Animal Diversity - Sponges

All cells in an individual organism have the same DNA but the _____ binding to the DNA changes when and where a gene is expressed

Transcription factors

Transcription factors can…

Affect when, where, and how much the genes is expressed.

All cells in an individual contain the _____ genes.

same

What makes something an animal?

• Multicellular eukaryote

• Ingest nutrients & lack cell walls

• Motile at some point in life

• Characteristic development (blastula)

Blastula

Hollow mass of cells

Blastocoel

Cavity of blastula

What are the two major early evolutionary branches?

Parazoans and Eumetazoans

Eumetazoans have…

Distinct, specialized tissues

Parazoans have…

No distinct tissues

Parazoans

Sponges

What are the 2 diploblastic tissues types?

Endoderm and Ectoderm

What are the 3 diploblastic tissues types?

Endoderm, Mesoderm, Ectoderm

Diploblastic

Animals with two embryonic tissues Endoderm and Ectoderm

Triploblastic

Animals with three embryonic tissues

What structures do Endoderm tissues make?

GI tract

epithelium, anterior

pituitary, urogenital

epithelium

What structures do Ectoderm tissues make?

Nervous

system, posterior

pituitary, epidermis, nasal

and oral epithelium

What structures do Mesoderm tissues make?

Muscle,

Bone, Connective Tissue,

Urogenital Organs,

Dermis

Coelom

Internal fluid-filled body cavity

Coelomates

Have coelom

Acoelomates

Some don’t coelum

Pseudocoelomates

Some have mesoderm only lining ectoderm coelum

There are Diploblastic coelomates

False

Which of the following associations is INCORRECT?

Acoelomate: Earthworm

Protostome or Deuterostome

Blastopore turns into anus, then the organism is a deuterostome.

Gastrulation

Invagination of the blastula

Blastula

Hollow mass of cells

Blastocoel

Cavity of blastula

Induction happening

Some cells induce developmental changes in other cells. Leads to differentiation.

Diploblastic cleavage type

Radial symmetric

Triploblastic cleavage type

Bilaterally symmeetric

Dipoblastic organisms usually have something called a…

“blind gut” where food and junk go out

Coelum

Mesoderm-lined cavity aka an internal fluid-filled cavity

You can get specialized tissues, organs, etc. without a Coelom. However, why is having coelom better?

Having that sac structure allows for things like circulation, digestion, respiration, etc.

Those without a coelom are able to produce organs like…

Reproductive organs, eyespots, digestive tract.

Coelomic cavity is the cavity between the _____ and ____ layer. Dervived from the mesoderm

Parietal; Visceral

Name the benefits of the coelom

1. Diffusion of gases and nutrients

2. Flexibility

3. Cushion from harm

Pseudocoelomate is NOT a _____ group

Monophyletic. It is polyphyletic

Pseudocoelomate is any _____ animal with a three-layered body and a pseudocoel.

Invertebrate

Proto

Mouth

Deutro

Second

Stome

Mouth

Opisthokonta

Includes fungi, choanoflagellates, and animals

Characteristics of Porifera

• Cellular level of organisms

• Larvae are free-swimming, adults are sessile

• Asymmetric for most part

• reproduction

  • asexual - bud/gemmules

  • sexual - egg/sperm

Ostia

Small, water in

Oscula

Large, water out

The sponges belong to which of the following

groups?

I. Porifera

II. Opisthokonta

III.Parazoa

I, II, & III

Monoecious

“One house” male and female parts on same individual. Most common reproduction type for sponge.

Dioecious

“two houses” an individual is one of two sexes

Parenchymula

Free-swimming larva of sponges

What are the flagellated cells lining the sponge’s interior cavity?

Choanocytes

What is the main role of archaeocytes?

They digest food from choanocytes, move through the mesohyl, and can differentiate into other cells (sclerocytes, spongocytes, collencytes).

What are the three types of sponge canal systems?

Asconoid (simple), Syconoid (folded walls), Leuconoid (most complex, largest body size).

Which sponge canal system is the most complex?

Leuconoid

Do we use canal system type to classify sponges?

No, spicules are used for classification.

What are spicules made of?

Calcium carbonate or silica (sometimes bound with spongin).

What are the three “tissue-like” layers of sponges?

Pinacoderm (outer), Mesohyl (middle), Choanoderm (inner).

What are key traits of Calcarea?

Calcium carbonate spicules; includes asconoid and syconoid forms.

What are key traits of Demospongiae?

~80% of all sponges; leuconoid body plan; spongin (collagen) present.

What are key traits of Hexactinellida (Glass sponges)?

Silica skeleton, six-rayed spicules, syncytial body (trabecular reticulum).

What are key traits of Homoscleromorpha?

Simple siliceous spicules (or none); all spicules same size; thin encrusting body form.

Are cnidarians and ctenophores diploblastic or triploblastic?

Diploblastic (endoderm + ectoderm).

What kind of symmetry do cnidarians and ctenophores have?

Radial or rotational symmetry.

Do radiate animals have brains?

No, they have nerve nets (no centralized brain).

What is the specialized stinging cell unique to cnidarians?

Nematocyst

What are ctenes?

Comb-like plates of fused cilia used for movement.

What are colloblasts?

Adhesive “glue” cells unique to ctenophores.

Do ctenophores have nematocysts?

No (they lack them).

What type of gut do ctenophores have?

Through gut (mouth + anus).

What organ helps ctenophores maintain equilibrium?

Statocyst

Are ctenophores monoecious or dioecious?

Monoecious (hermaphroditic).