Download 浙江万里学院《基因工程》试题（二）参考答案

浙江万里学院《基因工程》试题（二）参考答案
I.
Definition:
1. Auxotroph: A bacterium which can not grow in a minimal medium-that before any
organic substances other than a carbon source was added into me minimal medium.
2. Gene Therapy: A therapy which is using molecular technology to inject foreign genes
into human cells in order to correct genetic defects.
3. Transgenic Animals: Animals which carrying foreign genes.
4. Denaturation: a transition from the native to the denatured state.
5. The process by which RNA molecules are initiated, elongated, and terminated
is called transcription.
6. The excision of the introns and the formation of the final mRNA molecule by
joining of the exons are called RNA splicing.
II.
1.
2.
3.
4.
5.
6.
True or False
True
False
False
True
False
False
III. Fill in with proper words to make the statement complete
1. Nucleic acids - polymers of nucleotides
2. Polysaccharides - polymers of sugars
3. 5‘-GATATGGGTATTGAC-3’
3’-CTATACCCATAACTG-5‘
4. rRNA, tRNA and mRNA.
5. Template.
6. Initiation, elongation, termination
IV.
1.
2.
3.
4.
5.
6.
Multiple choices
b)., c). and d).
c).
a).
a).
c).
b).
V.
Simple questions
1. All DNA molecules have a negative charge and, therefore, move in the same direction
when electrophoresed. This is not true for protein molecules, however, because they may
have a net positive or negative charge.
2. DNA Template; Primer; dNTP (dATP, dCTP, dGTP, dTTP); DNA polymerase; and
Dideoxyribonucleotide – reaction terminator
3. a). Restricting free passage of most intra- and extra-cellular substances; b). Allowing
transport of specific substances by molecular pumps 泵, channels 通道, and gates
4. The activation of the phosphate group so that it will combine with another nucleotide at a
reasonable speed. The protection of reactive groups on the nucleotide to prevent
unwanted side reactions
5. lock-and-key and induced-fit models
6. Stable; Be able to express when needed; Replication from cell to cell; Transmitted from
parent to progeny
VI.
Comprehensive questions:
1. 1). Prokaryotes initiate translation at an AUG codon just downstream of the
Shine-Dalgamo sequence (ribosome-binding site) AGGAGGU, which base-pairs
with a section of the 16S rRNA near its 3' end. The eukaryotic ribosomal
small
subunit binds at the 5' cap of mRNA, and the first AUG encountered is used.
2). Prokaryotes initiate translation with formylmethionine, whereas
eukaryotes initiate with an unmodified methionine.
3). Prokaryotic mRNAs may be polycistronic, since the ribosome may
reinitiate translation at a second AUG following termination of translation of the first
reading frame. Eukaryotic ribosomes do not reinitiate translation without first
dissociating
2.
polymerizing activity,
5' -3' exonuclease,
3'-5' exonuclease.