Reproduction in Organisms Test - 11

life cycle of organism’s starts from growth and development followed by reproductive phase. After that senescence phase starts in which degenerative changes starts which is generally irreversible and leads to death of organisms.

During mitosis division two daughter cells are produced having same number of chromosome. In meiosis division four daughter cells having half the number of chromosomes are produced. So, haploid organisms follow mitosis division.

Development of individual from unfertilized ovum is called parthenogenesis. The individual is haploid as no fusion of gametes occurs. Honey bee is of three kinds namely queen, drone and worker. Workers are produced parthenogenetically.

Apomixis is modified form of reproduction in plants in which seeds are formed without fusion of gametes. The diploid cell of nucellus develops into an embryo giving a diploid seeds.

Senescence is a natural process followed by maturity of organism. The metabolic processes of organisms start slowing down in this process leading to wear and tear of vital body organ. Nutrition does not affect the process of senescence.

Mode of reproduction mainly depends upon natural habitat of organism and internal physiology of organism. Favorable and unfavorable condition is also deciding factor in some lower organism.

Parrot has longest life span out of the given organisms. Parrot life span is about 140 years. The other organism given, life span is less than 50 years.

No individual is immortal except single celled organisms. Single celled organisms reproduce by cell division in which body parts divide into two or more parts to produce new organisms. Since no older organism is left, they are immortal.

Vegetative reproduction is a type of asexual reproduction. In vegetative reproduction no gametes formation takes place followed by fusion of gametes. It is mode of reproduction in plants.

Reproduction is essential for continuation of species as is organism has fixed life span. New organisms with similar traits are produced via reproduction. Organism can survive without reproduction. A number of infertile couples also leads their normal life.