Three events unique to meiosis are that synapsis and crossing over happen in prophase one, at the metaphase plate the chromosomes are paired in teatrads, also in anaphase one homologous chromosomes are separated and sent to opposite poles of the cell.
Answer:
d. secondary endosymbiosis.
Explanation:
- When a living cell acquires another organism that eventually becomes a part of this cell, this process is known as primary endosymbiosis.
- When an organism that has already undergone primary endosymbiosis engulfs another eukaryotic organism then this process is known as secondary endosymbiosis.
- Secondary endosymbiosis has been known to occur in plastids because of which they are surrounded by two membranes. This bilayer is present because one of the layers is the original outer membrane of the organism and the other membrane is that of the organism that has been engulfed.
A seed must be:
- light
- have gliders (wings)
- be formed like a parachute
- not to strongly attached to the flower