It is the nucleus that contains DNA and controls the functions of the cells
Answer:
a. The operon is under positive control
a.) Loss of enzyme synthesis results from loss of regulatory R gene product which is regulated in the presence of Tis ophane for transcription. Absence of (Tis), transcription is positively controlled by regulatory Rprotein
b.) The proposed model reveals Tis / B complex prevents Tis enzymes from undergoing transcription through the RB operator by binding to the B region
the role of the R protein is
-decrease affinity of Tis / B complex to B region of RB
-bind to the R region on RB
- change the conformation of B region
- yield decreased affinity of Tis / B complex when R gene is lacking preventing transcription in the process
Effects of the RB mutations is that R protein will not bind to Tis / B complex to reduce transcription
Infant suckling
<span>Infant suckling is the stimulus that is needed
for continued and sustained production of breast milk. When an infant suckles, stimuli
are transmitted to the mother's pituitary gland and prolactin (a hormone
responsible for milk production) is released by the pituitary and this leads to
the production of more milk. The more an infant suckles, the higher the
prolactin level and the amount of milk produced.</span>
Many of the organisms that had existed on the earth left no fossils because most of them can not meet the conditions that must be fulfilled before fossils can form. For fossils formation to occur, the organism soft tissue must decay leaving behind the hard part [majorly bone] in the sediment. Overtime, layers of sediment have to build up and pressed down on the buried remains. As time goes on, water and mineral seeped into the remains and form crystals.
