unit 9 Flashcards
What is the role of DNA in heredity?
-Storing genetic information
-Copying genetic information
-Transmitting the genetic information
What are nucleotides made up of?
-5-carbon sugar called deoxyribose
-Phosphate group
-Nitrogenous base
What are the 4 nitrogenous bases in DNA?
Thymine, Adenine, Cytosine, Guanine
What is the macromolecule in DNA?
Nucleic acid
What is the polymer in DNA?
DNA
What is the monomer in DNA?
Nucleotide
What direction do the strands in DNA run?
In opposite directions, they are antiparallel
What are the nucleotides held together by?
Covalent bonds in the backbone
What are the two strands of DNA held together by?
Hydrogen bonds between the nitrogenous bases
What are the base pairings?
A and T = 2 hydrogen bonds
G and C = 3 hydrogen bonds
Which bonds are the strongest?
Covalent bonds
What is the purpose of DNA replication?
New copy of DNA for every cell
What does DNA being semiconservative mean?
1 parent strand and 1 new strand
What is helicase?
The “unzipper”; breaks hydrogen bonds between strands
What is primase?
The “initializer”; makes RNA primer
What is polymerse?
The “builder”; adds nucleotides to the new strand 5’ and 3’
What is ligase?
The “gluer”; create covalent bonds between nucleotides to connect fragments
What are the differences between DNA and RNA?
DNA: Deoxyribose sugar, 2 strand, A = T G = C, stores
RNA: Ribose sugar, 1 strand, A = U G = C, transfers
What is the role of DNA?
Stores information and genetic material
What are proteins made of?
Monomer- Amino acids
What is the role of proteins?
Muscles, transport, stores, enzymes, structural
What do the genes in DNA contain?
Information to make proteins
What is transcription?
Where the cell makes mRNA copies of genes that are needed
Occurs in the nucleus of eukaryotes
What is translation?
Where the mRNA is read by the ribosomes to make proteins
Occurs in the cytosol
What is a gene?
Unit of DNA that carries information to make a proteins
What is mRNA?
Messenger RNA, it carries information from a gene in DNA
What is RNAP
RNA polymerase, the enzyme that reads DNA to make mRNA (5’-3’)
What is the first step of transcription?
RNA polymerase binds to the template strand of DNA at the beginning of a gene called the promoter
What is the second step of transcription?
RNA polymerase moves along the gene unwinding the DNA and creating a complementary strand of RNA stopping when it reaches the terminator. Using the RNA base pairing rules
What is the RNA base pairing rules?
G-C and A-U
What is the initial mRNA that is produced called?
The primary transcript
How does mRNA become mature?
It must go through processing
What are exons?
Coding regions (expressed)
What are introns?
Non-coding regions (interrupting)
Must be removed before primary transcript is mature and can leave nucleus