I looked it up and it should be D. Nerve cells :)
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Answer: Ectotherms depend on external heat sources. Their body temperature changes with the temperature of the environment. Endotherms generated heat internally to maintain body temperature.
Explanation:
Raynaud's phenomenon.
Scleroderma is a group of autoimmune diseases that may affect different parts of the body with special intensity in the skin. Some of the affected structures may be blood vessels. Because of this, when exposed to cold, vasoconstriction occurs and the Raynaud's phenomenon is manifested in the extremities of the body.
Answer:
Identify all the entities in the system. An entity should appear only once in a particular diagram. ...
Identify relationships between entities. Connect them using a line and add a diamond in the middle describing the relationship.
Add attributes for entities.
Explanation: