ppt for lac operon

3. “ Education Through Self-help is Our Motto-: Karmaveer ”
Represented By
Mr. Vaibhav Kisan Phadtare.
Roll No.: 630
T.Y.B.Sc Zoology

4.  All the genes of an operon are co-ordinately
controlled by a mechanism 1st described in 1961 in
Pasture Institue of Paris.
 Operon is operating units which can be defined as the
cluster of genes located together on the chromosomes and
transcribed together.
 It is group of closely linked structure genes and associated
control gene which regulate metabolic activity.

5.  The lactose operon designated as lac operon.
 The lac operon codes for enzymes involved in
catabolism (degradation) of lactose.
 It is inducible operon since the presence of lactose
induce the operon to switched on.
 Lactose is the disaccharide which is made up of
glucose and galactose.

7.  Lactose (-)
 Lactose (+)
 Lactose (+) and Glucose(+)
 Lactose (+) and Glucose(-)

8. Carbohydrates Activator
protein
Repressor
protein
RNA
polymerase
Lac operon
+ Glucose
+ Lactose
Not bound to
DNA
Lifted off
operator site
Keeps falling
off promoter
site
No
transcription
+ Glucose
- Lactose
Not bound to
DNA
Bound to
operator site
Blocked by the
repressor
No
transcription
- Glucose
-Lactose
Bound to DNA Blocked by the
repressor
Blocked by the
repressor
No
transcription
- Glucose
+ Lactose
Bound to DNA Sits on the
promoter site
Sits on the
promoter site
Transcription

9.  Positive Control
 Positive control is when the binding causes the
event.
 Negative Control
 Negative control occurs when binding of protein
prevents an event.

11.  Books:
 Genetics by Benjamin Pierce
 iGenetics by Peter J. Russell
 Internet:
 https://www.google.com/search?q=inducible+system+lac+opero
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ved=0ahUKEwiohPTA5c7dAhUV148KHTQ5BMUQ_AUIDigB&bi
w=681&bih=616