Mollusca

Bryophytes, Molluscs, PoriferaNisha Jain, Dionne Sannen, Oriana Navarro, Namrata Jethmalani, Michelle de Zeeuw, Ali Capriles 1BryophyteWhat are they? Land plants that do not have vascular tissues

They are separated into 3 main categories:MossLiverwortHornwort

What does this mean?Vascular Tissues are xylem and phloemThey do not have the veins that other plants do that transport food and water throughout the plant

Examples

HornwortCoontail/ Anglo-Saxon Wort

Crystalwort

Crescent-cup liverwort

Hair Cap moss

White Tipped Moss

What is special about Bryophytes?The dont reproduce with seeds or flowers

Instead they have reproductive structure gametangia and sporangia.

Essentially, they produce SPORES

What is a spore? A small, usually single-celled reproductive body that is highly resistant to desiccation and heat and is capable of growing into a new organism

MolluscsFeatures!Molluscs have such a varied range of body structures that it is difficult to find defining characteristics that apply to all modern groups. The two most universal features are a mantle with a significant cavity used for breathing and excretion, and the structure of the nervous system.

3 Main Body Parts:FootVisceral MassMantle

Striking feature: use of the same organ for multiple functions. Ex: the heart and nephridia ("kidneys") are important parts of: reproductive system & circulatory and excretory systems In bivalves, the gills both "breathe" and produce a water current in the mantle cavity, which is important for excretion and reproduction.

Examples! Cuttlefish

Slug

Snail

Octopus

Nudibranchs

Squid

Fun Facts>100,000 species=2nd largest phylum of animals

Largest marine phylum, comprising about 23% of all the named marine organisms.

PoriferaCommonly known as sponges

36There are 5,000 species of sponges!Classified under the Porifera phylum:Hexactinellida (glass sponges)Demospongiae Calcarea (calcareous sponges)

Example: Hexactinellida

Example: Demospongiae

Example: Calcarea (calcareous sponges)

Favorite Sponge of All

FeaturesHave no main organs/tissues Unique Feeding System!

No mouths!

Tiny pores in their outer walls through which water is drawn.

Cells in the wall of the sponge filter the nutrients needed!

47Pumped to other parts of the sponge through big openings!

The cells preform many bodily functions which makes them appear more independent (comparing to other animal cells)Sponges can remold their bodies. Cells can move and change from one type to anotherMade up of a jelly like substance incased between two layers of cells!

Sponges are hollow!

Need something solid to grow on!Fun fact: On average, a porifera with 10cm body length can filter 100 liters of water everyday.

Similarities and DifferencesMolluscs and Sponges

55SimilaritiesInvertebrates- No Backbone

Marine Animals!

DifferencesMolluscs are more diverse - Have seven different classes

Sponges only have 3Sponges cannot live on land molluscs can

Sponges cannot be eaten molluscs can be!

Sponges do not move= attached to bottom permanent location

Molluscs move very slowly

Sponges have: no mouth, brain or organ nervous system!Molluscs have: 3 Main Body Parts: Foot, Visceral Mass and Mantle Questions?