3: B Nervous system. 4: A Sensing and responding to its external environment.
Answer:
A) The male stamens hold the pollen, the female pistil holds the ovule, and the petals attract pollinators.
Stamens (male reproductive parts of a flower) collectively forms the male reproductive organ (androecium) in a flower whereas pistil (the female reproductive part of a flower) forms the female reproductive organ called gynoecium.
Stamen consists two parts that are anther (that produces pollens, male reproductive cells) and a stalk like structure called filament, which supports/ holds pollen producing anther.
The female pistil holds the ovule that is enclosed by ovary in flowering plants (angiosperms) and the petals in a flower attract pollinators.
Thus, option A) is the right answer.
Answer:
C. HMG-CoA reductase will be dephosphorylated
Explanation:
When a low density lipoprotein particle is taken up by the cell, the impact it will have on the regulation of de novo cholesterol synthesis will be HMG-CoA reductase being dephosphorylated.
HMG-CoA( 3-hydroxy-3-methyl-glutaryl-CoA reductase) is an enzyme which aids the synthesis of lipids. When the lipids are produced and taken up by the cells then the effect of the synthesis stops to avoid excess synthesis and to allow for the action of enzymes which will act ok them in the cells . This is why it leads to a dephosphorylation of the enzyme which stops the action.