Question

ANSWER THE FOLLOWING QUESTIONS 1) What is the relationship between a gene and a protein? 2) How does the tRNA contribute to protein synthesis? 3) The ability of cell to control their gene expression is called 4) What is a promoter? 5) What process convert the message from mRNA into amino acids? 6) The following expressions are true or false? Explain a. "A gene is any DNA sequence that is transcribed to any type of RNA b. "In eukaryotes, a mRNA molecule can only be translated by one ribosome at a time "Mutations cause incorrect sequencing of nucleic acids. Incorrect sequencing of DNA will result in new alleles, and it may lead to evolution. Incorrect sequencing of mRNA will result in a faulty protein, but it will not lead to evolution 7) Name 3 factors that can affect gene expression 8) Make your own using the following terms make your own concept map of protein synthesis: a) DNA b) RNA c) mRNA, RNA, RNA d) ribosomes e) cytoplasm f) codon El protein h) amino acids 0 transgenic organisms

Answer 1

1. Gene is transcribed into an mRNA by the RNA polymerase and this mRNA is then translated to polypeptide or protein by a ribosome.

2.During protein synthesis, tRNA is activated and then carries the respective amino acids to the ribosome where the amino acids are joined to polypeptide.

3. The ability of cell to control their gene expression is called gene regulation.

4.Promoters are sequences in DNA that define where the transcription of a gene by RNA polymerase begins.

5. The process that converts the message from mRNA into amino acids is called translation.

6. a. True. A gene is a fundamental unit of chromosome which codes for a protein and controls a trait or more than trait.

b. False. Multiple ribosomes can transcribe a single mRNA provided that they attach to the first codon. Another evidence for this is the existence of polysomes.

7. 3 factors that affect gene expression :

a. DNA methylation

b. Post-transcriptional gene regulation.

c. Histone modification.