<em>sieve tube elements are the cells of phloem which allow transportation of photosynthates through phloem...
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how sieve tube elements form sieve tubes:
</u>sieve tube elements are connected end to end and form a long chain which is called sieve tube,,,,
sieve tube elements are connected with the help of a side chain with the help of peptide bond...also one element has tapering end which easily overlaps with other end of next element to form sieve tube,,,,</em>
<span>Facilitated Diffusion-
Does not use energy. Membranes in the cell membrane pick up molecules & carry them across the membrane from high to low concentration</span>
Mid ocean ridges occur where two tectonic plates diverge or move away from each other. This separation occurs under the ocean.The Mid-Atlantic Ridge is such an example and is where the North and South American plates pull away from the Eurasian and African plates. Mid ocean ridges are usually a combination of divergent and transform plate boundaries. At transform boundaries plates slide past each other in opposite directions.
<u>T cells lymphocytes </u>are a type of white blood cell that actively target and destroy infected cells via the production of antibodies.
D is the answer hope this helped