DNA chapter 7.3 Flashcards
Genome
all the genetic material in an organisms cells
How is DNA packaged in a eukaryotic cell vs in a prokaryotic cell
The majority of the genome is divided among multiple chromosomes housed inside the cell’s nucleus
In a prokaryotic cell there is only one circular Dna molecule
Chromosome
Is a discrete package of DNA and associated proteins
organelles( eukaryotic) that have DNA and thus their own genomes
- Nucleus
- Mitochondria
- Chloroplast
The well known role of some of DNA
to encode all the cells RNA and proteins/ most of DNA has no known function
gene
a sequence( section) of DNA nucleotides(the building blocks of nucleic acid) that codes for specific protein or RNA molecule.
The human genome consists of how many genes ( each coding for ONE specific protein)
20,000 to 25,000 genes scattered on its 23 pairs of chromosomes
The two steps of protein synthesis
also describes the CENTRAL DOGMA
- Transcription
2. Translation
Transcription
In the Nucleus
a cell copies a gene’s DNA ( the dna stays in the nucleus) sequence to a complementary RNA molecule
Translation
Cytoplasm/ Ribosomes
The information in RNA is used to manufacture a (ONE) protein by joining a specific sequence of amino acids into a polypeptide chain
Recipe /cookbook analogy
- GENE—– RECIPE ( the ingredients and instructions for assembly of one dish) ( likewise a protein encoding gene contains the instructions for assembling a (one) protein, amino acid by amino acid)
- CHROMOSOME——-COOKBOOK ( chromosomes have several arrays of genes ( recipes)
- GENOME—— LIBRARY OF COOKBOOKS
- DNA AND RNA——–Ingredients
2.
Steps to the production of protein ( albumin)
- Inside the nucleus, an enzyme first transcribes the albumin genesDna sequence to a complimentary RNA sequence.
- After some modification , the RNA emerges of the nucleus and binds to a ribosome.
- At the ribosome, amino acids are assembled in a specific order to produce the albumin protein.
the amino acid sequence is dictated by
the sequence of nucleotides in the RNA molecule.
The Rna, in turn was transcribed from the DNA. In this way DNA provides the recipe for every protein the cell.
RNA
An intermediary between DNA and a Polypeptide chain.
. RNA is a multifunctional nucleic acid
DNA vs RNA
RNA DNA
1. sugar (ribose) deoxyribose
1b. 2nd carbon..OH H
2. Uracil base Thymine base
3. adenine-uracil adenine-thy
4. can be single stranded Double
5. can catalyze chemical rx no
The 3 types of RNA
- Messanger RNA (mRNA)
- Ribosomal RNA (rRNA)
- Transfer RNA (tRNA)
Messanger RNA (mRNA)
carries information that specifies a protein. Encodes amino acid sequence.
a group of 3 mRna in a row forms what
A Codon
Codon
a genetic “code word”that corresponds to an amino acid. 3 bases/ 3 nucleotide/ 3 letters that code for a single amino acid.
Ribosomal RNA (rRNA)
Combines with proteins to form RIBOSOMES.
Ribosomes
Are the physical location of protein synthesis
Transfer RNA (tRNA)
They bind an mRNA codon at one end and a specific amino acid at the other.
. Their role is tho carry each amino acid to the ribosome at the correct spot along the mRNA molecule
What is the relationship between a gene and a protein?
A gene is a strand of DNA that encodes a protein
What are the two main stages in protein synthesis?
Transcription and translation are the two main stages in protein synthesis
The genome in prokaryotic vs eukaryotic cells
Prokaryotic: consists of one circular DNA in its nucleoid.
Eukaryotic : the majority is divided among multiple chromosomes housed inside the cells nucleus
What are the three types of RNA, and how does each contribute to protein synthesis
Messenger RNA (mRNA) carries the DNA instructions for building the protein, transfer RNA (tRNA) carries the appropriate amino acid to the ribosome, and ribosomal RNA (rRNA) is the major component of a ribosome, the structure that reads codons on the mRNA and assembles amino acids into polypeptides.
What is central dogma of biology ( Watson and Crick)
States that information stored in DNA is copied to RNA ( transcription), which is used to assemble proteins( translation)
Describes the deduction that each gene somehow controls the production of ONE protein.
Describes the relationship between nucleus acids and proteins as a flow of information called the central dogma.
The proceed if protein production
Where is the instruction stored in a gene?
In the bases. 3 nucleotide, consequently 3 bases hold the information to make one amino acid. Every 3 letters (codon)code for one amino acid.
What does the word Deoxyribonuecleic
Deoxy: refers to what makes a deoxyribose ( the sugar) different from a ribose. The 2nd Carbon of ribose has an OH, but deoxyribose only has an H( it is without an oxygen )
Nucleic: DNA is found in the nucleus of a cell
Acid: phosphates donate hydrogen which makes it acidic.
ATP relationship to RNA.
ATP is modified RNA nucleotide
What reaction link nucleotides together
Dehydration synthesis
All 3 parts of DNA are bonded by
Covalent bonds
What gives DNA it’s helix shape making it stable
Hydrogen bond formed with distant bases.
THE CENTRAL DOGMA
A flow if information between nucleic acids and protein. This describes protein synthesis : Transcription and Translation
How is DNA packaged in a eukaryotic cell
The majority of the genome is divided among multiple chromosomes housed inside the cell’s nucleus
How is DNA packaged in a prokaryotic cell
In a prokaryotic cell there is only one circular Dna molecule
What is a gene bounded by
a PROMOTER AND a TERMINATOR sequence
