BSC 1010C Exam 4 Questions With Complete Solutions
. What useable product do you end up with at the end of PCR?
Correct Answers a. Clones of a specific segment of DNA
· Biotechnology - Correct Answers the manipulation of
organisms or their components to make useful products
· DNA cloning - Correct Answers the process by which
scientists prepare well-defined DNA segments in multiple
identical copies
· lac operon - Correct Answers an inducible operon that codes
for enzymes used in the hydrolysis and metabolism of lactose
into glucose and galactose
· proteasomes - Correct Answers protein complexes which
degrade unwanted or damaged proteins
· trp operon - Correct Answers the operon that codes for
enzymes used in the building of tryptophan; When tryptophan
levels are high, it binds to the trp repressor protein, serving as a
corepressor and turning the operon off
· ubiquitin - Correct Answers the protein used to mark other
proteins for degradation
1. Compare and contrast transcription in prokaryotes and
eukaryotes. Correct Answers a. The process is very similar
between the two, however...
,b. Transcription in prokaryotes - there is no further modification
of the transcript after it has been made and it can be immediately
translated
c. Transcription in eukaryotes - the primary transcript is
modified into mRNA by RNA splicing and the addition of the 5'
cap and the poly-A tail.
1. Describe histone acetylation. Correct Answers a. In histone
acetylation, acetyl groups are attached to an amino acid in a
histone tail which promotes transcription by opening up the
chromatin structure
1. Describe how an inducible operon is different than a
repressible operon. Correct Answers a. Inducible operons are
usually off but can be turned on; repressible operons are usually
on, but can be turned off
1. Describe how mutations lead to changes in gene regulation,
which lead to cancer. Correct Answers a. At the DNA level, a
cancerous cell is usually has at least one active oncogene and
several mutated of tumor-suppressor genes; these genes
normally control cell life span and cell cycle; after mutation the
cell may exhibited extended life span (allowing it to accumulate
additional mutations) and/or an out of control cell cycle (causing
it to divide rapidly and continuously leading to tumor
formation); it takes mutation to several of theses genes to
generate malignant cancer
1. Describe the characteristics of the different amino acids.
Correct Answers a. Glycine, alanine, valine, leucine, isoleucine,
, methionine, phenylalanine, tryptophan, and proline are non-
polar and can have non-polar interactions, but repel water
b. Serine, threonine, cysteine, tyrosine, asparagine, and
glutamine are polar and can form hydrogen bonds
c. Aspartic acid and glutamic acid are acids, but lysine, arginine,
and histidine are bases. The acids and bases can form ionic
bonds
1. Describe the difference between embryonic stem cells and
adult stem cells. Correct Answers a. Embryonic stem cells can
differentiate into any type of cell whereas adult stem cells can
only differentiate into a select few cells (fat, bone, blood)
1. Describe the general life cycle of a virus.
. Correct Answers a. The virus enters the host cell and the
nucleic acid and capsids separate. Once a viral genome has
entered a cell, the cell begins to manufacture viral proteins,
using host enzymes, ribosomes, tRNAs, amino acids, ATP, etc.
The nucleic acid is replicated to produce copies of the viral
genome and transcribed/translated to produce more capsomeres.
These products self-assemble into new virus particles which
then exit the cell
1. Describe the process by which enhancers and activators
encourage gene expression. Correct Answers a. An activator
protein binds to an enhancer to help initiation of gene
transcription; Bound activators come into contact with mediator
(helper) proteins through protein-mediated bending of the DNA;
The mediator proteins help assemble and position the
transcription complex
. What useable product do you end up with at the end of PCR?
Correct Answers a. Clones of a specific segment of DNA
· Biotechnology - Correct Answers the manipulation of
organisms or their components to make useful products
· DNA cloning - Correct Answers the process by which
scientists prepare well-defined DNA segments in multiple
identical copies
· lac operon - Correct Answers an inducible operon that codes
for enzymes used in the hydrolysis and metabolism of lactose
into glucose and galactose
· proteasomes - Correct Answers protein complexes which
degrade unwanted or damaged proteins
· trp operon - Correct Answers the operon that codes for
enzymes used in the building of tryptophan; When tryptophan
levels are high, it binds to the trp repressor protein, serving as a
corepressor and turning the operon off
· ubiquitin - Correct Answers the protein used to mark other
proteins for degradation
1. Compare and contrast transcription in prokaryotes and
eukaryotes. Correct Answers a. The process is very similar
between the two, however...
,b. Transcription in prokaryotes - there is no further modification
of the transcript after it has been made and it can be immediately
translated
c. Transcription in eukaryotes - the primary transcript is
modified into mRNA by RNA splicing and the addition of the 5'
cap and the poly-A tail.
1. Describe histone acetylation. Correct Answers a. In histone
acetylation, acetyl groups are attached to an amino acid in a
histone tail which promotes transcription by opening up the
chromatin structure
1. Describe how an inducible operon is different than a
repressible operon. Correct Answers a. Inducible operons are
usually off but can be turned on; repressible operons are usually
on, but can be turned off
1. Describe how mutations lead to changes in gene regulation,
which lead to cancer. Correct Answers a. At the DNA level, a
cancerous cell is usually has at least one active oncogene and
several mutated of tumor-suppressor genes; these genes
normally control cell life span and cell cycle; after mutation the
cell may exhibited extended life span (allowing it to accumulate
additional mutations) and/or an out of control cell cycle (causing
it to divide rapidly and continuously leading to tumor
formation); it takes mutation to several of theses genes to
generate malignant cancer
1. Describe the characteristics of the different amino acids.
Correct Answers a. Glycine, alanine, valine, leucine, isoleucine,
, methionine, phenylalanine, tryptophan, and proline are non-
polar and can have non-polar interactions, but repel water
b. Serine, threonine, cysteine, tyrosine, asparagine, and
glutamine are polar and can form hydrogen bonds
c. Aspartic acid and glutamic acid are acids, but lysine, arginine,
and histidine are bases. The acids and bases can form ionic
bonds
1. Describe the difference between embryonic stem cells and
adult stem cells. Correct Answers a. Embryonic stem cells can
differentiate into any type of cell whereas adult stem cells can
only differentiate into a select few cells (fat, bone, blood)
1. Describe the general life cycle of a virus.
. Correct Answers a. The virus enters the host cell and the
nucleic acid and capsids separate. Once a viral genome has
entered a cell, the cell begins to manufacture viral proteins,
using host enzymes, ribosomes, tRNAs, amino acids, ATP, etc.
The nucleic acid is replicated to produce copies of the viral
genome and transcribed/translated to produce more capsomeres.
These products self-assemble into new virus particles which
then exit the cell
1. Describe the process by which enhancers and activators
encourage gene expression. Correct Answers a. An activator
protein binds to an enhancer to help initiation of gene
transcription; Bound activators come into contact with mediator
(helper) proteins through protein-mediated bending of the DNA;
The mediator proteins help assemble and position the
transcription complex
