global English and language change from our blog. Blog. A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today. Definition and synonyms of scavenge from the online English dictionary from Macmillan Publishers Limited.
In human fertilization, two 1n haploid cellsâan ovum (female gamete) and a sperm cell (male gamete)âcombine to form a single 2n diploid cell called the zygote.n fungi, the sexual fusion of haploid cells is called karyogamy. The result of karyogamy is a diploid cell called a zygote or zygospore. This cell may then enter meiosis or mitosis depending on the life cycle of the species.
Spirogyra forms nonmotile gametes. Spirogyra undergoes sexual reproduction using a process called conjugation. First two haploid filaments of opposite mating types (+ and -) line up side by side. Each cell then forms an extension that grows towards a cell on the opposite strand. The tubes fuse forming conjugation tubes. The content from the cell of (-) strain travels through the tube and fuse with the cytoplasm of the cell of the (+) strain. The protoplast (the entire living portion of the cell) of each individual organism thus act as an isogamete until they fuse. The diploid zygote develops the zygospore.