LAB #6: THE GENETIC MATERIAL Flashcards
What are Nucleic acids?
chemicals found in cells; they are composed of carbon, hydrogen, nitrogen, oxygen, and phosphorus. They serve as information chemicals in cells.
What’s Deoxyribonucleic acid (DNA)?
Its one of the nucleic acids, that has been called “the blueprint of life.”
It is a chemical found in all life forms, & contains the cell’s instructions for the production of proteins.
What are Genes?
Sections of DNA that code for the production of proteins.
What is DNA?
Genetic make-up for all organisms
Where is DNA found?
In the Nucleus (“a sort of command center”)
Whats Ribonucleic Acid (RNA)?
Its DNA chemical cousin;
It acts as a “middleman”in the protein construction process ,which happens outside the cell’s nucleus in the CYTOPLASM!
What is transcription?
where the information from DNA is “rewritten” to form a kind of RNA called MESSENGER RNA (mRNA).
What is mRNA?
it’s a chemical message telling the cell which protein subunits must be assembled in what order to produce a protein.
The mRNA leaves the nucleus to go to the site of protein construction && the DNA stays behind in the nucleus.
What is transfer RNA (tRNA)?
Occurring in the cytoplasm of the cell, special RNA’s pick up the subunits of proteins, amino acids.
20 diferent amino acids, each unique tRNA
Ribosomes are:
“protein factory”….
read coded message for protein construction carried by the mRNA in the process called TRASLATION, & they make sure proper amino acids are assembled in the correct sequence.
What is a polypeptide?
A completed amino acid chain which is assembled together to build functional proteins.
What is a Nucleotide?
(Nucleic acids are constructed from theses subunits)
It contains 3 parts: a phosphate group, a five-carbon sugar, & a nitrogen-containing base.
DNA nucleotides have how any types of nitrogenous bases?
4
(2 of them have a single ring C & T)
(Other 2 have a double ring: A & G)
How do RNA nucleotides differ from DNA nucleotides?
the sugar is different (the sugar is deoxyribose in DNA, whereas the sugar is ribose in RNA)
plus RNA nucleotides don’t have thymine as a base!!! RNA has uracil U!!!
Individual nucleotides are connected together to make what?
Polynucleotide strand, that has a backbone where the phosphate groups and sugars alternate. The nitrogenous bases are connected to the sugars.
RNA’s consists of only one strand of?
Nucleotides
Pyrimidines (single-ring bases)
Cytosine, Thymine, & Uracil (RNA)
Purines (double-ring bases)
Adenine & Guanine
What is a double helix?
The 3-D structure of DNA, where 2 spirals twist around each other like a twisted rope ladder.
What are complementary bases?
A certain nitrogenous base in DNA that will bond to certain others. A goes with T, G goes with C
DNA copying is called?
REPLICATION
Double Helix Structure:
(IN A NUCLEOTIDE)
Bases=in center
Sugars= Pentagon darker/Backbone
Phosphate=white circles/backbone
In most human cells DNA make up how many chromosomes?
46
Actively dividing somatic cells have a cell cycle that is comprised of?
mitotic phases and an interphase (which are continuous processes)
A cell that shows a clearly defined nucleus with chromatin granules (DNA) is a cell in what?
INTERPHASE
Interphase is
a time of cellular activity between cell divisions
It is the longest phase of the cell cycle!!!!
What is Nucleoi?
A spherical structure located within the nucleus
It’s involved in making the ribosomes of the cell.
What is the centromere?
Where the chromatids of each original chromosome are uncoiled in the S sub-phase but are attached to each other at a region of the DNA
What’s the purpose of Mitosis?
To provide copies of DNA for daughter cells during cell reproduction.
(prophase, metaphase, anaphase, and telophase/cytokinesis)
What is cytokinesis?
The division of the cytoplasm
What does Mitosis end with?
Telophase and cytokinesis where there will be 2 cells formed and each one will have a copy of the DNA from the parent cell.
This DNA is identical: both daughter cells will have the same genes!
What are Genes?
genetic codes for the production of polypeptides which are then used to construct proteins.
Chromosomes contain _________ && ________contains genes.
DNA
What are Variable Number Tandem Repeats (VNTRs)?
introns composed of repeating DNA
These vary in people (identical twins have same exact DNA)
What has DNA fingerprinting been used for?
Paternity suites and criminal cases
Whats Restriction fragment length polymorphism (RFLP)?
commonly called DNA fingerprinting; Where DNA is isolated from a cell, then cut into fragments using special chemicals, then these variable length fragments can be separated by size.
When a person has a lot of repeats in their introns, the sizes of their DNA framents will be
LONGER
Electrophoresis?
Where individual fragments are separated through this process
The DNA sample is placed near the edge of a gel which is placed in an electrical field.
LARGER FRAGMENTS MOVE MORE SLOWLY THROUGH GEL
DNA is ________Charged?
Negatively
___________ fragments move further down in electrophoresis?
SHORTER
