone?

A

The backbone of nucleotides that is a sugar connected to a phosphate group connected to a sugar and so on. The nitrogenous bases connect to the 1’ carbon of sugars

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

What is a phosphodiester bond?

A

The bond of sugars by phosphate groups connecting to the 3’ of a top sugar to the 5’ of the bottom sugar

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

Are the two ends of nucleotides the same? If not how are they different?

A

They are not
3’ ending has a hydroxyl group at the end (newest end)
5’ ending has a phosphate group (oldest end)

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

What connects the nitrogenous bases in the double helix model of DNA?

A

Hydrogen bonds connect purines and pyrimidines

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

What are the primary enzymes of DNA replication?

A

DNA polymerases

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

What’s the difference between semiconservative replication, conservative replication, and dispersive replication?

A

Semi- normal replication results in half parent half replicated then once replicated again results in two fully replicated and two half and half
Conservative- replicates then parents go back to parents and replicated strands link up so you have one fully parental and one fully replicated then when replicate again you result in 3 fully replicated and one fully parental
Dispersive- replicated in chunks so there’s no fully parental or fully replicated

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

What is the sliding DNA clamp?

A

A protein that encircles the DNA and bonds to the rear of the DNA polymerase
It tethers the DNA polymerase to the template strand

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

What are the 4 key molecular events of DNA replication?

A
  1. Two strands of DNA unwind for replication to occur
  2. DNA polymerase can add nucleotides only to an existing chain
  3. The overall direction of the new synthesis is in the 5’ to 3’ direction (antiparallel to template strand)
  4. Nucleotides enter into a newly synthesized chain according So A-T and C-G
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are single stranded binding proteins?

A

Proteins that coat the exposed single stranded DNA segments, stabilizing the DNA and keeping the two strands from pairing back together

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

What is topoisomerase?

A

An enzyme that cuts the DNA ahead of the replication fork then turns the DNA on one side of the break in the opposite direction of the twisting force and rejoins the two strands

17
Q

What are primers?

A

A short chain of a few nucleotides that comes into play when DNA polymerases can’t add nucleotides to a new strand where no existing strand is in place (DNA polymerase can only add nucleotides to 3’ end of existing strand)
The primer gets synthesized by primase

18
Q

What is the leading strand template of DNA replication?

A

It is the template that goes from 3’ to 5’ and has continuous replication on it

19
Q

What is the lagging strand template of DNA replication?

A

It is the template that grows in the 5’ to 3’ direction and has discontinuous synthesis in the opposite direction

20
Q

What are Okazaki fragments?

A

The short lengths that fill the lagging strand

21
Q

What is the unwinding enzyme in DNA replication?

A

DNA helicase

22
Q

What is DNA Ligase?

A

Seals the nick left eternal adjacent bases after RNA primers replaced with DNA

23
Q

What’s the difference between DNA polymerase I and DNA polymerase III?

A

I- removes the RNA of the previously synthesized Okazaki fragment and replaces rna nucleotides with DNA nucleotides
III- main replication enzyme of E. coli
Extends RNA primer by adding DNA nucleotides to it

24
Q

What is a telomere?

A

A region of noncoding DNA that consists of a short DNA sequence that is repeated hundreds of thousands of times
Can help prevent cancer

25
Q

What are DNA repair mechanisms?

A

They are mismatch pair mechanisms that increase the accuracy of DNA replication well beyond the one in a million errors that persist after proofreading

26
Q

What are mutations in DNA?

A

Differences in DNA sequence that appear and remain in the replicated copies

27
Q

What are histones? What are the five types?

A 
A class of small positively charged proteins that are complexed with DNA in the chromosomes of eukaryotes 
H1, H2A, H2B, H3, H4
28
Q

What are non histone proteins?

A

All the proteins associated with DNA that are not histones

Most are negatively charged or neutral

29
Q

Which organizes DNA more simply? Prokaryotes or eukaryotes?

A

Prokaryotes

30
Q

What is the role of Histone H1? Compared to H2A, H2B, H3 and H4?

A

Brings out chromatin packaging

The other pack DNA into nucleosome

Biology 120 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions