Gel electrophoresis

Gel electrophorosis

Where is DNA found in a eukaryotic cell?

In the nucleus (also small amounts in mitochondria).

What structure in the nucleus contains DNA?

Chromosomes

what are chromosomes

a piece of DNA

What is the shape of DNA called?

double helix.

What does the DNA double helix look like?

two polynucleotides that are twisted hecically around each other- resembles a ladder

What forms the sides of the DNA “ladder”?

Sugar and phosphate molecules.

What forms the rungs of the DNA “ladder”?

Nitrogen bases.

What is a nucleotide?

a subunit of a nucleic acid (they are the building blocks of DNA)

how many chromosomes do humans have

46 in total, 23 from your mum, 23 from your dad

what are the three parts that make up a nucleotide

sugar with a deoxyribose base, phosphate group, and a nitrogen base

what are the four nitrogen bases in DNA

Adenine, thymine, cytosine, guanine,

what is the base pairing rule

Adenine pairs with thymine, cytosine pairs with guanine

why is the base pair rule important

it ensures accurate DNA replication

what is a polynucleotide chain

when nucleotides join together by their sugar and phosphate groups to form a long chain

why are the hydrogen bonds weak

so they can be broken so the stand can be unwound and coppied

what are DNA two vital properties

making copies of itself, and carry information the oder of bases along a strand is a code fro making protiens

what are chromosomes made up of

DNA molecules tightly wound around proteins

what are genes

a DNA sequence based of nucleotide base pairs that form all your traits

where are genes located

along eacg length of a chromosome, in a specific position

what does mRNA stand for

messanger RNA

where is mRNA found

made in the nucleus and moves to the cytoplasm

wht is the role of mRNA

it carries the genetic instuctions from DNA to the robosomes

how do genes make protein

the DNA molecule unwinds and one stranct as a patterns to form a molecule of mRNA which then coppies the code

what does tRNA stand for

transfer RNA

where is tRNA found

in the cytoplasm

what is the role of tRNA

brings amino acids to the ribosome during protien synthesis

what does RNA consist of

ribose sugar, a nitrogen base - adenine, cytosine, guanine, uracil

what is an allele

a different version of the same gene

what is transcription

the process where DNA is coppied into mRNA

where does transcription occur

in the nucleus

what is translation

the process where mRNA is used to build a protien

where does translation occur

at the bibsome in the cytoplasm

what is a codon

a sequence of three bases on mRNA that codes for one amino acid (mRNA)

what is an anticodon

a complementy sequence of three bases on tRNA

what is the process of transcription

the DNA is unzipped unwinding into two stands, an enzyme called RNA polymerase moves along the exposed gene on the DNA strad, as it goes it joins together RNA nucleotides which from a stand of mRNA, the nucleotides are complementry to the DNA nucleotodes. the RNA plymerase detaches once the mRNA strand it complete the two DNA stands then rejoin.

what is the process of translation

the mRNA leaves the necleus and attach to a ribosome in the cytoplasm, it then tells the ribosome the order to connect the amino acids that will make up a protein, the nitrogen bases are read in groups of three called codons, each codon corresponds to a signle amino acid, the amino acids are bought to the ribosome by tRNA, the amino acid joins in a chain according to the order specified by the sequence of codons in mRNA. they then form a long chain which becomes the final protien.

how do codons and anticodons work together

The anticodon on tRNA matches the codon on mRNA to add the correct amino acid.

What is the role of the ribosome?

It reads mRNA and links amino acids together to form proteins.

What is gel electrophoresis?

A technique used to separate DNA fragments by size.

What determines how far DNA travels in the gel?

The size of the DNA fragments.

Which DNA fragments move further in the gel?

Smaller fragments.

What do bands represent in a gel?

DNA fragments of the same size

What does a thicker/darker band mean?

More DNA fragments of that size.

If two samples have bands at the same position, what does that mean?

They contain DNA fragments of the same size

Why might scientists compare DNA band patterns?

To identify individuals or compare DNA samples.

What is a DNA ladder?

A reference with DNA fragments of known sizes

Why is a DNA ladder used?

To estimate the size of DNA fragments in samples

how does the process of electrophorosis work?

separates molecules like DNA based on size and charge by forcing them through a porous gel (like agarose) using an electric current. Negatively charged molecules migrate towards a positive electrode , with smaller molecules moving faster and farther through the gel sieve than larger ones

what are the requirments for gel electrophoresis

A DNA, RNA or protien samples, a DNA ladder with know fragments, a matchine with a current and wells, and agarose gel