How do corals asexually reproduce?

Corals can reproduce asexually and sexually. In asexual reproduction, new clonal polyps bud off from parent polyps to expand or begin new colonies. This occurs when the parent polyp reaches a certain size and divides. This process continues throughout the animal’s life.

How do echinoderms reproduce asexually?

Asexual reproduction is by fragmentation, a part of an arm and part of the central disk becomes detached from the “parent” and develops into an independent individual sea star. In the past, many sea stars have been “killed” by chopping them into pieces but they have been able to regenerate and grow into more sea stars.

How do sea stars reproduce asexually?

Asexual reproduction in starfish takes place by fission or through autotomy of arms. In fission, the central disc breaks into two pieces and each portion then regenerates the missing parts.

How do sea urchins form a fertilization envelope?

In the sea urchin, contents of the cortical granules are secreted within 30 sec of insemination. Several of these content proteins then bind to the nascent vitelline layer of the egg and lift off the cell surface to form a stable, impervious, fertilization envelope.

How do sperm recognize and bind to the egg?

As the sperm approach the egg, they bind to the zona pellucida in a process known as sperm binding. This triggers the acrosome reaction, in which the enzymes of the acrosome are freed. These enzymes then begin to digest the zona pellucida and allow the sperm to tunnel toward the egg’s plasma membrane.

How do starfish sea urchins and sea cucumber reproduce?

Echinoderms can regenerate missing limbs, arms, spines – even intestines (for example sea cucumbers). Some brittle stars and sea stars can reproduce asexually by breaking a ray or arm or by deliberately splitting the body in half. Each half then becomes a whole new animal.

How does bryophyllum reproduce?

Bryophyllum plants can be reproduced by vegetative propagation by using either a piece of its stem or its leaves. If a broken piece of the stem of a Bryophyllum plant in the ground, we will get a new Bryophyllum plant growing from it in a week’s time.

How does a bread mold reproduce its own kind?

Bread mould reproduces asexually by spore formation. Black bread mould is a common form of fungus. It reproduces and grows in the same way as other moulds. The mould develops spores within a sporangium during asexual reproduction.

How does asexual reproduction occur in stem?

Asexual reproduction in plants occurs through budding, fragmentation, vegetative propagation, and spore formation. No flowers are required for this method. The plants produced by asexual reproduction thrive well in stable environments.

How does bread mold reproduce asexually?

The fungi usually reproduce asexually by producing sporangiospores. The black tips of bread mold, Rhizopus stolonifer, are the swollen sporangia packed with black spores. When spores land on a suitable substrate, they germinate and produce a new mycelium.

How does fish reproduction occur?

In most cases, the female drops eggs in the water which are immediately fertilized by sperm from the male. Another way is for fertilization to occur within the females body before she drops them into the water. With the third and final method, the female retains the eggs within her body and the young are born alive.

How does recognition of egg and sperm occur in sea urchin?

Once the sea urchin sperm has penetrated the egg jelly, the acrosomal process of the sperm contacts the surface of the egg (Figure 7.14A). A major species-specific recognition step occurs at this point. The acrosomal protein mediating this recognition is called bindin.

How does reproduction in butterfly begin?

Reproduction in butterflies begins with courtship, during which the male vigorously flaps its wings, releasing a dust of microscopic scales carrying pheromones above the female’s antennae. These male pheromones act as a sexual stimulant to the female.

How does sea urchin fertilization work?

During fertilization in a sea urchin, the sperm and egg undergo reactions that allow a sperm to recognize and fuse with the egg, followed by other reactions that prevent additional sperm from entering the egg. When more than one sperm cell fuse with one egg, this phenomenon is referred to as polyspermy.

How does the fertilization envelope form in sea urchins what is its function *?

In the sea urchin, contents of the cortical granules are secreted within 30 sec of insemination. Several of these content proteins then bind to the nascent vitelline layer of the egg and lift off the cell surface to form a stable, impervious, fertilization envelope.

How does the sperm activate the egg?

Egg activation is initiated by or temporally coincident with sperm entry in many animals, therefore, the fertilized egg must first complete the second meiotic division to form the haploid maternal pronucleus then mediate fusion of the male and female pronucleus while transitioning from a meiotic cell cycle to the …

How fast does sperm travel?

The swimming speed of human sperm in fluid is approximately 5 mm/min, so in theory, sperm could swim through the cervical canal in a matter of minutes or hours. In reality, some sperm have been found in the upper reaches of the uterine tubes within minutes of coitus.

How is regeneration a form of asexual reproduction?

Regeneration is a type of asexual reproduction in which the organism is capable of regrowing certain body parts. Regeneration occurs via mitosis. … Since the egg is haploid, it produces organisms which are also haploid. In some cases, the organism can regain its diploid number of chromosomes.