Biology Exam 4 Study Guide (complete early)

Animalia

Animals are eukaryotic, multicellular, heterotrophic organisms belonging to the kingdom ____

Ediacaran Period

The first animals evolved about 570 mya during the ___

Cambrian Period

Majority of animal phyla evolved during the ____ (540-485 mya)

Silurian Period

Based on fossil record, first animals (arthropods) moved onto land during the ______ (443-416 mya)

Devonian Period

First vertebrates moved onto land during the _____ (416-358 mya)

choanoflagellates,

Closest relatives of animals are thought to be ____, which colonial, heterotrophic protists

choanocytes

Choanoflagellates are morphologically similar to special cells in sponges called ____

Morula

Blastula

Upon formation of a zygote rapid cell division forms a ball of cells called a ____

Morula hollows out to form a ____

Basement Membrane

Convergent in other groups, animals in particular have a _____ in their extracellular matrix

Parazoans

The first major branching point in animals is determined by the presence or absence of complex tissues

• (sponges) have specialized cells, but these do not interact to form tissues

eumetazoan

All animals that are not parazoans belong to the _____, which have distinct tissues that perform specific functions

connective, muscle, nervous, and epithelial

Four basic tissue types found in animals are:

Connective tissue

supports, binds, or separates other tissues/organ systems

• May be highly specialized, forming structure such as bone and cartilage

Muscle tissue

contains protein filaments that slide past one another allowing for movement

• Include many specialized types and are necessary for the function of many organ systems

Nervous tissues

allow animals to respond to stimuli and maintain homeostasis

• Rely on the transmission of electrical signals to conduct information

Epithelial tissues

line outer and inner surfaces of organs and other tissue types and allow for absorption, secretion, protection, and other functions

gastrula

Cell layers are formed when the blastula folds in on itself, forming the ___

primary germ layers

endoderm, ectoderm, mesoderm

The gastrula may be composed of two, or three tissue layers called _____

• The three layers are: ___, ____, and, ___

endoderm

____ forms the inner- most layer of the gastrula

Epithelial tissues are primarily formed from the ___ (same word)

mesoderm

____ forms between the endoderm and the ectoderm in the gastrula

• Many connective tissues are formed from the mesoderm

Ectoderm

___ is the outermost layer of the gastrula

• Forms nervous tissue, as well as the outer epithelial tissues (skin)

radiata

have two germ layers (lack mesoderm)

-include most animals with radial symmetry

bilateria

have all three germ layers

The majority of animals belong to the ___(same word) , which are characterized by bilateral symmetry

cephalization

Bilaterally symmetrical animals exhibit ____, meaning sensory structures are concentrated in thehead

blastopore

During gastrulation, a hole is formed called the ___

Protostomes

the first opening of the tube forms the mouth

Deuterostomes

the first opening of the tube forms the anus

coelomates, pseudocoelomates, and acoelomates

There are three informal groups based on body cavity arrangement:

Coelomates

__ have a body cavity called a coelom with a complete mesoderm lining

• Allows organs to be attached in a particular order

Pseudocoelomates

__ have an incomplete mesoderm lining, which does not allow for arrangement of organs in cavity with same complexity

Acoelomates

__ lack any cavity at all, having semi solid mesodermal tissues between the gut and the body wall

complete and incomplete digestive tracts

The eumetazoans have a range of digestive tracts, broadly broken into ___ and ___

incomplete digestive tract

gastrovascular cavity

___ there is a single opening by through which food is taken, and waste expelled

Digestion occurs in the ____

complete digestive tract

__ food passes in one direction; from the mouth, to the anus

• More efficient in nutrient extraction

Indirect development

Direct development

__ involves distinct lifestyle phases, where a larva undergoes metamorphosis to adulthood

__ does not involve metamorphosis

phylum porifera

Sponges belong to the __

Spicules

are structural elements that help deter predators

Desmospongiae (sponge class)

__ is the largest class, 76.2 % of species

Hexactinellidiae

__ are referred to as the glass sponges and are characterized by their distinct, silica spicules

Cnidaria

Sea anemones, coral, and jellyfish belong to the phylum __

cnidocytes

Tentacles contain __which contain tiny harpoons that sting prey and predators alike

Anthozoans

__are the most diverse group including more that 6,000 species and include sea anemones, hard and soft coral, and gorgonians

• They are often sessile, colonial polyps that form elaborate calcium carbonate structures

Platyhelminthes

Some of the simplest bilaterians are the flatworms, which belong to the phylum __

Rhabditophora

The class___ is the most species rich group of flatworms

• Characterized by the presence of rhabdites, rodlike structures that secrete mucus for defense and terrestrial locomotion

Nematoda

Roundworms belong to the phylum __

• have a complete digestive tract enclosed by a pseudocoelom

stylet

amphids

The mouth often includes a hardened structure called a __ , used in predation/parasitism

Found near the head are sensory structures called __

Annelida

Segmented worms belong to the phylum __

dates back to the Cambrian Period

The oldest putative annelid fossil __

well defined segments and a well developed coelom

setae

Annelids are characterized by __

Locomotion is performed by wave like contractions of segments aided by __ which are hair-like projections along the body

Clitellates, and Polychaetes

Traditionally (Major Annelids) placed into one of two, major groups:

clitellum

Clitellates are the class of annelid worms characterized by having a __ , important in reproduction

• Includes earthworms and leeches

Polychaetes

parapodia

Called bristle worms, __ are characterized by __, fleshy vascularized protrusions used in locomotion and respiration

Mollusca

The phylum __ includes over 85,000 extant species, including organisms such as clams, oysters, snails, and octopuses

shell

conchiolin

The generalized mollusk is characterized by a __ that is composed of __, a protein hardened by calcium carbonate

mantel

mantel cavity

The shell sits atop the __, which secretes the conchiolin to form the shell

• Some organ systems may lie within a fold in the mantel called the __

Foot

Mollusks are also typically characterized by a muscular __, which is primarily used for locomotion

Radula

Mollusks are also characterized by a rasping structure called a __which is used in feeding

Love Dart

Mollusks reproduce sexually via external fertilization, though some terrestrial mollusks (snails and slugs) may use a calcareous structure called a __ for internal fertilization

Polyplacophora

Chitons belong to the class ___ and are characterized by their segmented shell, arranged in overlapping plates

• Most are herbivores, using their radula to scrape algae from rocks

Bivalvia

The class __ includes oysters, clams, mussels, cockles, and scallops

• Characterized by their distinct, hinged shells

• Primarily filter feeders

Gastrapoda

one-piece shells

torsion

Snails and slugs belong to the Class __ Characterized by their__, and by a developmental process known as __

Gastropoda

is the most diverse class of mollusks (think snail) with more than 50,000 species

• Inhabit a range of terrestrial and aquatic habitats

• They include the only terrestrial mollusks

Cephalopoda

Perhaps the most remarkable group of mollusks is the class ___ which includes squid, octopus, cuttlefish, and nautilus

by their well developed heads, and by their tentacles

beak (think octopus)

Cephalopods are characterized by their ___, and ___

Instead of a radula, have a hard, chitinous __

chromatophores

Many cephalopods have densely packed ___, or skin cells that can change color

Arthropoda

In protostomes the first opening formed in gastrulation becomes the mouth

• Includes the Platyhelminthes, Annelida, Nematoda, Mollusca, and __

most species rich phylum

Arthropods belong to the phylum Arthropoda

• It constitutes the __ BY FAR with more than 1,000,000 described species

exoskeleton

secreted by the epidermis

chitin

A distinguishing feature of arthropods is their __

The arthropod exoskeleton is __ forming the cuticle

The cuticle of arthropods is composed of a protein called __

jointed appendages

tagmata

Arthropods have segmented bodies, with __

Segments are fused to form specialized portions of the body called __

ecdysis

Exoskeletons limit range of motion somewhat

• Restrict growth, and so must be shed occasionally by __

hemolymph (a blood equivalent) (THINK)

Arthropods have a true coelom

• They have an open circulatory, where the heart swishes ___ through the body

compound eyes

ommatidia

Exoskeletons make tactile sensory difficult, but remedied by hair-like projections allowing them to sense their environment

• Most have __ composed of dozens- thousands of independent units called__

indirect development

Many arthropods undergo ___ characterized by distinct lifestyle stages

complete, or incomplete metamorphosis

Among insects, species may undergo __

arthropods from the late Silurian Period

The first animal fossils on land were __

Some hypotheses explaining this gigantism :

include higher oxygen levels at the time, and/or a lack of aerial predators

Trilobita, Chelicerata, Myriapoda, Crustacea, and Hexapoda

Arthropoda is divided into 5subphyla:

Trilobita

is an extinct subphyla representing some of the oldest known arthropods

• Well represented in the fossil record by the Cambrian Period, more than 17,000 species have been described

Permian Mass Extinction

The final order of trilobites (Proetida) went extinct during the ___

Chelicerata

__ is the arthropod group which includes arachnids, horseshoe crabs, and sea spiders

• More than 77,000 described species

chelicerae

A major feature of this group are their prominent mouthparts called : (Features of Chelicerata)

• Members of this group have two distinct tagmata

Book lungs

By far the most diverse chelicerates, arachnids include spiders and scorpions, among others

• Have well developed respiratory organs called __

Myriapoda

Millipedes and centipedes belong to the subphylum __

long segmented bodies, with every segment bearing walking legs

Myriapoda are characterized by their :

Crustacea

Shrimp, crab, lobsters and others belong to the subphylum __

Hexapoda

The subphylum __ includes insects as well as some other groups such as springtails

• They are the most species rich group within the most species rich phylum

three pairs of legs attached to a central tagma called the thorax

• Also have paired antennae that serve in tactile and chemosensory

Members of Hexapoda are defined by their : (Think Ants)

Insecta

Insects belong to the class __, and are the lion’s share of Earth’s animal diversity

have evolved powered flight

Insects were the first animals to ….

eusociality (Think Ants)

Many insects have developed complex social structures termed __

• are able to exploit resources very efficiently, and divide labor

Angiosperms

Many insect species have developed close relationships with __

Echinodermata, and Chordata

Far less species rich than the protostomes, deuterostomes nonetheless are prominent in many aspects of our lives

• Includes two phyla:

Echinodermata

Sea stars, sea urchins, and sand dollars all belong to the phylum ___, among others

penta-radial symmetry

The echinoderms are characterized by their five- part body-plans called __

water vascular system

echinoderm Posses a unique hydraulic system used in locomotion, food and waste transportation, and respiration called the __

Tube Feet

Many echinoderms are mobile predators

• Sport thousands of structures on the ventral surface caused __

Moved via hydraulic pressure, tube feet are used in feeding, locomotion, and respiration

Crinozoa, Asterozoa, and Echinozoa

There are three extant groups of echinoderms:

Crinozoanas

sessile filter feeders,

mouths on the dorsal surface

__ are commonly called sea lilies or crinoids

Most are __ with their __

Asterzoa

The most species rich class of echinoderms, the __ includes typical sea stars and brittle stars

Echinozoans

__ include sea cumbers, sand dollars, and sea urchins

• Mostly mobile herbivores and detritivores