Spines primarily have a protective function in plants. The spines can be sharp, and form a physical barrier against herbivores which may want to feed on the plant. Spines however also have other benefits. The spines on a jumping cactus allow segments of the cactus to stick to passing large animals or humans, thereby allowing the cactus to spread to other areas through asexual propagation. Spines are modified leaves, and spines have a much lower surface area than leaves, and therefore can reduce transpirative loss of water by the plant during harsh droughts. Some trees in alpine regions, such as pine trees, have developed spine-like leaves to prevent the accumulation of snow in the branches.
Answer;
-Serous membrane
Explanation;
-Serous membranes are thin membranes that lines the internal body cavities and organs such as the heart, lungs, and abdominal cavity. The thin membrane is made up of mesothelium tissue which originates from the mesoderm.
-These membranes consists of a single layer of flattened mesothelial cells applied to the surface of a thin layer of collagenous tissue that attaches to underlying endothoracic/transversalis fascia. They function to preclude adhesions among organs, thereby allowing organs to move freely relative to one another.
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