Fill in the following blanks with suitable words :
The changes which occur in boys and girls at puberty are brought about by various ………………….

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a word that describes what brings about the changes in boys and girls during puberty.

2. **Identifying Key Concepts**: During puberty, both boys and girls experience various physical and emotional changes. These changes are not random; they are regulated by specific substances in the body.

3. **Recognizing the Role of Hormones**: The transcript mentions that hormones are responsible for the changes that occur during puberty. Specifically, it highlights estrogen in females and testosterone in males as key hormones that trigger these changes.

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