Unit 1 Key Area 1-3 Flashcards
What is DNA is composed of
Two chain of nucleotide
Base pairing rule
Adenine pairs with thymine
Guanine pairs with cytosine
Definition of a nucleotides
They are comprised of deoxyribose sugar, phosphate and a base
What the name of the bond between the deoxyribose sugar and phosphate
Sugar- phosphate bond
What are the bonds between the bases called
Weak hydrogen bonds
Two classification of cells
Prokaryotes
Eukaryotes
Where are mitochondria and chloroplast DNA inherited from
From the mother
Are mitochondria dna circular or linear
Circular
DNA is inside of what
Chromosomes
Two types of strands
Lagging and leading
DNA replication is
Semi-conserivate
What does semi-conserivate mean
It has one old parental strand and one new one
Where do polymerase add nucleotides
At the 3’end
In the leading strand
Dna polymerase adds complementary DNA nucleotides to thr lead strand continuously
Stages of the leading strand
- The weak hydrogen bonds break and the DNA unzips
- A DNA primer binds to the end of the 3’ to allow polymerase to add the DNA nucleotide
- Individual nucleotides aline wirh there complementary base. They become joined 3’ end of the primer.
Polymerase brings about thr formation of the sugar-phosphate bind between the primer and nucleotide.
How does lagging strand work
DNA polymerase adds complementary nucleotides to lagging strand in fragments
What sort of process is lagging strand
Discontinuous
What does ligase do
Seals the fragments together in the lagging strand
Where do primers bind yo leading strand
At the bottom in one place
At the 3’ end
Where do primer add to at the lagging strand
They bind at many places
DNA replication requirement
DNA
primer
Nucleotides and bases
DNA polymerase and ligase enzymes
A supply of atp
What does PCR allow
A specific section of DNA to be amplified in vitro
Steps of PCR
Step one. DNA is heated to 95°c this causes DNA to denatured and the strands separate
- DNA is cooled to 55°c for a few seconds. This allows primers to to bond to the separated DNA strands
- DNA is heated up to 75°c this allows heat-tolerrant DNA polymerase to replicate the dna be adding nucleotides to the 3’ of thr original DNA
How many times is PRC repeated
20-30 cycles
What is amplification
Doubling DNA
Uses of PCR
Forensic science
Disease detection
Requirements for PCR
Sequence specific primer
Supply of nucleotides
DNA sample
DNA polymerase
Thermocycler
What our 3 differences between DNA and RNA
RNA is single strand and DNA is double stranded
RNA ribose sugar and deoxyribose is DNA
Uracil is RNA and DNA is thymine
Three types of rna
Messager RNA mRNA
transfer RNA tRNA
Ribosomal RNA rRNA
MRNA
Mrna is formed jn the nucleus from free nucleotides and carries a copy of thr dna code from the nucleus to the Ribosome where proteins are made
Trna
Molecules collect amino acids and bring them to the Ribosome to build proteins into a 3d structure held together hu hydrogen bonds
RRNA
Molecules combined with proteins to create the ribosomes. The organelle responsible for assembling proteins following DNA code
Are the two strands of dna parallel or anti parallel
Antiparallel
Are the two strands of dna parallel or anti parallel
Antiparallel
What does antiparaelle mean
Each strand runs in the opposite direction of thr complementary
What type of backbone do they have
A sugar phosphate backbone
What type of backbone do they have
A sugar phosphate backbone
What’s the bond between phosphate and deoxyribose sugar
Sugar phosphate bond
What is at the 5’ end
Phosphate
What is at the 3’ end
Deoxyribose sugar
What time of chromosomes are in eukaryotes
Linear chromosomes
Type of eukaryotes
Plants, animals and fungal
One structural difference between eukaryotes and prokaryotes
Eukarytoes are a nucleus
In what places in rhe cell so eukarytoes have circular chromosomes
Mitochondria and chloroplast
Where is dna found in the prokartoes
Cytoplasm and plasmid
What type of chromosomes do prokarytoes have
Circular
Yeast cells
Have circular chromosomes in the plasmid and cytoplasm
How is the DNA stored
They are tightly coiled and packaged around histone proteins
Step 1 in DNA Replication
The DNA parental strand composed of two complementary strands unwind
Step 2 in DNA replication
The weak- temporarily hydrogen bind between bond break
Step 3 in DNA replication
Two new template strands form exposing bases. The DNA strands separate
Step 4 DNA replication
Primers attach to the 3’ end and free nucleotides bind wirh their base pair by new weak tempary hydrogen bonds