DNA Flashcards
What does DNA & RNA stand for
Deoxyribonucleic acid and Ribonucleic acid
Location of DNA (3) &RNA(4x2)
Nuclear DNA , mitochondrial dna
Chloroplastic dna
Nuclear rna ( forms here ) , ribosomal rna in ribosomes in cytoplasm ( functions here ), messenger rna in nucleus that leaves to attach to ribosome in cytoplasm Transfer rna found in cytoplasm
The make up of the Monomers that make up nucleic acids (1+ 3x2)
Nucleotides make up nucleic acids
Nucleotide are made up of nitrogenous bases( consisting of purines ( adenine and guanine) and pyrimidines( cytosine and thymine/ uracil) , sugar portion ( ribose in rna & deoxyribose in DNA) and phosphate portion
What makes up the chromatin network
Nuclear dna and proteins make up chromosomes that tangle and make up the chromatin network
Structure of Dna/ bonds / by who (2+1+1)
Structure of rna (difference to dna) ( 4)
Double stranded ( strands held together by weak hyrdogen bonds ) and natural shape is double helix This knowledge is based on a model brought forwards by james watson and francis crick
Single stranded, ribose sugar , uracil, bases are not paired
Functions of dna (2)
Function of rna (1)
Codes for formation of different proteins required in body.  responsible for transmitting hereditary characteristics from parents to offspring. 
Rna plays an important role in protein synthesis
Similarities(3) and differences (4) between dna and rna
S: sugar alternating with phosphate
Adenine, guanine and cytosine
Play role in protein synthesis , made of nucleotides
D: rna is single stranded
Ribose / deoxyribose
Thymine / uracil
Locations 
Define dna replication (1)
When and why does it occur ( 2 + 3)
Process by which dna makes an identical copy of itself
When : before cell division ( mitosis and meiosis ) during interphase
Why : identical copies of dna made to be shared amongst daughter cells during cell division so each daughter cell has same number of chromosomes w each other and original therefore identical to both after mitosis .
Process of dna replication ( 5/6)
Double helix unwinds
Weak h bonds between nb break and strands unzip
Each strand acts as template
Form new strand by attaching to free dna ncl in nucleoplasm to form complementary strands resulting in one og strand and one new & 2 genetically identical dna molecules
Process controlled by enzymes
What is a dna profile (4)
Pattens of black bars left on x-ray film when extract of dna is put through a special biotechnical process
Method of identifying individual by comparing his / her dna profile w another known dna profile
Uses of dna profiles
 diagnosis of inherited disorders identification of criminals in forensics science identifying relatives through paternity testing tracing siblings identifying dead people with unrecognisable bodies
Pros and cons against dna profiling ( 4x2 + 6)
Pros : can be applied to any human sample containing cells with nuclei , eg. saliva , semen & hair
Dna tests are extremely sensitive and can be conducted using samples too small for other serological tests
Dna is hardy & resists degeneration even after contamination with chemicals or bacteria
Excludes suspects in investigation therefore police are able to confidently drop line of enquiry and continue with investigation
Against :
Small piece is analysed and patter may not be unique to an individual
Dna profiling in labs might not meet standards
Human error in interpretation
Expensive
Unethical as it reveals personal information of disorders
Mistake iding causes trauma for family
Protein synthesis takes place in 3 stages :
Transcription , movement of mRNA out of the nucleus through nuclear pore into cytoplasm where it attaches to the ribosome , translation
Transcription
This is the Formation of messenger RNA ( mRNA )
Process : dna double helix unwinds , weak h bonds break and form 2 single strands w ONE acting as a template 2 form complementary strand mRNA using free RNA nucleotides from nucleoplasm
Codon (2)
3 adjacent sides on mRNA & codes for amino acid
