Anatomy 241 Exam I Chapter 2

Front 1

organisms with bilaterial symmetry

Back 1

bilateria

Front 2

organisms with a fluid filled body cavity

Back 2

coelomates

Front 3

"first mouth" Animals which develop a mouth from the blastopore

Back 3

protostomes

Front 4

"second mouth" Animals which develop a mouth from the opposite end of the digestive tract.

Back 4

deuterostomes

Front 5

What are the four fundamental features that chordates share?

Back 5

dorsal hollow nerve cord
notochord
postanal tail
pharyngeal slits

Front 6

The notochord serves as an "_" and flexes laterally from side to side.

Back 6

elastic rod

Front 7

the notochord with a fluid core may be classified as a _

Back 7

hydrostatic organ

Front 8

the pharynx, part of the digestive tract, is located just _ to the mouth

Back 8

posterior

Front 9

pharyngeal slits likely first evolved to aid in _ and later with _

Back 9

feeding, respiration

Front 10

cilia that line the pharynx establish the _ of water and move _ into the digestive tract

Back 10

current, food laden mucus

Front 11

_ are an assortment of invertebrates whose structure and design may represent chordates at their origins

Back 11

protochordates

Front 12

the three protochordates:

Back 12

Hemichordata
Urochordata
Cephalochordata

Front 13

Defination of
1. Hemichordata
2. Urochordata
3. Cephalochordata

Back 13

1.half chordates
2.tail backstring
3.head chordate

Front 14

Hemichordates are marine worms that appear to link _ and _

they lack a _ and _

Back 14

Echinoderms, Chordates, notochord, tail

Front 15

hemichordates have a structural _ which was thought related to the notochord, but has failed genetic comparisions.

Back 15

stomochord

Front 16

Hemichordates exist within 1 of 2 taxonomic groups

Back 16

Enteropneusta
Pterobranchs

Front 17

Definations:
1. enteropneusta
2. pterobranchs

Back 17

1. burrowing animals
2. sessile animals

Front 18

enteropneusta "_ worms" are marine burrowing worms
Their body is divided into three regions:

Back 18

acorn
1. proboscis
2. collar
3. trunk

Front 19

each region of enteropneusta has its own coelom (3)

Back 19

protocoel, mesocoel, metacoel

Front 20

The first "true" members of the phylum chordata and at some point of their life cycle they generally show all four of the characteristics common to chordates.

Back 20

Urochordata

Front 21

Urochordates may be divided into 3 taxonomic groups:
_ - sessile
_ and _ - pelagic (plankton)

Back 21

Ascidiacea
Larvacea & Thaliacea

Front 22

Ascidians "_" do not greately resemble what we think of as chordates, but the _ state exhibits all 4 chordate characteristics.

Back 22

sea squirts, larval

Front 23

Ascidians often refered to as "_" because the adult forms are covered by a covering called a tunic

Back 23

tunicates

Front 24

Amphioxus is a _ that we studied in lab

Back 24

cephalochordata

Front 25

cephalochordata, anatomically simple animals that are designed to be suspension feeders based on their _ (much like _)

Back 25

pharyngeal filtering aparatus, protochordates

Front 26

The oldest known member of the cephalochordate is the _ which is an extant version of the _ (Amphioxus)

Back 26

Pikala, Branchiostoma

Front 27

Amphioxus has muscles arranged in segments (_) which are seperated from one another by partitions (_)

Back 27

myomeres, myosepta

Front 28

The _ and _ contraction of these muscles propels amphioxus through the water and aides in burrowing into the sediment.

Back 28

orderly, sequential

Front 29

In the digestive system of the Amphioxus food first moves into the _ before entering the pharynx.

Back 29

oral hood

Front 30

_ project outward from the oral hood and prevent large particles from entering

Back 30

Buccal cirri

Front 31

_ tracts inside the oral hood give the impression of rotation and are collectively termed the "_"

Back 31

ciliated, wheel organ

Front 32

_ - one of the dorsal tracts in the vestibule (similar to the wheel organ)

Back 32

Hatschek's pit

Front 33

some propose that the Hatschek's Pit may be the forerunner to the vertebrate _ gland.

Back 33

pituitary

Front 34

The trapping of food (Amphioxus) occurs in a _ - _ direction.

Back 34

ventral - dorsal

Front 35

the _ secretes mucus to trap food

Back 35

endostyle

Front 36

_ move the mucus dorsally

Back 36

cillia

Front 37

the food trapped in the mucus is directed to the _ and then into the digestive tract.

Back 37

epipharyngeal

Front 38

The posterior wall of the oral hood is defined by a diaphragm called the _

Back 38

velum

Front 39

sensory structures (_) sense and sort material before it passes through the opening of the velum and into the pharynx

Back 39

velar tentacles

Front 40

water that enters the pharynx passes through the pharyngeal slits and exits the body via the _ in the posterior portion of the _

Back 40

atriopore, atrium

Front 41

the midgut diverticulum (cecum) is thought to be the forerunner of the liver due to: (2)

Back 41

anatomical location
blood supply

Front 42

the hepatic diverticulum may also be related to the _ because cells in the wall secrete digestive enzymes.

Back 42

pancreas

Front 43

The digestive (GI tract) of the anphioxus includes: (3)

Back 43

midgut
ileocolic ring
hindgut

Front 44

Waste materials exit the body via the

Back 44

anus

Front 45

The amphioxus has _ heart

Back 45

no

Front 46

the task of pumping blood for the amphioxus is distributed among several _

Back 46

blood vessels

Front 47

Blood circulation is laid out on the same general pattern as that of the _:
_ carries blood anteriorly
_ carries blood posteriorly

Back 47

vertebrates, ventral aorta, dorsal aorta

Front 48

amphioxus exchange gasses via _

Back 48

diffusion

Front 49

in the amphioxus gases are exchanged between the water and vessels of the _ within the pharyngeal bars

Back 49

pharyngeal complexes of blood vessels