A hen’s egg can be seen easily. Is it a cell or a group of cells?
Answers
A hen’s egg is an example of a macroscopic cell. When laid the egg may be fertilised or unfertilised. If unfertilised, the egg contains a single celled haploid ovum. If fertilised the egg contains a single celled, diploid zygote, which is the result of fusion of the ovum with a sperm cell. However, as the zygote grows into an embryo, the single cell divides multiple times. Therefore, an embryo (contained within an egg) is multicellular.
Diagram of an egg, 9 days after being laid. Image by: By KDS4444 - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=59073031
Hen’s egg is an example of macroscopic egg. It is a single cell just like ostrich egg which is way bigger in size.
If the egg is fertilized, it will give rise to a new chick whereas if the egg is unfertilized, it will produce a haploid. When the egg is laid, the yolk content inside contains all the necessary nutrients required for the growth of the baby if the egg is fertilized.