Answer:
Muscles move body parts by contracting and then relaxing. Muscles can pull bones, but they can't push them back to the original position. So they work in pairs of flexors and extensors. The flexor contracts to bend a limb at a joint.
Explanation:
Answer:
This convection produces winds and ocean currents.
Answer:each gene in the gene pool exists at a certain rate, or the allele frequency.
Explanation:
<span>Type 2 alveolar cells or pneumocytes are the cells responsible for secreting pulmonary surfactant. Their function is important as the pulmonary surfactant is required to decrease surface tension within the alveoli. They are capable of cell division which in turn produces more of these alveolar cells when there is damage to the lung.</span>
Answer:
<em>The correct option is C) The helicase enzyme unwind the DNA molecule into two strands.</em>
Explanation:
DNA replication occurs in a semi-conservative manner. This means that each strand of the DNA can give rise to a new strand. For the process of DNA replication to begin, firstly it is necessary that the DNA unwinds. Topoisomerases are enzymes which are known to remove the super-coiling of the DNA. Helicases can be described as the enzymes which separate the two strands of DNA from the region where replication has to begin. Hence, option C is correct.
