Central Dogma Flashcards by Sydney Hoag

Basic postulates of the central dogma

DNA—-> RNA—–> protein

How well did you know this?

Not at all

Perfectly

Process of making protein based on specific DNA sequence is much more __________ than central dogma states

Complicated

How well did you know this?

Not at all

Perfectly

Purpose, location, and direction of transcription

Converting the DNA sequence of a gene into messenger RNA

Occurs in the nucleus

mRNA transcribed in the 5’-3’ direction

How well did you know this?

Not at all

Perfectly

Direction the template of DNA strand is read for transcription

still read in the 3’-5’ direction

How well did you know this?

Not at all

Perfectly

Define gene

A sequence of DNA from which a specific protein is derived

How well did you know this?

Not at all

Perfectly

Average length of a human gene in base pairs and kilo base pairs

10,000-15,000 base pairs long

10-15 kilo base pairs long

How well did you know this?

Not at all

Perfectly

2 components of a gene

Exons and introns

How well did you know this?

Not at all

Perfectly

Exons definition

Sequence that codes for amino acids

How well did you know this?

Not at all

Perfectly

Introns definition

Noncoding segments

How well did you know this?

Not at all

Perfectly

The _____ and ______ of exons and introns varies greatly in the genome

Length and number

How well did you know this?

Not at all

Perfectly

Describe what the terms upstream and downstream mean

Upstream means located in front of the gene (within 100 bp)

Downstream means located behind the gene

How well did you know this?

Not at all

Perfectly

Describe location of a promoter

Upstream of gene (within 100 bp)

Possibly multiple promoters at different sites for a gene

How well did you know this?

Not at all

Perfectly

Identify bp most commonly found in a promoter

Many Ts and As (TATA box)

How well did you know this?

Not at all

Perfectly

The number of promoters ________ and this is used in __________________

Varies. This is used in tissue regulation

How well did you know this?

Not at all

Perfectly

Function of a promoter

Transcription starts here

How well did you know this?

Not at all

Perfectly

Location of enhancers

Regulatory sequences on both sides of a gene (1000s of bp away)

How well did you know this?

Not at all

Perfectly

Distance enhancer can be from gene

1000s of bp away from gene

How well did you know this?

Not at all

Perfectly

Function of transcription factors

They are DNA binding proteins used for gene regulation

How well did you know this?

Not at all

Perfectly

Explain what is meant by repressor or activator transcription factor

It either activates gene regulation or represses gene regulation

How well did you know this?

Not at all

Perfectly

Define ligand

Ion or molecule

How well did you know this?

Not at all

Perfectly

Explain how transcription factors are activated

Activated by specific ligand or by corepressor or coactivator proteins

How well did you know this?

Not at all

Perfectly

State where in the cell transcription factors may be found

In cytosol or nucleus

How well did you know this?

Not at all

Perfectly

State where in the cell transcription factors have to be to perform their function

Once activated, will move into nucleus

How well did you know this?

Not at all

Perfectly

5 main functions of proteins

Enzymes, transporters, receptors, antigens, and transcription factors

How well did you know this?

Not at all

Perfectly

Describe 5 main functions of proteins

Enzymes-increase reactions Transporters- pass material through membrane Receptors- change cellular activity, allow certain reactions. The "on" switch for neuronal reactions Antigens- allows cellular identity Transcription factors- turn on or off gene expression

Identify the first enzyme needed for transcription to begin

Binding of RNA Polymerase to promoter

3 types of RNA poly and what each type makes

I- rRNA transcription (makes ribosomes) II- mRNA transcription (code) III- tRNA transcription (helps with translation)

State the direction RNA poly travels down the template, and the direction the new strand of RNA is being made

Poly reads DNA and copies RNA strand from 5'-3'

________ takes the place of thymine in DNA

Uracil

Identify the "cap" added to the 5' end of the mRNA

7-methylguanine

Identify the code at the 3' end of housekeeping gene

AAUAAA

Identify what is added to the 3' end of housekeeping genes

Addition of 100-200 A's (the poly A tail)

Explain why these two structures are added to mRNA

It's used for stability and support to cytoplasm

Identify the location of the splicing mRNA

Occurs in the nucleus

Identify the splice donor and the splice acceptor and where they're found in mRNA

5' end of all introns start with GU (splice donor) | 3' end of all introns end with AG (splice acceptor)

State the number of bases usually found in small nuclear RNA, and what transcribes it

Less than 200 bp. Transcribed by RNA Poly II

Explain how alternative splicing affects gene expression

Some exons may be included in the splice, resulting in a different protein being translated

Explain how splicing can be used as a method of evolution and speciation

Can produce many proteins from same gene-greater protein diversity

Describe the two subunits that make up a ribosome

60S and 40S. Each subunit is comprised of proteins and RNA

Translation purpose

Producing protein from mRNA strand

How do you make protein from mRNA strand

Linking individual amino acids in polypeptide chain

Where does translation occur

In cytoplasm

What's the translation organelle

The ribosome

Identify the role amino acids play in the formation of a protein

They are the building blocks of protein

Write the correct formula for amino acid

``` O H || | H-O-C-C-NH2 | R ```

Explain the role of the functional group in an amino acid and protein

Gives the protein it's chemical characteristics, is different for different amino acids, and gives the protein it's shape

Identify the two terminal ends of an amino acid and what their names are

?????

Define codon

mRNA is read in groups of 3 nucleotides, called codons

Explain how codons, found on RNA, relate to a specific amino acid, found on tRNA

mRNA is read in a group of 3 nucleotides, called codons. Each codon encodes for a specific amino acid

Identify the start codon, and what it codes for

It's always AUG, and it encodes for methionine

Explain how it is determined that a polypeptide is done translating

Translation continues until a stop codon is read (UAA, UAG, or UGA)

Scientist who explained the code in the codons, and what year

FJ Taylor in 1989

Explain the code in the codons

The first nucleotide tells what precursor the amino acid is made from. The 2nd nucleotide tells the polarity of amino acid. The third nucleotide has no specific function but has the greatest diversity

Summarize the role of each RNA used in translation

mRNA: holds code for structure of protein tRNA: have anticodons, and bind specific amino acids rRNA: part of ribosome

List the three phases of translation

Initiation, elongation, and termination

Describe what happens in initiation

Binding tRNA anticodon UAC with the start codon AUG

Describe what happens in elongation

Uses elongation factors, and ATP and GTP Ribosome binds to 2 codons (tRNA enters A site and binds to mRNA, peptide bond forms between amino acid in P site with new one in A site. P site a.a is released. Ribosome moves down mRNA then empty tRNA is released and new mRNA codon is in A site)

Describe what happens in termination

Stop codon is reached, OH is added to end of peptide, and is released by release factors

List the three sites found in a ribosome that are used for translation

A site, P site, E site

Summarize the role each site plays in translation.

tRNA enters A site and binds to mRNA. Peptide bond forms between amino acid in P site with new one in A site. P site a.a. is released Ribosome moves down mRNA towards 3' end and Empty tRNA is released, and new mRNA codon is in A site. Process repeats