<span>Epithelial tissue is densely packed cells that used most in the area where protection is needed. This cells mostly used in skin, some with more keratin which will increase their ability to protect. In bone, the main protective layer is calcium mineral which was deposited by osteocytes. Because this bone doesn't really need more epithelial cells. Bone tissue only needs a good vascularization and connective tissue to support it.
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Antigens are usually the proteins
A: Observation
Explanation: Scientist had to measure the worm to get its actual size, therefore they observed the size of the worm
Answer:
Rhizobium is present inside the nodule of bean if we observed with the help of hand lens.
Explanation:
Rhizobium is a type of bacteria which is present inside the nodules of various leguminous plants. The main function of this bacteria is to convert the atmospheric nitrogen into nitrates form for the plant. These bacteria is also called nitrogen fixing bacteria. They make a symbiotic association with the plants. The plant provides food to the bacteria while bacteria provides nutrients so both get benefits from each other.