Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology > inquiry question 3 mod 5 > Flashcards

inquiry question 3 mod 5 Flashcards

(63 cards)

Start Studying
1
Q

what does DNA stand for

A

deoxyribose nucleic acid

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

DNA

A

Hereditary material that carries all the genetic code for proteins that enable cells to undergo growth, repair and other specialised functions

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

location of DNA

A

prokaryotes: stored as single looped chromosomes + smaller loops of DNA (plasmids)
eukaryotes:
- nucleus, chloroplast, mitochondria

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

structure of DNA

A
  • double stranded helix with 4 nitrogenous bases
  • long double stranded helix
  • chain made up of nucleotides
  • leading strand 5’ - 3’
  • lagging strand 3’ to 5’
  • anti-parallel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

nucleotides

A

made up of
- deoxyribose sugar
- phosphate group
- nitrogenous base
- base pairs bonded by hydrogen bonds
- covalent bonds between sugar and phosphate group

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

deoxyribose sugar

A
  • five carbon atoms
  • four carbons and one oxygen forms a ring + one carbon branching off
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

nitrogenous bases in DNA

A
  • adenine, thymine, guanine, cytosine
  • purine (two rings) adenine and guanine
  • pyrimidine (one ring) cytosine and thymine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

enzymes needed for DNA replication

A

helicase, polymerase, topoisomerase, primase, rna primers

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

DNA replication

A
  • DNA must replicate before a cell divides (mitosis)
  • takes place in interphase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

DNA replication steps

A
  1. Helicase unwinds and separates/unzips the 2 DNA strands into a replication fork (Y shape) –> breaks hydrogen bonds between bases
  2. bind proteins attach to the 2 DNA strands → keeps them separate and untwisted
  3. Enzyme topoisomerase relieves stress (caused by the unzipping) –> attaches ahead of the fork on the DNA molecule → prevents coiling so it can continue to separate
  4. primase makes RNA primers
  5. RNA primers are required to add new nucleotides from the surrounding cytoplasm
  6. DNA polymerase add new nucleotides to the replication fork stands
    - leading strand –> Bind to DNA → moves along → reads bases → assemble complementary strand of nucleotides
    - lagging strand –> discontinuous segments (okazaki fragments) glued together by DNA ligase
    - bases are paired
  7. new strand is created –> complementary of one of the template strands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what model is DNA

A

semi conservative –> watson and crick

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

leading strand: direction and enzymes needed

A

5’ to 3’
- DNA helicase
DNA polymerase
- Primase
- topoisomerase

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

lagging strand: direction and enzymes needed

A

3’ to 5’
- primase
- polymerase
- ligase
- helicase

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

role of DNA helicase

A

unwinds and separates/unzips the 2 DNA strands into a replication fork (Y shape)
which is done through breaking hydrogen bonds

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

Role of topoisomerase

A

relieves stress (caused by the unzipping) → attaches ahead of the fork on the DNA molecule → prevents coiling so it can continue to separate

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

role of primase

A

required to add new nucleotides from the surrounding cytoplasm

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

role of DNA polymerase

A

add new nucleotides to the replication fork stands

leading: binds to DNA –> moves along and reads bases -> assemble complementary strand of nucleotides

lagging: synthesises okazaki fragments

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

role of DNA ligase

A

glues the Okazaki fragments together in the lagging strand

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

okazaki fragments

A

short sections of DNA formed at the time of discontinuous synthesis of the lagging strand during replication of DNA

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

similarities in prokaryotes and eukaryotes

A
  • DNA replicates before cell division
  • DNA is combined with proteins
  • they have the same role to make polypeptides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

differences in DNA –> eukaryotes and prokaryotes

A

prokaryotes:
- little non-coding DNA
- circular chromosome in nucleoid region
- one copy of each gene
eukaryotes:
- large section of non-coding DNA
- densely packed in nucleus as linear chromosomes
- multiple copies of each gene

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

what is a gene in terms of DNA

A

length of a DNA

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

polypeptides

A

amino acid chains –> 20 amino acids joined by peptide bonds
- they fold to create a functional protein

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

amino acid structure

A

oxygen, carbon , hydrogen , nitrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
non-coding DNA
introns --> spliced out (which helps regulate gene expression) promoters --> TATA box
26
examples of proteins
keratin, haemoglobin
27
coding DNA
exons
28
2 steps of protein synthesis
1. transcription - base sequence is transcribed into mRNA 2. translation - polypeptides are made from mRNA
29
what does RNA stand for
ribonucleic acid - ribose sugar in the back bone - uracill instead of thymine - single stranded three types: - mRNA (messenger) - rRNA (ribosomal) - tRNA (transfer)
30
role of mRNA
- copied DNA code - carries genetic information to the ribosome
31
role of rRNA
- site of protein synthesis - single strand - globular shape - reads the mRNA sequence --> translates genetic code into amino acids
32
role of tRNA
transfers amino acids to ribosomes where proteins are synthesised - clover leaf shape - single stranded molecule with attachment site at one end with amino acid - opposite end has an anti codon --> three nucleotide bases UAG (mRNA) AUC (tRNA)
33
RNA
converts genetic information contained within DNA to build proteins
34
mRNA
- long single straight chain of nucleotides that carries information for a specific protein - bases: ( A,U,G,C) - made up of codons
35
codon
sequences of three bases AUG start
36
anti-codon
complimentary of the codon (A - U ) (C - G)
37
protein synthesis
production or synthesis of polypeptide chains
38
role of transcription
Process by which the DNA base sequence is read by the enzyme RNA polymerase and copied onto a single strand of mRNA
39
characteristics of transcription
- requires RNA polymerase to build in the 5' to 3' - base sequence from template strand is transcribed onto mRNA - mRNA needs to be processed before leaving the nucleus - takes place in the nucleus -tata start stops at stop codons
40
direction of transcription
5' to 3'
41
what enzyme does transcription need to build in the 5' to 3' direction
RNA polymerase
42
how do you know where transcription starts
TATA box
43
where does transcription end
stop codons
44
direction of coding strand
5' to 3'
45
direction of template strand
3' to 5'
46
coding strand
contains the gene
47
template strand
U instead of T in mRNA
48
transcription stages
initiation elongation termination
49
transcription process
1. Specific section of DNA continuing the gene of interest is unwinded, exposing the DNA base sequence through RNA polymerase which binds to DNA and separates the DNA strands 2. RNA polymerase then uses one strand of DNA as a template to assemble the nucleotides into RNA in the 5’ to 3’ direction Initiation stage: promoters (TATA box) show where the polymerase must bind to begin transcription of RNA Elongation stage: RNA polymerase builds a new strand in the 5’ to 3’ direction → through adding RNA free floating mRNA nucleotides (A,U,C,G) to undergo complementary base pairing in 5’ to 3’ direction Termination stage: Specific base sequences → codons signal the process to stop → termination signal mRNA processing RNA editing needs to be done to the nucleotide chain to makes the RNA FUNCTIONAL - Introns - spliced out mRNA editing Exons rejoined by ligase - Guanine triphosphate cap is added to the 5’ end of new mRNA - Poly A tail is added to 3’ end of RNA mRNA transcript Mature mRNA leaves nucleus through pores → goes to ROUGH ER ribosomes
50
exons
segments of DNA that code for proteins
51
why and where and what is guanine triphosphate cap and poly A tale
To protect the mRNA from being broken up while leaving the nucleus in mRNA editing stage - guanine triphosphate cap --> 5' side - poly A tail --> 3' side
52
what is used to protect the mRNA from being broken up while leaving the nucleus
guanine triphosphate cap 5' poly A tale 3'
53
stages in translation
initiation elongation termination
54
role of translation
Process of decoding mRNA into polypeptide chain that will ultimately become a protein
55
translation characteristics
- occurs in the cytoplasm - requires ribosomes and tRNA - starts at AUG - ends at stop codon - polypeptide chain processed folded 1. initiation - AUG: start codon on mRNA 2. elongation 3. termination - stop codon on mRNA
56
initiation translation
- Small subunit attaches to large ribosomal subunit mRNA transcript attaches onto a ribosome in the cytoplasm - mRNA transcript begins at AUG - Ribosome reads one codon at a time
57
elongation translation
- ribosomes continue to read codons - recruits tRNA molecules - codons on mRNA are matched to anti-codons on tRNA - tRNA molecule drops off respective amino acid to the sit - amino acid is covalently bonded (peptide bonded) to previous acid in line - process continues to form a long chain of amino acids
58
termination translation
Growth of amino acid chain ceases when the stop codon is reached
59
what does a polypeptide need to do in order to become a functional protein
fold into the correct 3D shape
60
gene expression
Process by which information encoded in a gene is used to direct the assembly of a polypeptide or protein
61
gene expression
Process by which information encoded in a gene is used to direct the assembly of a polypeptide or protein
62
difference in protein synthesis and DNA replication
DNA REPLICATION IS USED TO MAKE ADDITIONAL COPIES OF GENETIC MATERIAL IN PREPARATION FOR MITOSIS OR MEIOSIS WHEREAS PROTEIN SYNTHESIS INVOLVES THE EXPRESSION OF GENES INTO POLYPEPTIDE CHAINS
63
how are genes regulated
turning genes on or off which determines the structure and function of cells - Important as not all proteins are needed all the time due to changing environmental conditions in the body

biology (11 decks)

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