DNA Flashcards
Transcription Vs. Translation
rewriting in the same language- IN NUCLEUS
Genes are nucleic acid chains in DNA double helixes
rewritten to form of messenger mRNA
IN CYTOPLASM-rewriting in different language,
mRNA instructions to form amino acids-protein synthes
LIFE
What are the structure of genes
4 nitrogenous bases L/T -A:T, G:C
4 nucleotides- form Double helix nucleic acid chains
sequence of nucleotides along a DNA strand
What are the differences between purines and pyrimidines?
Purines-adenine & guanine -2 nitrogen rings
P.A.G
Pyrimidines- thymine & cytosine - 1 nitrogen ring
Base match- AT and GC
What are the steps in transcription?
DNA strand unzipped by helicase= 2 strands
1- non-coding strand (antisense) and
1- coding strand (sense strand)
What enzyme initiated transcription?
RNA polymerase
Compare exons and introns
Exons are retained protein-coding regions - 3 bases together on RNA= aa
Introns are regions between exons that are spliced
**NO introns on mRNA
Describe an endonuclease
recognizes local distortions of DNA and cleaves it
Describe mitochondrial DNA
mother only.
double-stranded closed circle, containing 37 genes
How many nucleotides are needed to code for an amino acid?
3 in a codon
amino acid is product of gene translation
Like computer 0,1/genotype, pictures on computer are phenotype/amion acids
Describe how RNA structure is different from DNA
RNA
1] Single stranded, vulnerable also enters cytoplasm,
2] Ribose sugar instead of deoxyribose,
3] Thymine replaced by uracil (T -> U)
What are the 3 types of RNA?
1] messenger RNA-from DNA, replication, carries the instructions to cytoplasm.
2] transfer RNA-reads, delivers 3-codon/aa code to rRNA matched aa of mRNA to form chain
3]ER- ribsosomal RNA-translates the instructions to form long chain protein. tRNA bind to mRNA codon- form a protien.
What is the most significant nitrogenous waste
metabolism of DNA
What are the steps in Translation?
1] The introns are removed and the final mRNA leaves the nucleus to finds ribosomes.
2] Ribosomal RNA on ribosome participates in the assembly of amino acids from mRNA code
WHat is gene expression
Refers to activity of genes
Induction- increasing expression, usually by an exogenous agent, ex a drug
Repression-prevention of expression
Operons- promoter sites and structural genes that regulate expression of genes
WHat happens during gene expression when accident of DNA duplication?
Mutation
***Inherited mutations- ONLY germ cell DNA duplication accidents and carries genetic information
Somatic mutations are fatal to embryo
Describe disease in terms of genetics
combination of susceptibility and environment.
Genetic disorders- inherited trait of germ line mutation.
Some acquire over time via mutations are acquired
In terms of a neoplasm is that a inherited or acquired mutation?
Mostly acquired
Thryoid cancer- exposure to radiation
What is inherited in terms of neoplasms?
susceptibilty or probablity that neoplasms may occur
How many chromosomes are inherited from each parent?
23 one strand from each parent
to make 46 total chromosomes
Compare the results of meiosis and mitosis
Meiosis: is the process by which we get 4 haploid cells from parent
1 parent
Mitosis 1-replicat-2 daughter cells
4-haploid
Mitosis: cloning the original cell and get 2 full compliments of DNA - 2 daughert
What is 3codon/protein structure that we all carry?
Genotype
multiple genotypes for one presentation =polygeneic inheritance- most dz and traits
carriers of genetic mutations in genotype may not express their traits to the same degrees
What are the physical genetics seen? Why are some phenotypes not expressed?
Phenotype
recognizable traits seen
specific
more than one genotype associated with it
What is the ability to express itself?
Penetrance by a gene
high penetrance = more noticeable.
What is each gene mutually dependent on the other?
Complimentary genes
