Reproduction – Sexual and Asexual
Definitions
Asexual Reproduction Asexual reproduction is a mode of reproduction that does not entail the union of sex cells or
gametes. Unlike in sexual reproduction wherein male and female gametes unite to reproduce an
offspring, in asexual reproduction, this union is not necessary. The organism can reproduce in the
absence of a mate in which, in this case, produces an offspring which is usually a clone of the parent.
The different types of asexual reproduction are binary fission, budding, vegetative propagation,
spore formation, fragmentation and parthenogenesis.
 Binary fission is a type of asexual reproduction where a parent cell divides, resulting in
two identical cells, each having the potential to grow to the size of the original cell.
Common among prokaryotes
 Budding is the formation of an outgrowth (bud) from an organism. The bud is capable
of developing into a new individual. Common in both prokaryotes and eukaryotes.
 Plant propagation happens by way of separating new plant individuals that emerge
from vegetative parts, such as specialized stems, leaves and roots and allow them to
take root and grow. Common in plants.
 Spore Formation is a method in Asexual Reproduction. Many Spores are stored in sacs
called Sporangia. When Sporangia burst; minute single-celled, thin or thick walled
structures called spores are obtained. Under suitable conditions, they develop into a
new Plant. Common in Fungi or Algae.
 Fragmentation is a form of asexual reproduction wherein a parent organism breaks
into fragments, each capable of growing independently into a new organism. Common
to sea stars, annelid worms and plants etc.
 Parthenogenesis is a form of asexual reproduction wherein the offspring develops
from the egg or female gamete without the prior fertilization from the male gamete.
Common in plants and insects.
The organisms that reproduce through asexual means are bacteria, archaea, many plants, fungi, and
certain animals.
Sexual Reproduction Sexual reproduction is a mode of reproduction involving the fusion of haploid female gamete (egg
cell) and haploid male gamete (sperm cell). The fusion of these gametes occurs at fertilization
resulting in the formation of a diploid zygote. The zygote develops into an individual organism that is
genetically distinct from the parent organisms. Sexual reproduction has the advantage over asexual
reproduction in increasing genetic variation and expanding the gene pool. Furthermore, it ensures
that the chromosome number of a particular species will remain the same across generations. Two
major types of sexual reproduction are syngamy and conjugation.
 Syngamy is the fusion of gametes resulting in the formation of a zygote, which
develops into a new organism. Most commonly known as fertilization and is used by
most sexually reproducing organisms like humans.
 Conjugation is different from syngamy in such a way that two organisms come
together in a temporary fusion to exchange micronuclear material. This can be
observed among single-celled organisms, such as bacteria, protozoans, and singlecelled fungi. While syngamy is a permanent fusion of the two cells, conjugation is a
temporary fusion of two cells.