Explanation:
In biology, the term spore designates a single-celled or multicellular microscopic body that is formed for dispersion and survival purposes for a long time (dormancy) under adverse conditions, and which is generally a haploid cell. In many eukaryotic beings, it is a fundamental part of their reproduction, originating a new organism by dividing by mitosis (especially in fungi) or meiosis (plants), without having to merge with another cell, while in some bacteria it is instead a inactive stage, resistant to desiccation and for non-reproductive survival purposes. The term derives om the Greek σπορά (sporá), "seed".
The spore is an important element in the biological life cycles of plants, fungi, algae and some protozoa, which usually produce spores in structures called sporangia. In plants, spores are gametophytes within their life cycle and allow the dispersion of the propagules at the same time. Most fungi produce spores; those that do not are called asporogenic fungi.
Some arteries carry oxygenated blood just as some capillaries do.
Some veins carry deoxygenated blood just like some capillaries do.
Yes. During meiosis Diploid (2n) mother cell produces fou haploid(n) daughter cell.
Explanation:
- Meiosis is also known as Reduction division.
- It is type of cell division by which a diploid mother cell produces haploid daughter cell.
- It is termed as reduction division because the number of chromosomes are reduced to half in daughter cell.
- Meiosis occurs only in sex cells to produce gametes.
- Significance of meiosis lie in the fact that it reduces the number of chromosome into half and thus helps to maintain the chromosomal number of the species in the zygote after fertilisation .
- Meiosis has two steps : Meiosis I and Meiosis II. There is a time gap between two steps, called interkinesis.
- Meiosis I involves replication , crossing over etc.
- Meiosis II is similar to mitosis however, no DNA replication occurs prior to meiosis II and the DNA content is thus halved in Daughter cell.
