Answer:
Selectively permeable or semipermeable means specific substances are allowed to pass through the plasma membrane.
Explanation:
The plasma membrane is selectively or semipermeable in nature because the plasma membrane allow only specific molecules such as nonpolar substances or hydrophobic substances such as steroidshormone to pass through it and prevent the passage of polar solute molecules such as water,glucose.
To transport these polar solutes across the membrane an additional protein is needed in case of transport of water channel protein is needed whereas in case of glucose transport carrier protein is required.
Well if you had 2 or more variables you might not know what is causing what.
Answer:
Just 5% to 10% of the sunlight they receive gets converted into energy. So if humans are going to photosynthesize, we'd better get good at it. We would probably evolve to become a lot bigger to absorb enough light to feed and grow.
Hope this was helpful!❤
Answer:
b. spores of two types to spores of one type
Explanation:
Spores of two types to spores of one type is not the trend to plant evolution because first the spores of one type is present in living organisms but with the passage of time evolution occurs that will leads to formation of spores of two types happen in living organisms. There are types of spores present in plants such as microspores, which produces male gametophytes, and megaspores, which produce female gametophytes while on the other hand, spores of one type is present in plants having asexual reproduction.
B) Viens
The veins have valves to keep the blood pumping out and not coming back in the heart.