Answer:
They have helical thickening of lignin in their walls to prevent collapse
Explanation:
the primary function of Xylem and its conducting vessels tracheids is to provide support and tranport water and minerals in plants.
Xylem vessels have layers of dead materials in the walls called LIGNIN. Lignin is a polymer; a very strong, hard materials that stop water passage through it,because it contains dead cells,
Therefore the presence of deposit of these strong impermeable, ligified walls in its walls prevent its collapse during mass flow of water of transpiration pull.
<span>B. are caused by the gravitational pull of the sun and the moon</span>
The coenzymes of <u>folate </u>b-vitamin are needed for the synthesis and maintenance of new cells
<h3>What is
b-vitamin?</h3>
B vitamins are a group of water-soluble vitamins that are crucial for red blood cell production and cell metabolism. Despite having names that sound similar (B1, B2, B3, etc.), these vitamins are chemically different substances that frequently coexist in the same foods. Dietary supplements that include all eight are typically referred to as vitamin B complexes. The exact number or name of each vitamin, such as B1 for thiamine, B2 for riboflavin, and B3 for niacin, is used to identify individual B vitamin supplements. Some substances, like pantothenic acid, biotin, and folate, are better known by their names than by their chemical names.
Each B vitamin either functions as a cofactor (usually a coenzyme) for important metabolic processes or functions as a precursor required to produce one.
To learn more about b-vitamin from the given link:
brainly.com/question/12004285
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saliva in mouth
pepsin,hcl,and mucus are responsible for digestion of food
