chapter 34

zoology - dr. tenneson - ch. 34

what phylum is subphylum craniata in?

phylum chordata

are vertebrates bilaterally or radially symmetrical?

bilateral

what are the 2 groups of invertebrate deuterostomes?

urochordates & cephalochordates

what is unique to the vertebrate group?

embryonic tissue/neutral crest

what are the 4 chordate characteristics?

notochord, dorsal hollow nerve chord, muscular post-anal tail, pharyngeal slits

the 4 chordate characteristics are


1. notochord
2. dorsal hollow nerve chord
3. muscular post-anal tail
4. pharyngeal slits

\
* where is the notochord located?
* what is the notochord made of?
* where is the dorsal nerve chord located?

inferior to dorsal nerve chord. cartilage. back

what is the purpose of the notochord?

allow muscles to contract without body getting shorter

annelids/arthropods & chordates have nerve chords located in different places. which has a dorsal nerve chord?

chordate

the _____ _____ consists of bilateral bands of cells near the margins of the embryonic folds that form the neural tube. the cells give rise to some of the anatomical structures unique to vertebrates, including some of the bones & cartilage of the skull.

* forms from the gastrula → neurula
* a ridge with a valley forms a tube
* green cells: found only in chordates. start around valley, then migrate
* form facial bones & jaw

neural crest

the neural crest consists of bilateral bands of cells near the margins of the embryonic folds that form the neural tube. the cells give rise to some of the anatomical structures unique to vertebrates, including some of the bones & cartilage of the _____.

* forms from the gastrula → neurula
* a ridge with a valley forms a tube
* green cells: found only in chordates. start around valley, then migrate
* form facial bones & jaw

skull

early chordates may have resembled _____

lancelets

what do hox genes do?

organize the vertebrate brain are expressed in the lancelet’s simple nerve cord tip

what animals are in subphylum urochordata?

tunicates (sea squirts)

animals in subphylum urochordata are enclosed in a tunic of _____-like carbohydrate

cellulose

what do the larvae of subphylum urochordata look like?

tadpoles

how do tunicates move?

draw water in & pump water out

tunicate larvae settle & attach to _____ & turn sponge-like

substrates

tunicate larvae settle & attach to substrates & turn _____-like

sponge

what animals are in subphylum cephalochordata?

lancelets

are animals in subphylum cephalochordata segmented or unsegmented?

segmented

are animals in subphylum cephalochordata suspension feeders or filter feeders?

filter feeders

how do animals in subphylum cephalochordata trap food?

in mucous

do lancelets burrow?

yes

* lancelets burrow
* they keep their _____ out of the ground
* their _____ expels food waste
* their _____ is sticky to trap nutrients

head. anus. throat

what are the 4 characteristics of clade vertebrata?

neural crest, cephalization, vertebral column, closed circulatory system

what does “craniates” mean?

has a cranium

The Origins of Craniates:

* fossils from the _____

cambrian

The Origins of Craniates:

* what’s the oldest craniate?

Haikouella

The Origins of Craniates:

* well-formed brain, eyes, & muscular segments
* BUT no _____

skull

a Haikouella is a chordate but doesn’t have a _____

cranium

true craniates are chordates that don’t have a _____

cranium

what are the 2 superclasses in subphylum craniata? what does each mean?

supercalss agnatha (jawless) & superclass gnathostomata (jaws)

what animals are in class myxini?

hagfish

are hagfish scavengers?

yes

hagfish have slime _____

glands

hagfish secrete _____

mucous

_____ are the only craniate osmoconformer.

* what does “osmoconformer” mean?

hagfish. inside conforms to sea water

do hagfish have vertebrae?

no

are hagfish a craniate or a vertebrate?

craniate

do hagfish have true jaws?

no (they have jaws but not true jaws)

do hagfish have top/bottom or left/right jaws?

left/right

what animal has “knotting” behavior?

hagfish

are animals in class cephalospidomorphi true vertebrates?

yes

animals in class cephalospidomorphi feed on _____

blood

animals in class cephalospidomorphi have larvae similar to _____

lancelet

animals in class cephalospidomorphi have partially developed _____

vertebrae

animals in class _____ can suction to rocks & live in high velocity water

cephalospidomorphi

are conodonts living or extinct?

extinct

do conodonts have jaws, or are they jawless fish?

jawless

what are the oldest vertebrates?

conodonts

where do conodonts have teeth?

in throat

are animals in class ostractodermi alive or extinct?

extinct

are animals in class ostractodermi suspension feeders or filter feeders?

filter feeders

are animals in class ostractodermi armored or soft-skinned?

armored

what is the purpose of the armor on animals in class ostractodermi?

protection against giant invertebrates who were predatory and also lived in water

what 2 animals are in class ostractodermi?

pterapsis & pharyngolepsis (neck covered by bones in skin, jawless, filter feeder)

animals in class ostractodermi had an _____ skeleton

embryological

what were the 3 steps of jaw evolution for animals in class ostractodermi?

jawless fish had gill slits for respiration. skeletal rods moved forward, and there were bones for jaw support. additional support/thickening bones behind the jaw

do animals in superclass gnathostomata have jaws?

yes

are animals in superclass gnathostomata terrestrial or aquatic?

aquatic

do animals in superclass gnathostomata have scales?

yes

are animals in class placodermi alive or extinct?

extinct

are animals in class placodermi armored?

yes

animals in class placodermi have paired _____

fins

animals in class placodermi have _____ fins

paired

what animals are in class chondrichthyes? (4)

sharks, skates, rays, ratfish

animals in class chondrichthyes:

* _____ skeleton

cartilage

animals in class chondrichthyes:

* strong _____

jaws

animals in class chondrichthyes:

* _____ fins

paired

animals in class chondrichthyes:

* ancestors appeared to have bony _____

skeletons

animals in class chondrichthyes:

* where does their buoyancy come from?

oil in the liver

animals in class chondrichthyes:

* usually constant _____

swimmers

animals in class chondrichthyes:

* largest fish is the _____ shark

whale

animals in class chondrichthyes:

* which of the following describes them? (more than 1)
* suspension feeders
* filter feeders
* herbivores
* carnivores

carnivores, filter feeders

animals in class chondrichthyes:

* their teeth are modified _____

scales

animals in class _____:

* their teeth are modified scales. their scales are backwards tooth-shaped & rough. shark teeth are big placoid scales

chondrichthyes

animals in class chondrichthyes:

* what type of digestive system do they have?

spiral valve

animals in class chondrichthyes:

* _____ sense organs (detect prey & for navigation)

electric

animals in class chondrichthyes:

* what is the purpose of their lateral line system?

water vibration system. pits on sides allow to feel vibrations of prey

animals in class chondrichthyes:

* sexual or asexual?
* internal or external fertilization?

sexual. internal fertilization

animals in class chondrichthyes:

* do they lay eggs or do they have a live birth?

both

cartilaginous fish characteristics:

* what does negative buoyant mean? how does this relate to sharks?

body density is greater than sea water. sharks swim constantly to maintain depth so they don’t sink.

cartilaginous fish characteristics:

* what is a spiracle?

canal to the throat. alternate water pathway for when mouth is blocked

cartilaginous fish characteristics:

* how many dorsal fins are there?

2

cartilaginous fish characteristics:

* where are the gills located?

under the slits

cartilaginous fish characteristics:

* the pectoral fin has an upward force on it because of _____

angle

cartilaginous fish characteristics:

* the angle of the nose & tail determine _____

direction

cartilaginous fish characteristics:

* when the tail is pushed down, the nose goes ____

up

what are the 4 sharks that are most dangerous to humans?

bull shark, tiger shark, white shark, oceanic whitetip

skates & rays:

* _____ _____ are greatly enlarged to form “wings”

pectoral fins

skates & rays:

* _____ _____ is reduced/absent

tail fin

how do skates & rays differ from sharks? (2 points)

have few scales & adapted for feeding on bottom-dwelling animals

technically _____ are a type of _____

\
* skates, ray
* rays, skate

skates, ray

skates vs rays

* which has live birth & which lays eggs?

rays have live birth & skates lay eggs

skates vs rays

* which have large teeth & which have small teeth?

rays have large teeth & skates have small teeth

rays are viviparous. what does this mean?

they give live birth

skates are oviparous. what does this mean?

they lay eggs

do rays or skates involve mermaids purse?

skates

chimeras aka “_____”

ratfish

_____ are deep water soft bottom dwellers

chimeras