Fill in the Blanks Asexual and sexual reproductionOnline version Complete this fill-in-the-blanks daily review. by Belinda Schirmer 1 offspring species gene success biological identical finite genetic survive pool individual Reproduction means making a copy or a likeness . For living organisms , this means producing that are to the parent or resemble the two parents that gave rise to them . Individuals have a lifespan , so in order for a population or a species to , material must be passed from one generation to the next . This ability to reproduce is known as the reproductive of an individual . The genetic material of all organisms in a population makes up the . The likelihood of genes appearing in the next generation and being passed on is known as fitness . In evolutionary terms , reproduction is less significant for success and more important for the continuation of the . 2 zygote Sexual chromosomes fertilisation mitosis meiosis haploid embryo gametes fuse reproduction requires the production of male and female ( sperm and ova ) by the process of ( reduction division ) . Each gamete is with half the normal number of . The gametes during the process of to create a ( fertilised egg ) with the full diploid ( 2n ) complement of chromosomes . The cells of the zygote divide by , keeping the chromosome number constant , and the resulting continues to grow and mature into a new individual . 3 inside internally External large externally energy aquatic parental nourishment Internal dehydration fewer Fertilisation may take place or . External fertilisation occurs in or moist terrestrial environments , to prevent of gametes . Gametes must be produced in numbers to ensure success . Internal fertilisation takes place the body of the female and involves mate attraction and copulation , which require investment and put the organisms at risk of predation , but eggs need to be produced . fertilisation occurs in most invertebrates and some vertebrates ( fish and amphibians ) . fertilisation occurs in some invertebrates ( insects and snails ) and most vertebrates ( reptiles , mammals and birds ) . Other mechanisms that increase the chances of survival and continuity of species include for the developing young and care . 4 self germination pollination cross fruit environmental agents dispersal wind variation Sexual reproduction in plants involves external of pollination and seed , such as , water , fire ( abiotic ) and animals ( biotic ) . Pollination mechanisms in plants include - pollination ( to ensure survival if reproductive partners are scarce ) and - pollination ( to increase genetic and ensure survival if a sudden change such as disease or drought occurs ) . The life cycle of a plant involves , fertilisation , seed dispersal and . Seed dispersal relies on the type of in which the seeds occur matching the type of dispersal agent available in that environment . 5 rapid Budding wall variation DNA identical bacteria cleavage demise Hydra fission resources parent occurs in yeast and some multicellular organisms such as and brain coral . Binary is the most common form of asexual reproduction in and protists . Asexual reproduction in bacteria occurs in a series of steps : a cell grows to twice its size ; replicates ; DNA separates ; protein accumulates at the site ; the cytoplasm divides ; and a new is synthesised . Both binary fission and budding involve only one , so no mate is required , allowing proliferation of genetically organisms that are well suited to survive in their particular environment . Disadvantages of asexual forms of reproduction : lack of genetic in offspring , which may lead to their in unexpected harsh conditions or as a result of other changes in selecting agents ; the large numbers of offspring produced may compete with each other for .