The surface layer of the water freezes solid creating a barrier that insulates the ice below so that it keeps a steady temperature usually a few degrees above freezing (32 degrees).
Explanation:
1) The enzyme helicase catalyses the unwinding of the two DNA strands by disrupting the hydrogen bonds between complementary base pairs.
2) Single-stranded binding proteins attach to the DNA strands to stabilise them and prevent them from joining back together.
3) The enzyme primase catalyses the addition of a short primer consisting of RNA nulceotides to the DNA strand. This serves as an 'anchor' DNA polymerase to initiate replication.
4) The enzyme DNA polymerase synthesizes a new DNA strand by incorporating DNA nucleotides complementary to the existing strand. DNA polymerase activity only occurs in the 5' ---> 3' direction.
5) The enzyme ligase catalyses the formation of hydrogen bonds between the two new pairs of DNA strands, and seals any breakages in the sugar-phosphate backbone.
Answer:
Hypothalamus
Explanation:
The hypothalamus is a part of the brain which possesses temperature receptor cells that detect changes in the man’s temperature, thereby sending signals in the form of electrical nerve impulses to the man’s muscles and nervous system, which in turn respond in counteracting the drop in the normal temperature of the body.
Once the muscle cells of this man receive these signals, they produce heat through thermogenesis by shivering when the muscle cells begin to contract. This is one of the mechanisms by which thermoregulation is achieved as controlled by the hypothalamus in the brain of the man.
