Answer:
Pteridophytes are vascular plants but they do not produce flowers and seeds which mean their source of reproduction is unknown or hidden.
On the contrary, Spermatophytes as the name indicates, are seed bearing plants. They produced seeds and flowers. Examples are flowering plants, cactus, leather flower, buttercup and may more.
Explanation:
I think the correct answer from the choices listed above is option 3. The term that correctly identifies the process by which molecules move through the dialysis tube membrane would be diffusion. <span>The molecules move from a region where they are in high concentration to a region where they are in low concentration.</span>
Answer: anthropochory (human dispersal)
Explanation:
Assuming that the bird pollinators were significantly diminished, human dispersal will be a useful means of dispersal. Currently, in the tropics, Jatropha is intentionally planted by individuals for oil production.
Answer:
In this case, it is likely that the polypeptide chain assumed an alpha helix configuration because the lipid bilayer did not have beta-barrel proteins.
Explanation:
A polypeptide chain is naturally polar, however, a lipid bilayer is naturally non-polar. This makes it difficult and even prevents the polypeptide chain from crossing a lipid bilayer, since the composition of these two elements does not allow them to mix. In that case, the polypeptide chain has two options to take to successfully cross the lipid bilayer.
The first option that the polypeptide chain has is to allow the creation of twisted beta sheets in the shape of a closed barrel in its structure. This only works if the lipid bilayer has beta barrel proteins in its composition to act as a transport channel for the polypeptide chain. However, few lipid layers have this protein.
Most likely, the polypeptide chain assumes an alpha helix conformation to cross lipid bilayers that do not have beta-barrel proteins. By assuming the beta conformation, the polypeptide chain reinforces the hydrogen bonds present in its composition, allowing it to cross the lipid bilayer without having its conformation and structure disassembled.
