Answer:
D. There was a single transition from aquatic to terrestrial habitats
Explanation:
Based on the molecular differences at the level of DNA sequence and inheritance, the molecular phylogenies show that all land plants are a monophyletic group. This is why it suggests a single transition from aquatic to terrestrial habitats occur.
Protects the plant from losing water. The sharp needles of the tree mean that is has less surface area for the sun to make contact. They may also have differently shaped stomata, in order to prevent water loss
<span>Only one sperm normally fuses
with an egg because if more than one sperm fuses, through a process
called polyspermy, development of the zygote usually stops.
</span>
<span>Fertilization of one egg by
two sperm is possible, but the resulting zygote is almost never viable
because such a zygote would have three sets of chromosomes instead of
the normal two. This condition, called triploidy, is usually
incompatible with life. Those rare triploid infants that do survive to
term have severe and multiple birth defects and rarely live more than a
few days. </span>
The plant cells communicate across cell walls through Plasmodesmata.
how do plant cells communicate across cell walls?
- Between tiny channels woven through the walls of neighboring plant cells, plant cells can communicate with one another through channels referred to as plasmodesmata.
- These channels enable chemicals to move freely between cells, allowing plants to grow regularly and form tissues and organs.
- However, plasmodesmata also act as entryways that viruses can employ to infect an increasing number of cells.
- Given these advantages and disadvantages, plants must balance the permeability of their plasmodesmata in order to move materials from one cell to another while preventing the spread of infection.
Learn more about the Plasmodesmata with the help of the following link:
brainly.com/question/6220658
#SPJ4
4.
Myelin Sheath is an insulator on the axon
Hope that helps! :)
