Answer:
Semi-conservative DNA replication:
The semi-conservative model of DNA replication explains that the newly synthesized daughter DNA molecule contains one newly synthesized strand and one parental strand. This model of replication is important and explains the biological significance of replication. The DNA unwinds in this mode of replication.
Conservative model of DNA replication:
The conservative model of DNA replication explains that the newly synthesized daughter DNA molecules has the one DNA helix of parent and the other DNA helix are entirely new. This model does not has a biological significance. The DNA is not unwinds in this mode of replication.
The semi-conservative mode of DNA replication is found in the living organism.
Answer:
The correct answer would be non-disjunction.
Down syndrome refers to the genetic disease caused by the non-disjunction of chromosome number 21.
Non-disjunction refers to the event in which the homologous chromosomes or sister chromatids fail to separate properly during a cell division.
In Down syndrome, the sister chromatids of chromosome 21 fail to separate properly which results in the formation of a gamete with 2 copies of chromosome 21.
When this gamete fertilizes with another gamete, it results in the formation of a zygote with 47 chromosomes, that is, 46 chromosomes + extra copy of chromosome 21.
Answer:
The correct answer is - option D. gate- control theory of pain.
Explanation:
Gate control theory of pain suggests that non painful stimulus that inhibits or closes the the gates for the stimulus of the pain. This mechanism helps in the prevention of of the pain sensation to travel to the CNS. It is also refereed as the doorway in the spinal cord that is passed from the signals.
Thus, the correct answer is - option D. gate- control theory of pain.
Answer: Phytoplankton & Cyanobacteria
Explanation: They produce their own food
