Commonly, in sexual reproduction of unicellular and colonial algae, two specialized, sexually compatible, haploid gametes make physical contact and fuse to form a zygote.
kˈɑːmənli, ɪn sˈɛkʃuːəl ɹᵻpɹədˈʌkʃən ʌv jˌuːnɪsˈɛljʊlɚ ænd kəlˈoʊnɪəl ˈælɡiː, tˈuː spˈɛʃəlˌaɪzd, sˈɛkʃuːəli kəmpˈæɾᵻbəl, hˈæplɔɪd ɡˈæmiːts mˌeɪk fˈɪzɪkəl kˈɑːntækt ænd fjˈuːz tə fˈɔːɹm ɐ zˈaɪɡoʊt.