Learn Biology: Kingdom Animalia: Phylum Porifera |iKen | iKen Edu | iKen App

Summary

This video explores the kingdom Animalia, focusing on invertebrates, particularly the phylum Porifera, which includes sponges. It details their simple structure, specialized cells for protection, water circulation, and food storage, as well as their unique nutrition and reproductive methods. Sponges primarily live in marine environments and have the ability to regenerate and reproduce both sexually and asexually. The video also touches upon the evolutionary relationship between sponges and colonial flagellated protozoa. Through this, viewers gain an insight into the biological characteristics and fascinating life cycle of sponges.

Takeaways

• 😀 Kingdom Animalia includes multicellular, eukaryotic organisms that are highly differentiated with tissues.
• 😀 Kingdom Animalia is divided into two major groups: invertebrates (without a backbone) and vertebrates (with a backbone).
• 😀 Invertebrates are further classified into eight phyla, including Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, and Echinodermata.
• 😀 Phylum Porifera consists of simple animals known as sponges, which are most common in marine environments but also found in freshwater.
• 😀 Sponges are radially symmetrical or asymmetrical, and their bodies are cylindrical, hollow, and branched.
• 😀 Sponges have a skeleton made of calcareous or siliceous spicules and fibers, providing structural support.
• 😀 The body structure of sponges is organized by specialized cells such as pinacocytes, choanocytes, and amoebocytes, which perform different functions.
• 😀 Sponges feed through a process called holozoic nutrition, capturing food particles from water currents created by choanocytes.
• 😀 Sponges reproduce both asexually (by budding, fragmentation, or regeneration) and sexually (with fertilization occurring inside the sponge body).
• 😀 Some well-known examples of sponges include Euplectella (Venus flower basket) and Spongia (bath sponge).
• 😀 It is believed that sponges may have evolved from colonial flagellated protozoa due to similarities in digestion and larval development.

Q & A

What is the kingdom Animalia and how is it classified?

The kingdom Animalia includes multicellular, eukaryotic organisms. It is classified into two main groups: invertebrates, which are animals without a backbone, and vertebrates, which are animals with a backbone.

How many phyla are there in the invertebrates, and can you name them?

Invertebrates are classified into eight phyla. These are: Phylum Porifera, Phylum Cnidaria, Phylum Platyhelminthes, Phylum Nematoda, Phylum Annelida, Phylum Mollusca, Phylum Arthropoda, and Phylum Echinodermata.

What is Phylum Porifera and what animals does it include?

Phylum Porifera includes animals commonly known as sponges. These animals are mostly found in marine environments, though around 150 species live in freshwater.

What are the structural features of sponges?

Sponges have a simple structure, which is either radially symmetrical or asymmetrical. They are highly branched, cylindrical, and hollow, with a cavity called the spongocoel enclosed by the body.

What type of skeleton supports sponges?

The skeleton of sponges is made up of calcareous or siliceous spicules and fibers.

What are the different types of specialized cells found in sponges?

Sponges contain three types of specialized cells: Pinacocytes, which form the protective layer; Choanocytes, which maintain water currents inside the body; and Amoebocytes, which store reserved food.

How do sponges obtain nutrition?

Sponges obtain nutrition through a hollow zoic mode of nutrition. They capture food brought by water currents created by choanocytes, which is then digested intracellularly.

How do sponges perform respiration and excretion?

Sponges perform respiration and excretion through simple diffusion. These processes do not involve specialized organs but rely on the movement of water through the body.

How do sponges reproduce?

Sponges reproduce both asexually and sexually. Asexually, they reproduce through budding, fragmentation, or regeneration. Sexually, male gametes are released into the water, fertilizing eggs in another sponge, leading to the formation of a new individual.

What are some examples of sponges?

Examples of sponges include Luca, Selenia, Psychonoskaya, Venus flower baskets, and Bath sponges.

Why are sponges believed to have evolved from colonial flagellated protozoa?

Sponges are thought to have evolved from colonial flagellated protozoa due to similarities in intracellular digestion and the resemblance of their blastula larvae to flagellated protozoa.