Answer: A.
Explanation:
The secondary growth of a plant happens in the vascular cambium. When the vascular cambium produces more tissues, it makes the stems thicker over time.
An embryonic stem cell is the first cell in the embryo, this is what creates a human and helps more cells to form.
False
crossing over occurs in prophase 1 of meiosis 1. The significance of this crossing over is to ensure cell differentiation. If this occurred in prophase two it means the cells in meiosis 1 will be identical.
The portion of the membrane that faces the lumen is called the apical membrane.
Membrane is the lipid bilayer that surrounds the cell on its outer surface. The membrane serves various functions like: protection, cell shape and integrity and regulate the traffic of molecules across the membrane. It is semi-permeable in nature.
Lumen is the hollow portion present inside any organ or tube like the artery or intestine. It is a Latin word that means 'an opening'. The lumen of different organs served various purposes. However, the major function is the transport of substances like air, nutrients, waste materials, immune cells, hormones, etc.
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Answer is C hope it helps
