Give scientific terms for the following:
A haploid reproductive or sex cell taking part in sexual reproduction forming the diploid zygote.

Explanation

To answer the question, we need to identify the scientific term for a haploid reproductive or sex cell involved in sexual reproduction that ultimately forms a diploid zygote.

### Step-by-Step Solution:

1. **Understanding the Concept of Gametes**: In sexual reproduction, organisms produce specialized cells known as gametes. These gametes are haploid, meaning they contain half the number of chromosomes compared to the diploid somatic cells of the organism.

2. **Identifying Male and Female Gametes**: In flowering plants, the male gamete is produced in the pollen grains and is called the sperm cell. The female gamete is produced in the ovule and is referred to as the egg cell.

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