Protists and Animal Evolution

Cilia

microscopic hairs that help the Paramecium move

Pseudopod

"false foot"; used by the Amoeba for movement and engulf food

Flagella

tail-like structure used by the Euglena for movement

Euglena

Unicellular organism; autotroph and heterotroph

Amoeba

Animal-like protists; they have pseudopods (false feet)

Paramecium

most complex and specialized protist that moves by cilia

Autotroph

An organism that makes its own food

Heterotroph

An organism that cannot make its own food.

Eukaryotic

A cell that has a true nucleus and other membrane-bound organelles.

Prokaryotic

An organism whose cells do not have an enclosed nucleus, such as bacteria.

animal-like

protists that are heterotrophs; called protozoans

plant-like

protists that are autotrophs

fungus-like

protists that are decomposers

ciliates

protozoans; use cilia for movement and feeding; example: Paramecium

Phylum Ciliaphora

diatoms

phytoplankton, secrete thin cell walls of silica called a frustule; non-motile; produce 20-50% of the world's oxygen

dinoflagellates

have two flagella and thick cell walls- plate-like; unicellular; responsible for red tides; some species are bioluminescent

Fire Algae

Phylum Pyrrophyta

Red Algae

contains red pigment; multicellular; called seaweed; some found in foods

Brown Algae

contains brown pigment; multicellular; an example Kelp

Green Algae

unicellular, colonial, filamentous, or multicellular; example: Volvox, Spirogyra

plasmodial slime molds

many flagellated cells form a multinucleated, amoeboid mass called a plasmodium; reproduce similar to fungi by forming sporangia

water mold

fungus-like; produce filaments called hyphae; sexual and asexual reproduction; dead decaying matter in aquatic environments, some are plant parasites

protists

kingdom of odds & ends; unicellular or multicellular organisms found in moist or wet environments

eyespot

light-sensitive area that helps a Euglena navigate toward light

Are organisms in Kingdom Protista prokaryotic or eukaryotic?

eukaryotic

contractile vacuole

The structure that collects and pumps out excess water from protozoan cells

pellicle

A firm, flexible coating outside the cell membrane that helps a protozoan keep its shape

diatomaceous earth

a soft, fine, deposit that is composed mainly of the skeletons of diatoms

Endosymbiosis

theory in which the engulfing of one prokaryote by another prokaryote gave rise to organelles such as chloroplasts and mitochondria

Dinoflagellates

Group of protists that form "blooms", can be toxic, make up phytoplankton, generally have two flagella

Euglenoids

A plant-like Protist that has some animal like characteristics (flagella, eyespot), have a distinctive covering called a pellicle

cellular slime molds

Have unicellular and multicellular life stages- spend most of their lives as separate single-celled amoeboid protists, but upon the release of a chemical signal, the individual cells aggregate into a great swarm

Zooplankton

small free-floating amoeboid protists such as radiolarians and foraminifera; many form a test as a hard outer covering; important in the fossil record

Flagellated Protozoans

member of a heterotrophic lineage of protists that have one or more flagella; some are disease causing such as Giardia, Trichomonas, Leishmania, and Trypanosoma

ciliated Protozoans

very commonly found protist that uses cilia to move and feed; also have a contractile vacuole; examples include paramecium and stentor

Apicomplexans

Group of protozoans that are all parasitic; non-motile; use apical complex to penetrate host cell and absorb nutrients; examples include Babesia , Toxoplasma, Cryptosporidium

Class Gastropoda

slugs & snails

Class Cephalopoda

squid & octopus

Class Bivalvia

oysters & clams

Class Chondrichthyes

cartilaginous fish (sharks, skates, rays)

Class Osteichthyes

bony fish- includes ray finned and lobe finned

Class Amphibia

frogs, toads, salamanders, caecilians

Class Reptilia

lizards, snakes, turtles, crocodilians

Class Aves

birds

Class Mammalia

have hair and mammary glands; most are endothermic; humans, cats, dogs, bats, whales.

Subphylum Prototheria- Monotreme

egg-laying mammal such as platypus and echidna

Subclass Theria- Marsupial

Mammals without placentas such as kangaroo, koala, opossum

Porifera

sponges

Cnidaria

jellyfish, corals, sea anemones

Platyhelminthes

flatworms

Arthropoda

jointed-legged invertebrates belong, including insects, arachnids, millipedes/centipedes, and crustaceans

Mollusca

(snails, clams, squids, octopuses) have a soft body that in many species is protected by a hard shell

Annelida

segmented worms such as the earthworm, bristle worms, and leeches

Nematoda

roundworms such as heartworms

Echinodermata

radially symmetrical marine invertebrates including e.g. starfish and sea urchins and sea cucumbers (bilateral as juveniles)

Chordata

animals with a notochord, a dorsal nerve cord, and pharyngeal gill slits

Subphylum Urochordata

tunicates (sea squirts)

Subphylum Cephalochordata

lancelets

Subphylum Vertebrata

fish, amphibians, reptiles, birds, mammals

Animal

Heterotrophic, multicellular, eukaryotes. They support their body tissue, move at one point in their life, usually reproduce sexually, and have similar stages of early development.

Chanoflagellates

Protists that formed colonies in the sea 570 million years ago that present-day animals might have evolved from. Multicellular.

Invertebrates

Animals without backbones. 95-99 percent of animals are this.

Exoskeletons

Hard or tough outer coverings that provide a frame work of support for many invertebrates.

Molting

Process in which invertebrates shed the old exoskeleton and grow a new one.

Endoskeletons

Internal skeleton.

Vertebrate

An animal with and endoskeleton and a backbone.

Hermaphrodites

Produce both eggs and sperm in the same animal body. An animal that does this is the earthworm.

Zygote

Fertilized egg cell. Formed by a sperm penetrating the egg.

Internal Fertilization

Occurs when the sperm and egg com pine inside the animal's body.

External Fertilization

Occurs when the egg and sperm combine outside of the animals body. An example of an animal that does this are fish.

Budding

An offspring develops as a growth on the body of the parent.

Fragmentation

Parent breaks in to pieces, which can develop into an adult.

Regeneration

An adult organism can regenerate or regrow from a body part of sufficient size.

Parthenogenesis

A female organism produces eggs that can be developed without fertilization.

Blastula

Stage after the zygote in which the organism is a fluid filled ball of cells.

Gastrula

Stage after the blastula in which the organism is a two-layer sac with an opening at one end.

Endoderm

The inner layer of cells in the gastrula. These cells develop into the digestive organs and the lining of the digestive tract.

Ectoderm

The outer layer of cells in the gastrula. Cells in this continue to grow and become the nervous tissue and skin.

Mesoderm

Form between endoderm and ectoderm. Becomes muscle tissue and the circulatory, excretory, and respiratory systems.

Symmetry

Describes the similarity or balance among body structures of organisms.

Asymetry

Irregular in shape, no balance to the body tissues. An example is sponge.

Radial Symmetry

Can be divided along any plain through a central axis into equal halves. An example is a jellyfish. Have two embryonic cell layers - ectoderm, endoderm.

Bilateral Symmetry

Can be divided into mirror image halves along one plane through a center axis. An example is the hummingbird.

Anterior

Head end of animals with bilateral symmetry.

Posterior

Tail end of animals with bilateral symmetry.

Dorsal

Backside of animals with bilateral symmetry.

Ventral

The underside or belly of animals with bilateral symmetry.

Coelom

A type of fluid-filled cavity that has tissue formed from mesoderm that lines and encloses the organs.

Pseudocoelom

A fluid-filled body cavity that develops between the mesoderm and the endoderm. Lined only partially with mesoderm. Limits tissue, organ, and system development.

Acoelomates

Such as flat worms. Animals that do not have a coelom. Body plan is derived from ectoderm, endoderm, and mesoderm.

Protostomes

Mouth develops from the first opening in the gastrula. The outcome of each cell in the 8-cells stage cannot be altered.

Deuterostomes

Anus develops from the first opening in the gastrula. The outcome of each cell in the 8-cell stage can be altered. Each cell in the early embryo can give rise to a full organism.

Segmentation

The body plan is divided into segments.

Major animal adaptations

Development of tissues, symmetry, body cavity development, segmentation, and protosome vs deuterostomes.

Sponges

The only animals without tissue.

Tissue

Specialized groups of cells that perform a particular function.

Phylum Portifera

All are aquatic (mostly marine). Asexual reproduction by budding. Lack a nervous system. Specialized cells perform jobs in the body. Ex: sponges.

Phylum Cnidaria

Two basic body forms: Medusa and polyp. Some species have a life cycle that alternates between medusa and polyp. All are aquatic, most are marine. Ex: jellyfish, sea anemones, and corals.