Answer:
The lack of Mad1 protein can cause faster cell division.
Explanation:
The Mad1 protein is responsible for regulating the fixation of chromosomes in spindle microtubules, during cell division. With the presence of this protein, anaphase is prevented from starting while the spindle, where the chromosomes attach, is formed.
Without this protein, this check is not done and cell division occurs faster, which is one of the reasons why cell division can be accelerated.
Answer:
b) In allosteric regulation, a small molecule binds to a large protein and causes it to change its shape and activity.
Explanation:
Allosteric regulation refers to the activity control of an enzyme by binding small molecules to regulatory sites on It. This binding causes an alteration of the protein conformation and consequently the shape of the active site and its catalytic activity are altered. Regulatory enzymes can act by either stimulating or inhibiting the activity of a protein.
Answer:
No 15N/15N labeled DNA was observed in second generation
Explanation:
Meselson and Stahl were doing an experiment to find out the semi-conservative mode of replication of DNA. The first cultured bacteria in 15N medium which was containing a heavy isotope of nitrogen. The DNA synthesized here had more density. After that they transferred the bacteria to the 14N containing medium. When bacteria reproduced and new strands of DNA were synthesized, they observed the following -
- The first generation had hybrid DNA with 15N/14N strands
- The second generation had both hybrid 15N/14N DNA and 14N/14N DNA strands
- There was no 15N/15N DNA observed.
In this way they proved that one strand of DNA is kept conserved during the replication.
Capillaries are tiny blood vessels in the body. Capillaries do not produce blood cells. Hope this helped