bio unit 2 quiz 1 Flashcards
what is DNA
- stands for Deoxyribnuleci Acid
- molecule that contains genetic info
- carries instructions for proteins for growth development, repair and daily things
- is universlal
where is DNA found
nuclues in eukartic and cytoplam in prokayotics
DNA order
1- stores info as a code
2- sopies info to pass it to next cells
3- uses code to make proteins ( the protiens give the traits)
polymer and monomenr od DNA
DNA is a nucleic Acid made of 2 repeating chian of nucleotides. DNA is the polumer and the nucleotides is the monemers.
parts of a nucletodie
the phosphate gorup, a sugar called deoxyribose, one of the 4 nirtogen bases (A,T,C,G)
structure of DNA
- has a double helix structure like a twisted ladder
- sides are phoosphate groups
- rugs of ladder made of paried nitorogen bases
- top 5 prime and 3 prime
bottem 3 prime and 5 prime ] its antiparell - stble and stays in nucleues
covelent bonds
bonds between sugar and phosphate. very strong
hydrgen bonds
bonds between nitrogen bases, weak. the nirtogen bases have pairing with coplementray bases
pairing
A=T
G=C
what does the structure of the DNA allow it to do
store and replicate genetic info
genes and proteins
- DNA has genes which are segments of the DNA that code for prteins
- proteins determine the traits of an orgism
- the nitorgens bases forms a code that is read to create proteisn
Who found DNA
Watson and Crick stole the DNA structure from Rosalind Franklind, who used x-ray difraction to find its structure.
origin of DNA
- DNA came from RNA, RNA was mutated to create DNA.. hypothiese that RNA as the first gentic material. thinks that it may have occured from deep sea thermal vents, or chemical reaction from lighting,
DNA replication
- process where molecule makes a copy of itself, to make sure that each new cell gets an exact copy of the DNA.
Semi-conservitaive process
new DNA molecules are made of half original strands, and half new strands
the actual process of cell division
- happens in the s phase of the cell cycle
- DNA is unzipped by the enzyme helicase, by undoing hydorgen bonds
- free floating nucleotides move to unpaird bases
- DNA polymerse enzyme makes covalent bonds bettwen nucleotide, which creates a new strand
gene expression
process by which info from gene is used to make a protein( which are traits)
- has 2 big steps : transcription and trnslation
- also known as central dogma
RNA
- ribonucleic Acid
- is a single strnaded molecule
- made up of RNA nuclrotides
- has ribose sugar instrad of dibrocrose
- the nitrogen bases are U,G, C, A
- carries gentic info to ribosomes for proteins synthesis
- less stable
- leaves nuclues
A, U, T
adenien, Uracil, Thymine
G, C
guanine, cytosine
mrna
carry message to ribose on how to make protein
trna
trnafers amino acids to ribosome
rrna
is part of the ribose
transcription
- process where MRA sequence is produced from DNA template,. So DNA to mRNA called mran transcript.
process of trnascitption
1) a gene unzips by RNA polumerse
2) RNA nucleotides are added to complemetry DNA
3) single strnaded mRNA is created, which seprates from DNA and goes to cytplsm
4) the 2 strands of DNA come back together
- occues in the nucleus
translation
pricess where the code in mrna is translated into of amino acids on a plypeptide chain = protein
so mrna to protein
translation process
1) mrna arrives at ribose and it code does the trnaslation process
2) anti codons in tra bring amino acds and pair with the corret codon in mrna
3) rrna in the ribosome guides the mrna and the trna to join the amno aics to form a protein on the mran condon
4) this process will kep happnieng until a stop condon is reached where the process stops and the polypeptide chin is realeased.
condon
- a set of 3 nitrogen bases on MRNA
- each triplet codes for one amino acid
anticodon
a set of 3 nucleotides that is complementry to an mrna. this attachs to the codon.
gene expression as a regulated prcess
- gene rexpression can be turned on and off
- orginms alter their pattern of gene expression in response to changes in the envirment
gene mutation
change in nitogen base of a section of DA for a protein
wild type = before mutiation
mutant = after mutation
sometimes the DNA can get instructions to self destruct or apotosis
gene mutation results
good as they can crete new variatios of traits, bad can create someting bad like diese or stop normal function, or can have no effect.
poitn mutation
change in sigle bases alos called subsitiution. will affect one codon. if a point mutaion does not cause chage to the aminoacid sequence than its a silent mutation
frame shift
happens when a base is added or deleted. this will affect every condon after this. the 3 groups will change.
which one is added or taken away
sickel cell anemia
- point mutioan
- glu is replaced with val which caues the
- wich causes the boold cell to be a bannana shape
- cna cause tumers/ clumps
mutaltions on a pouplation
- will create genetic diversity, will increase tth chnaces of survival. leads to evolution
germline mutation
- are inherited
- changes in DNA that is inherited from the egg or sperm or gametes
somatic mutation
cahnges in DNA hat happen to orther cells, such as body cells.
causes of muation
- DNA does not replicate pefectl
- outside facotrs can cause mistakes.
