Question
Question: Syngamy can occur outside the body of organisms in A) Algae B) Ferns C) Fungi D) Mosses...
Syngamy can occur outside the body of organisms in
A) Algae
B) Ferns
C) Fungi
D) Mosses
Solution
The exchange of DNA in the organisms helps in the diversification of the populations. Syngamy is one of the various ways through which the exchange of genes can occur. In most aquatic organisms, there is a requirement of an external medium (water) for exchanging genes i.e., outside the body of the organism.
Complete answer:
The fusion of two cells is Syngamy that produces a cell that has twice as many chromosomes.
The two cells undergoing fusion are known as gametes, and the cell produced is called a zygote. The aim of the syngamy is the renovation of genetic material.
-Fertilization is of two types-
External fertilization
In this type of fertilization, as the name suggests the syngamy occurs outside the body of an organism. For example - in most aquatic organisms like algae, fish, amphibians.
- There is great synchrony between the sexes for the organisms exhibiting external fertilization as they release a huge number of gametes into the surrounding medium in order to maximize the chances of syngamy. A very known case of algae, resulting in a large number of offspring.
The extreme vulnerability of these offspring to predators threatening their survival up to adulthood is one of the major disadvantages.
Internal fertilization
In the Internal fertilization, the Syngamy occurs inside the body of organisms. Example- fungi, birds, mammals.
Male gametes are released in proximity to the female gametes.
Additional information:
Ferns - in these spores are generally involved in the reproduction. Plants of ferns are of sporophyte generation which generally releases spores during the summer. Spores released on a suitable surface usually moist protected areas to promote germination and finally grow into gametophytes.
Fungi - they reproduce asexually by fragmentation, budding, or producing spores. The formation of asexual spores is the most common mode of asexual reproduction in fungi and produced through mitosis i.e from one parent and generally identical to that parent.
Moses - they don't have flowers. So, they reproduced using spores. The gametophyte of moss is generally stemmed which is simple or branched and upright or prostrate. The leaves of mosses are made up of thickened midribs with no internal air spaces.
So, the correct answer is, ” A) Algae”.
Note:
- The fusion of the male gamete with the female gamete to form a zygote is termed as Syngamy. The resulting zygote eventually develops in the new organism.
- The fusion of gametes usually takes place in water i.e outside the body of the plant in most of the algae. The gamete is present without any protections and consists of single cells.