Ch. 6: Activity
What occurs during RNA processing?
1. A modified guanine nucleotide is added to the beginning of the RNA strand as a cap. 2. Segments of the RNA strand that do not actually code for the protein are removed. 3. Segments of the RNA that do code for the protein are reconnected. 4. Adenine nucleotides are added tot eh end of the RNA strand, forming a tail.
Why does a gene NOT constantly churn out the same protein at all times in every cell?
1. mRNA processing can allow one gene to produce several different proteins. 2. Genes are constantly being turned on and off through the process of gene regulation.
What percent of human genome encodes for proteins
1.5%
What is an example of a transgenic organism?
A bacterium with human gene for producing insulin
If you wanted to visualize the location of a particular gene on a particular chromosome, you might use
A fluorescent nucleotide probe.
How many kinds of DNA nucleotides are there?
A, T, C, G
Where does translation occur?
At the ribosomes in the cell cytoplasm
A ______ is a lump of abnormal cells that, although growing out of control, remains at its original site.
Benign tumor
An individual with a malignant tumor is said to have
Cancer
______ provides directions for its own replication. It also directs cell activities by providing instruction for building proteins
DNA
The key process for information storage and transfer to offspring cells is_______
DNA replication
The central dogma follows the flow of information from
DNA to protein
What are the differences between DNA and RNA?
DNA: AGCT, double stranded, and deoxyribose RNA: AGCU, single stranded, and ribose
The structure of DNA is a ______, held together by the complementary base-pairing of cytosine with guanine, and adenine with thymine.
Double-helix
What does a nonsense mutation do?
It changes an amino acid codon to a stop codon which can result in the production of a shorter protein product. Almost always defective.
A ______ is an abnormally growing mass of cells that is actively spreading through the body
Malignant tumor
______ is the spread of cancer cells from their site of origin to other sites in the body.
Metastasis
What does mRNA do?
Moves from the nucleus to the cytoplasm following RNA processing.
Nucleic acids are polymers of
Nucleotides
During DNA replication, each of the two daughter DNA molecules contains one strand from the _____ DNA molecule and one _____ strand.
Original Newly synthesized
______ is used to copy just a relatively small region of DNA, not the entire genome.
PCR
A supplemental appendix is to a book as a _____ is to a bacterial chromosome
Plasmid
RNA usually consists of a single ______ strand.
Polynucleotide
_____ set endpoints for the region of DNA that is copied through PCR procedure.
Primers
A gene provides the directions to build a molecule of _____; the genetic instructions it carries are then translated into the amino acid sequence of a protein
RNA
What happens during transcription?
RNA nucleotides line up with their complementary DNA partners, transcribing the information in DNA into RNA.
______ cut DNA at specific nucleotide sequences
Restriction enzymes
What are involved in translation?
Ribosomes, Anticodon, tRNA, and Amino Acids.
How is DNA replication described?
Semi-conservative
What mutation is the LEAST likely to result in harmful changes to cells?
Silent mutations
Gel electrophoresis separates pieces of DNA based on
Size
Which part of DNA nucleotides are always the same? Which part changes?
Sugar and Phosphate groups Base
A polynucleotide has a repeating _____ backbone.
Sugar-phosphate
The process of accurately amplifying a sample of DNA is called
The polymerase chain reaction
tRNA molecules work to
Translate mRNA to produce a specific amino acid sequence.
T or F. MicroRNA molecules can bind to mRNA transcripts, preventing them form producing proteins.
True
The monomers of nucleic acids consists of what three parts
phosphate group, a five-carbon sugar, and a nitrogenous base.