5 Written questions
5 Matching questions
- Reading frame
- Mechanisms controlling transcription
- a Grouping of a stretch of nucleotides into sequential triplets; an mRNA molecule has 3 reading frames, but only 1 is typically used in translation.
- b Ribosomal RNA -> type of RNA molecule present in ribosomes. rRNA builds the ribosomes
- c Messenger RNA -> type of RNA molecule that is translated during protein synthesis.
- d 1) Often controlled by regulatory region near promoter ->Protein binds to region and acts as "on/off" switch -> Binding protein can act as repressor or activator -> Repressor blocks transcription and Activator facilitates transcription 2) Set of genes controlled by protein is called an operon
- e Cytosine
5 Multiple choice questions
- 1) RNA is made up of nucleotides -> Ribonucleotides 2) RNA contains nitrogenous bases -> Adenine, Guanine, Cytosine, Uracil (Uracil replaces thymine in RNA) 3) RNA usually exists as single stranded molecule 4) Portion of DNA acts of template for RNA synthesis -> Either strand of DNA can act as template 5) Three different functional groups of RNA mRNA, rRNA, tRNA
- Study of sequence of DNA
- 1) Control mechanism that inhibits gene expression and decreases the synthesis of enzymes 2) Repression is usually in response to the overabundance of an end product 2.1) Repression decreases the rate synthesis of enzymes leading to the formation of the particular end product 2.2) Regulatory proteins called repressors mediate repression -> Repressors block the ability of RNA polymerase to bind and initiate protein synthesis
- DNA molecule is antiparallel -> Strands are oriented in opposite directions, strands differ at the ends 1) One strand oriented in the 5' to 3' direction. 2) The other strand is oriented in the 3' to 5' direction.
5 True/False questions
Transcript → Process of synthesizing RNA from DNA template 1) mRNA carries the coded information from DNA to the ribosome, which is the site of protein synthesis 2) mRNA also plays an important role in translation 3) During transcription the enzyme, RNA polymerase, synthesizes a complementary strand of mRNA from a portion of unwound DNA
Phase variation → Routine switching on and off of certain genes -> Altering expression allows portions of population to survive and multiply
3' refers to → 3'OH -> 1 strand of the DNA has a hydroxyl group attached to the number 3 carbon of the sugar. -> Termed the three prime (3') end
RNA polymerase → Enzyme that synthesizes RNA using single stranded DNA as a template; synthesis always occur in the 5' to 3' direction.
Inducible enzymes → 1) Routinely synthesized 2) Generally involved in biosynthesis