9. Fungi & Porifera Flashcards
Organismal Complexity
- Protoplasmic
- Cellular
- Cell-tissue
- Tissue-organ
- Organ-system
Protoplasmic
Unicellular
Cellular
Colonial
- Aggregation of undifferentiated cells
- Choanoflagellates
Multicellular
- Aggregation of cells that are functionally different
- Sponges
Cell-tissue
- Cells aggregate into patterns or layers
- Tissue - A group of cells organized to perform a common function
- True tissue secretes extracellular matrix in form of a basement membrane on which cells sit
- Cnidarians, Sponges
Tissue-organ
- Organs contain more than one type of tissue
- More specialized function
- Platyhelminthes
Organ-system
- Organs work together in a system
- Other eukaryotes
Fungi
- Yeasts
- Rusts & Smuts
- Mould & Mildew
- Mushrooms
Fungi
- Unicellular & Multicellular
- Originally classified as plants
- Cell walls made of chitin
Nutrition in Fungi
- Extracellular digestion
- Release digestive enzymes into the environment and then absorb nutrition through cell walls
Porifera
- No organs or true tissues
- No nervous system or sense organs
- Adults sessile and attached
- Limited body movement
- High totipotency
- All aquatic - mostly marine
- Radial symmetry or no symmetry
Basic structure of sponges
- Many tiny ostia for incoming water
- One to several large oscula
Ostia (sing. ostium)
Pores for incoming water
- Combines into oscula
Oscula (sing. osculum)
Water outlet
- joint ostia
Three basic types of sponge
- Asconoid
- Syconoid
- Leuconoid
Asconoid Sponges
Flagellated Spongocoel
- Water enters through ostia into spongocoel
- Spongocoel is lined with choanocytes
- Water is pulled out of a single large osculum
Syconoid Sponges
Flagellated Canals
- In through incurrent canals
- Into radial canals through prosopyles
- Radial canals are lines with choanocytes
- Into Spongocoel through apopyles
- Exits through osculum
Leuconoid Sponges
Flagellated Chambers
- Most have numerous oscula
- No Spongocoel
- Incurrent canals
- Flagellated chambers
- Excurrent Canals
Pinacocyte
Epithelial type cells
- Closest thing to a tissue
Porocytes
Pore cells - Only in asconoids
Choanocytes
Flagellated collar cells
- One end embedded in mesohyl, other end exposed
- Move water and collect food through phagocytosis
- Exposed end: Flagellum surrounded by a collar of microvilli
- Collar forms a filtering device for food particles
Archaeocyte
Amoeboid cells
- Move through mesohyl
- Receive particles for digestion from choanocytes
- Transport food to other cells
- Transport oxygen to other cells
ECM
Extracellular Membrane
Skeletal Structure of Sponges
Collagen occur through the ECM of all sponges
Spongen
- A form of collagen secreted by class Demospongiae
- Form skeletal network of some sponges
Spicules
Many different shapes - Can be used to classify sponges
