Chapter 5 Power Points Flashcards
(38 cards)
Name the components of DNA
Single phosphate group, a sugar and nitrogen containing base
What does DNA stand for
Deoxyribonucleic acid
Base pairs in DNA
Adenine, thymine, guanine and cytosine
The double helix represents
DNA
A molecule that stores information
Nucleic acid
Sections of DNA that contain instructions for making proteins
Genes
An organisms complete set of DNA
Genomes
One or more unique pieces of DNA
Chromosomes
A sequence of base pairs in a DNA molecule that carries the information necessary for producing a functional product usually a protein molecule or RNA
Genes
Describe alleles
Alternate versions of a gene that code for the same trait
DNA occurs how in prokaryotes
Circular pieces
DNA occurs how in eukaryotes
Linear strands of DNA called chromosomes
Percentage of coding DNA in humans
2%
Introns
Noncoding region of DNA, and may take the form of short and long sequences that are repeated thousands of times they may also consist of gene fragments duplicate versions of genes a psedogene
Genotype
All of the genes contained in an organism
Phenotype
The physical manifestation of the instructions
How does a gene effect a flowers color
Two steps transcription, in which a copy of the genes base sequence is made; and translation in which that copy is used to direct the production of a protein
When does transcription occur in eukaryotes
The nucleus
What happens during transcription
The gene based sequence or code is copied into a molecule called mRNA
What happens during translation
The mRNA move out of the nucleus and into the cytoplasm to the cell where the message encoded in the mRNA molecules are used to build proteins
What are the stages of transcription
1: Recognize and bind- once RMA polymerase recognizes a promoter site it binds to one strand of DNA and begins reading the gene message.
2: transcribe- as the DNA strand is processed through the RNA polymerase, the RNA polymerase builds a single strand copy of the gene, called the mRNA transcript.
3: terminate- when the pRMA encounter a code signaling the end of the gene, it stops transcription and releases the mRNA transcript.
4: copping and editing- a cap and tail are often added for protection and to promote recognition and noncoding sections are removed.
What must be present in the cytoplasm for translation to occur
Free amino acids, ribosomal units and transfer RNA
What is transfer RNA
Transfer RNA molecules translate mRNA code, linking specific bases on the mRNA with specific amino acids, that will be used to build a protein.
A tool used to monitor the expression levels of thousands of genes simultaneously
Microarrays