Bio Unit 4: DNA/RNA, protein synthesis, mutations

building blocks of protein

amino acids (end in -ide)

tRNA word

anticodon (opposite of codon)

frameshift mutation

base is added in or deleted, so the reading frame is shifted many amino acids change, protein could end early or make it extra long

Chargaff

certain bases always occur in a 1-1 ratio: A-T and C-G

How do mutations affect the outcome of protein synthesis?

change order of bases in DNA or RNA, so number of proteins produced is changed

What are mutations?

changes in DNA/ RNA sequence

DNA word

code

mRNA word

codon

Where does translation happen?

cytoplasm and ribosomes (made of protein and rRNA)

spontaneous (random change): cause of mutations

during DNA replication (copying) when cells divide, during transcription (DNA --> mRNA)

short protein

early stop

Wilkins and Franklin

experiments, x-ray diffraction

DNA model

hydrogen bonds, base pairs (nitrogen bases A-T and G-C), nucleotide (phosphate, sugar, and base), sugar (deoxyribose), phosphate

photo 51

image taken by Rosalind Franklin that revealed the double helix in DNA, essential to the identification of the structure of DNA

chromosomal mutation

large sections of DNA are flipped around, duplicated/ copied, removed, etc not just one base! hundreds if not thousands

What is translation?

mRNA is changed into protein

similarities between DNA and RNA

nucleotides as building blocks, sugar-phosphate backbone, nitrogen bases (a, c, g, and other)

building blocks of DNA

nucleotides: deoxyribose, nitrogen base, phosphate

building blocks of RNA

nucleotides: ribose, nitrogen base, phosphate

Where does transcription happen?

nucleus (DNA can't leave nucleus bc it's too big)

How can mutations be hereditary?

occur in sex cells, sperm or egg, aka gamete

missense mutation

one base changes and one amino acid changes

silent mutation

one base changes, no change in amino acid

nonsense mutation

one base changes, results in early start

differences between DNA of different organsims

order that nitrogen bases appear on the strand, number of base pairs

nucleotide

phosphate, sugar, and base

Watson and Crick

physical models narrow down possibilities

What is protein synthesis?

process of turning DNA into protein

golgi body: role in protein synthesis/ movement of the protein to its final location

processes and packages proteins for delivery to their final location after they have been synthesized

Pauling

proteins take the shape of an alpha helix, use protein for comparison while researching DNA

mRNA: role in protein synthesis/ movement of the protein to its final location

reads DNA, exits nucleus with code

point mutations

replace one base with a different one one amino acid change, early stop of translation or no change at all

ER: role in protein synthesis/ movement of the protein to its final location

since there are many ribosomes (sites of protein synthesis) on the ER, the ER provides a large surface area on which ribosomes can be situated, therefore allowing protein synthesis to occur on a large scale

central dogma of bio

DNA --> RNA --> protein

Avery

DNA carries genetic info, DNA is the gene

What makes RNA different from DNA?

1 strand, ribose, A-U and C-G, no T in RNA

How does transcription happen?

1) enzymes unwind and unzip DNA 2) mRNA reads DNA (enzyme helps bring in nucleotides and bond them together) 3) single strand mRNA exits nucleus with code; DNA zips end winds back to normal

How does translation happen?

1) mRNA code is read 2) tRNA brings in appropriate amino acid 3) translation will stop when it reaches a stop codon

What makes DNA different from RNA?

2 strands, deoxyribose, A-T and C-G

nitrogen base

A, T, C, G

What is transcription?

DNA is changed into mRNA

mutagens: cause of mutations

External things that increase likelihood of mutations occurring, radiation, chemicals (benzene, cyanide, asbestos, etc)

stage one of protein synthesis

transcription

tRNA: role in protein synthesis/ movement of the protein to its final location

transfer RNA, brings in appropriate amino acid, has an anticodon that follows the base pairing rules to match mRNA strand

stage two of protein synthesis

translation

vesicle: role in protein synthesis/ movement of the protein to its final location

transport proteins from golgi

exocytosis: role in protein synthesis/ movement of the protein to its final location

vesicles containing protein use exocytosis to exit the cell membrane

cytoplasm: role in protein synthesis/ movement of the protein to its final location

where translation occurs