Answer:
club mosses
Explanation:
Microphyll is a type of plant leaf defined by the existence of a single non-branching rib. The present species that have microphiles have small and relatively simple leaves, associated with protosteal stems; however in the past there were representatives with microphiles up to one meter long. The most widely accepted theory about the origin of microfiles is that they evolved from lateral projections of the main axis.
Microphils are characteristic of club mosses, spike mosses, and quillworts leaves.
Answer:
Positive and negative ions
Explanation:
when these two come together it is considered ionic bonding.
Survival can possibly be one
Answer:
protect the cell from its surroundings.
Explanation:
Composed of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules and regulates the movement of substances in and out of cells.
Answer:
I, II and III
Explanation:
The melting temperature of a DNA double helix is affected by several factors that affect the hydrogen bonds and /or the other interactions involved in maintaining the helical structure. Two DNA strands of a helix are held together by the hydrogen bonds between the complementary nitrogenous bases. The pH of the solution would affect the hydrogen bonds. If the pH is too acidic, the hydrogen bonds acceptor atoms will accept protons from the solution and would not be able to make hydrogen bonds.
The ionic strength of the solution represents the ions present in it. If the solution has positively charged ions, the negative charges of phosphate residues of the DNA backbone will be neutralized. This would make the double helix more stable. Similarly, a longer DNA strand would have a higher melting temperature as more heat will be required to break more hydrogen bonds as compared to a shorter DNA strand.
