Lecture 1

general introduction

How do scientists classify organisms

Based on their anatomy, morphology, evolutionary history, features of embryological development, and genotype

What’s the order of classification

Domain - Kingdom - Phylum - Class - Order - Family - Genus - Species

Whitaker R.H 1969

Classified living organisms according to the nature of their cellular structure, and their feeding pattern

Five kingdoms

1. Monera

2. Protista

3. Fungi

4. Plantea

5. Animalia

Subkingdoms of Animalia

1. Mesozoa

2. Parazoa

3. Eumetazoa

Features of Eumetazoa

1. Includes the rest of the animal kingdom

2. Multicellular with specialized cells

3. Clear original tissue

4. The structure of the body Ranges from simple to complex images

Features of Mesozoa

Very small and simple animals characterized by their slender body and lateral symmetry

Kingdom Mesozoa contain on phylum which is ?

Phylum:Mesozoa

What kind of animals are in the kingdom Mesozoa

Parasites

The parasites (Mesozoa) infect what kind of animals

Marine invertebrates

The Lateral symmetry of Mesozoa

Consists of an outer layer of ciliated digestive cells and is surrounded by an inner layer made up of reproductive cells

An example of Mesozoa

Rhoplura

Features of Parazoa

1. Reproduces sexually or asexually

2. Radially symmetrical or asymmetrical

3. Made up 2layers

4. Non specialized cells

5. Have different colors

6. Hardly any clear tissue

7. No digestive system

8. No nervous system or sensory cells

What the phylum of kingdom Parazoa

Phylum:Porifera

Where are Porfera found ?

Most in marine water and a few in freshwater

What are Spongocoel

Central cavities

What are the different shapes of Porifera

Branched, and irregular

How does digestion occur in Porifera

Interceptor and holozoic nutrition

How does respiration and excretion occur in Porifera

By simple diffusion

What are sponges made up of?

A system of tiny pours and canals that make up a filter feeding system

Sponge Anatomy

1. They have numerous tiny pores that allow water flow into the body and a large opening to allow water to flow out

2. small cells that line the canals of a sponge with flagella

Ostia

Numerous tiny pores that allow water to flow into the body

Oscula

one to several large openings that allow water to flow out of the sponge

Chanocytes

Small cells that line the canal of a sponge with flagella

function of Chanocyte

1. Maintain the floor water through the canal

2. trap food particles

Siliceous spicules (Hexactinellida)

Siliceous spicules (Demospongiae)

Spongin

Calcareous Spicules

Classes of Phylum: Porifera

1. Hexactinellidae

2. Calcarea

3. Demospongiae

Hexactinellidae

Calcarea

Calcarea

Demospongiae

The three types of canal systems

1. Asconoid

2. Synonoid

3. Leuconoid

Asconoid

Syconoid

Leuconoid

Asconoid features

1. Has the simplest body plan

2. Grows in colonies

3. Small and shaped like a tube

4. A single large opening

Where are Asconoid found

Only on Calcarea

Synconids features

1. Water expelled through one large osculum

2. Radial canals, along the sides of the body tube

Where are sycononids found

Mostly found in Calcarea and some in Hexactinellidae

Radial Canals

Choanocytes line individual canals

Example of syconoids

Sycon

Example of Asconoid

Leucosolenia

Leuconoids features

1. Most complex body plan

2. No spongocoel

3. Much greater body size

Where are leuconoids found

In all 3 classes

Example of Leuconoid

Euspongia

Leuconoid

Syconoind

Ascondnoid

Leucosolenia kingdom

Animalia

Leucosolenia subkingom

Parazoa

Leucosolenia Phylum

Porifera

Leucosolenia Class

Calcarea

Leucosolenia characteristics

The body wall is transparent with many tiny pores and surrounded by numerous triradiate spicules within the wall

The three layers of Leucosolenia are

1. The inner layer (enclosed cell layer)

2. Medium jelly

3. The outer layer or epidermis

The outer layer of Leucosolenia consist of

Disc cell and formaina cell

What does the medium jelly of Leucosolenia consist of?

Old cell, Muscle cells, gradular cells, and gum cells

Amoebic cell (old cells)

Mycocytes

Collencyte

Gland cells

What are the colors of asexual reproduction in sponges?

1. Budding

2. Renewal

3. Gemmules

What are GEMMULES

Configure circus or internal budding

Where are GEMMULES found

In freshwater sponges

GEMMULES

What are sponge larva called?

Amphiblastula

Amphiblastula

Amphiblastula

What are the uses of sponges commercially

1. Washing

2. Mattress manufacturing

3. Stuffed toys

Medical purposes of sponges

Antimicrobial compounds have been found on sponges like antibacterial, antifungal, and antiviral

Enclosed cell layer (the inner layer) contains

Choancyte and flagella

Amoebocyte

Choanocytes

Flagellum

Spicules

Osculum

Mesohyl

Ostia

Spongocoel

Choanocytes

Amoebocyte

Epidermis