Biodiversity: Unikonta, introduction to animals, porifera and cnidaria

animals

multicellular heterotrophic eukaryotes organisms that lack cell walls

what changes occur as animals diversify?

changes in morphology and development

why can diversity occur?

duplication mutations of hox genes

what are the four groups of animals?

non-bilaterian lineages, two protostome groups (lophotrochozoa and ecdysozoa) and deuterostomes

sessile

An organism that does not move. It remains attached to one place.

Asconoids

simplest sponge body plan, tubular shape

syconoids

tubular like asconoids, body wall folded forming radial canals

Leuconoids

bath sponges, these have the most complex morphology of sponges

Porifera (sponges)

Simplest animals; lack true tissues & symmetry

what are synapomorphies of animals

multicellularity, heterotrophy, they move under their own power

all animals except sponges have..

nerve and muscle cells

all animals have..

tissues and epithelium

diploblasts

animals whose embryos have two types of tissues

what are the two types of tissues of diploblasts

ectoderm and endoderm

Triploblasts

animals whose embryos have three germ layers

What are the layers of triploblasts

ectoderm, endoderm, mesoderm

Ectoderm gives rise to

skin and nervous system

Endoderm gives rise to

lining of digestive tract

Mesoderm gives rise to

the circulatory system, muscle, and internal structures such as bone and most organs

what animals are diploblastic?

most cnidarians (jellies, corals etc.)

why was the evolution of mesoderm important

gave rise to first complex muscle tissue

Cnidaria include?

jellyfish, corals and sea pens

Ctenophora are?

comb jellies

which animals have nerve cells organized into a nerve net?

cnidarians and ctenophores

Do sponges have neurons?

no

CNS

central nervous system

Organisms with nerve nets have what kind of symmetry

radial symmetry

Organisms with CNS tend to have what kind of symmetry?

bilateral symmetry

Most sponges are

asymmetrical

radial symmetry

at least two planes of symmetry

bilateral symmetry

a single plane of symmetry and long narrow bodies

cnidaria

corals, radial symmetry

what is evolution diversification based on?

innovative ways of sensing the environment, feeding, movement

what group are animals?

monophyletic

what three traits do all animals share?

multicellularity, heterotrophy, and move under their own power

All animals except sponges have

neurons and muscle cells

Do sponges have tissues?

(sponges) do not have true tissues (muscle and nervous)

true or false: animals are the only multicellular heterotrophs that ingest their food

true

What phylum do sponges belong to?

Porifera

Who is J.B.S. Haldane?

geneticist and evolutionary biologist, founders of modern synthesis of evolutionary biology

what are the four aspects of the body plan of an animal?

number of embryonic tissue layers, type of body symmetry, presence or absence of fluid filled body cavity, embryo development

Cephalization

development of head region where structures for feeding, sensing the environment and processing info are

true or false: all animals have tissue

true except sponges

tissues

integrated structural and functional units of cells

true or false: almost all animals have epithelium

true except sponges

epithelium

a layer of tightly joined cells that covers the body surface

diploblasts

animals whose embryos have two types of tissue (germ layers), ectoderm and endoderm

ectoderm vs endoderm

outside skin and inner skin

triploblasts

animals whose embryos have three types of tissue

Mesoderm

middle germ layer; develops into muscles, and much of the circulatory, reproductive, and excretory systems

most cnidarians are

diploblastic

except cnidarians, all other animals are

triploblastic

why was the evolution of mesoderm important

rise to first complex muscle tissue used in movement

what animals have a nerve net?

what about other animals?

cnidarians and ctenophores

what kind of symmetry do organisms with a nerve net have?

radial symmetry

what kind of symmetry do organisms with CNS have?

bilateral symmetry

what is a basic feature of a multicellular body?

the presence or absence of a plane of symmetry

Most sponges are

asymmetrical

Animals with radial symmetry

Cnidarians

bilateral symmetry allowed for?

cephalization

cerebral ganglion (brain)

Large mass of neurons that is responsible for sending and receiving information to and from the body

coelom

fluid-filled body cavity lined with mesoderm

acoelomates

triploblasts that do not have a coelom, no enclosed body cavity

coelomates

Triploblasts with a coelom, have an enclosed body cavity completely lined with mesoderm

Where does the coelom form?

Within the mesoderm and thus is lined on both sides with cells from the mesoderm

hydrostatic skeleton

a fluid-filled internal cavity surrounded by muscle tissue

what does the coelom act as?

an efficient hydrostatic skeleton

true or false: sponges are benthic

true

Bilateria is divided into

protostomes and deuterostomes

Protostomes

mouth develops before the anus

lophotrochozoa

extending by size of skeleton and includes mollusks and the annelids

Ecdysozoa

growth via shedding external skeletons and expanding their bodies

vertebrates

animals with skulls and backbones

invertebrates

animals not vertebrates

Deuerostomes

anus develops before the mouth

What part of the earthworm do you need to know?

Clitellum

Choanoflagellates

closest living relatives of animals

benthic

living at the bottom of aquatic environments

What are sponges made of?

a system of tubes and pores that create channels for water currents

do sponges have specialized cell types?

yes and some have epithelial tissues

Spicules

Found in sponges, these consist of inorganic materials and support the animal

What kind of feeders are sponges?

suspension feeders, filter water in their body and filter the food

when are sponges sessile and motile?

adult sponges are sessile, larvae are motile

what is the reproduction of sponges?

asexual most times, rarely sexual production

Key facts about sponges

water flows into body via pores and through the central cavity spongocoel and out the excretory opening (osculum)

can sponges be both male and female?

yes they are squential hermaphrodites

sequential hermaphrodites

each individual produces male and female gametes in sequence

choanocytes

flagellated collar cells, generate a water current through the sponge and ingest suspended food

amoebocytes

Cells that move using pseudopods and perform different functions in different animals

what are they asexual buds that amoebocytes can produce?

gemmules

true or false: all coelomates are bilaterally symmetric and have three embryonic tissue layers

true: except for adult echinoderms

what groups can bilateria be divided into?

protostomes and deuterostomes

Protostome

an animal whose mouth is formed before the anus

Deuterostomes

anus develops before the mouth, and pockets of mesoderm pinch off to form the coelom

what organism is most closely related to animals?

choanoflagellates

endoparasite

parasite living on the inside of its host

Ectoparasites

Parasites that feed on external surface of host.

predator

An animal that hunts other animals for food

prey

An organism that is killed and eaten by another organism