1. The cell wall has lignin (hard substance): to prevent the xylem vessel from collapsing and withstand high pressure.
2. The absence of protoplasm (nucleus + cytoplasm) and cross wall: to allow water to move through the lumen easily.
Hope it helped!
Answer:
Please see my answer below.
If you like my response you can mark it as brainliest.
If you have any doubts (no joke) you can reach out to me in the comments.
Explanation:
<em><u>The endosymbiotic theory states that some of the organelles in eukaryotic cells were once prokaryotic microbes. Mitochondria and chloroplasts are the same size as prokaryotic cells and divide by binary fission. Mitochondria and chloroplasts have their own DNA which is circular, not linear.</u></em>
When your body temperature rises because of an infection, it's called a fever<span>. </span>Fevers<span> are caused by chemicals called pyrogens flowing in the bloodstream. Pyrogens make their way to the hypothalamus in the brain, which is in charge of regulating body temperature.</span>
