How can asexual reproduction occur

Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Prev NEXT. Life Science. The human chromosomes hold the DNA of the human genome. Each parent contributes 23 chromosomes. Instead of a long loop of DNA like a bacterium, cells of plants and animals have chromosomes that hold the DNA strands. Humans have 23 pairs of chromosomes, for a total of 46 chromosomes.

Fruit flies have five pairs. Dogs have 39 pairs, and some plants have as many as Chromosomes come in pairs. Each chromosome is a tightly packed strand of DNA. There are two strands of DNA joined together at the centromere to form an X-shaped structure. One strand comes from the mother and one from the father.

Because there are two strands of DNA, it means that animals have two copies of every gene, rather than one copy as in an E. When a female creates an egg or a male creates a sperm, the two strands of DNA must combine into a single strand. The sperm and egg from the mother and father each contribute one copy of each chromosome. They meet to give the new child two copies of each gene. To form the single strand in the sperm or egg, one or the other copy of each gene is randomly chosen.

One or the other gene from the pair of genes in each chromosome gets passed on to the child. The "tall" version of the gene is normally the form that is found in the wild. The "short" version, in many cases, has a less active form of one of the enzymes involved in the synthesis of the hormone, so the plants are shorter. We refer to two genes as alleles of each other when they are inherited as alternatives to each other. The time between planulae formation and settlement is a period of exceptionally high mortality among corals.

Along many reefs, spawning occurs as a mass synchronized event, when all the coral species in an area release their eggs and sperm at about the same time. The timing of a broadcast spawning event is very important because males and female corals cannot move into reproductive contact with each other. Colonies may be separated by wide distances, so this release must be both precisely and broadly timed, and usually occurs in response to multiple environmental cues.

The short-term getting ready to spawn control is usually based on lunar cues, or cues from the moon. The final release, or spawn, is usually based on the time of sunset.

Planulae swim upward toward the light exhibiting positive phototaxis , entering the surface waters and being transported by the current. After floating at the surface, the planulae swim back down to the bottom, where, if conditions are favorable, they will settle.

Once the planulae settle, they metamorphose into polyps and form colonies that increase in size. Maybe in a parallel universe, but definitely not in this space-time. In the world of plants , there are numerous examples of asexual reproduction. Potatoes, daffodils, garlic, gladiolus, ginger, strawberry are just some of the types of plants that practice asexual reproduction. There are two ways plants do this.

First is known as vegetative reproduction. This means that new plants are created without seeds or spores. For example, ivy utilizes another root, other than the one that is on what could be considered the primary root, to grow new plants. The other way is called apomixis, and that means that the seeds are produced without fertilization.

In this case, from the ovary which is a diploid cell , new seeds rise. Plants that reproduce asexually have one huge evolutionary benefit. They can reach the mature stage much faster than others, as they mostly grow from already strong adult plants, having all the benefits in terms of protection and resource availability. Asexual reproduction is far less common with animals than it is with plants.