Deuterosomes

Question 1

2 phyla of deuterosomes

Answer 1

1) Echinodermata

2) Chordata

Question 2

General features of deuterostomes (4)

Answer 2

1) Bilateral symmetry
2) Coeom
3) Radial cleavage
4) Blastopore

Question 3

Examples of Echinodermata

Answer 3

Starfish, sand dollars, sea urchins, sea lillies, sea cucumbers and brittle stars

Question 4

Do echinoderms or chordata share a common ancestor with humans?

Answer 4

Echinodermata

Question 5

Echinodermata exoskeleton is made out of (1)

Answer 5

CaCO3 (Calcium carbonate)

Question 6

Types of sexual reproduction in echinodermata

Answer 6

Contain sexual and asexual reproduction capabilities
Sexual: Reproduction
Asexual: shed leg to form new individual

Question 7

Holothioidea

Answer 7

Sea cucumbers

Important food in certain cultures

Question 8

3 sub-phylums of Chordata

Answer 8

1) Vertebrata
2) Cephalochordata
3) Urochordata

Question 9

Urochordata

Answer 9

Sea squirts

Question 10

Four common features of Chordates

Answer 10

1) Notochord
2) Pharyngeal slits
3) Dorsal, hollow nerve cord
4) Muscular, post-anal tail

Question 11

Where does the notochord develop from?

Answer 11

Mesoderm

Question 12

Placement of the notochord

Answer 12

Dorsal to the coelom

Beneath (but parallel to) the CNS

Question 13

Notochord features

Answer 13

Core of cells & fluid surrounded by fibrous sheath

Allows for locomotion through lateral undulation (tail movement like sperm)

Question 14

Who contains notochord and when?

Answer 14

Present in bony fish and terrestrial vertebrates

• present during embryonic development
• replaced by ventral column
• persists as nucleus pulposes in intervertebral disk

Question 15

Who and when contain Pharyngeal slits?

Answer 15

Terrestrial vertebrates (present in embryo, lost during embryogenesis)

Aquatic vertebrates (gills develop adjacent to pharyngeal slits; allow for water flow across gills)

Question 16

Location of the dorsal, hollow nerve cord

Answer 16

Lies above (superficial) to the gut

Question 17

What is the dorsal hollow nerve cord made out of?

Answer 17

fluid-filled neurocoel

Question 18

Muscular post-anal tail

Answer 18

• posterior elongation of the body beyond the anus

- consists of segmental musculature and the notochord

Question 19

Cephalochordata

Answer 19

Subphylum of Chordata
resemble earliest chordates
fossils in cambrian era 
Temperate and Tropical seas 
Anatomically simple 
Living: Brachiostoma - amphioxus

Question 20

Branchiostoma

Answer 20

Subphylum of chordata 
Possess all 4 chordate features in adult
Blade like body shape 
- Filter feed
- ciliated pharynx
- mucous nets across slits

Question 21

Systems in Cephalochordata

Answer 21

Digestive system
Circulatory system
“Brain” is not differentiated - cluster of cells

Question 22

How is the Chordate brain similar to human brain? (3)

Answer 22

Similar gene expression in human embryos compared to chordate

1) BF1
2) Otx
3) Hox3

Question 23

Urochordata

Answer 23

Subphylum of Chordata
All species are marine
Tunicates
Ex) Sea Squirts

Question 24

Which Chordate subphylum evolved alongside vertebrates and have a common ancestor?

Answer 24

Urochordates

Question 25

What are the three divisions of the CNS in chordates?

Answer 25

1) Sensory vesicle 2) Visceral ganglion 3) Nerve cord

Question 26

Sensory Vesicle

Answer 26

Part of chordate CNS Contains (2) 1) Ocellus 2) Otolith

Question 27

Ocellus

Answer 27

Photoreceptive organ

Question 28

Otolith

Answer 28

Gravity-sensitive structure

Question 29

Visceral ganglion (2)

Answer 29

Part of Chordate CNS 1) Sends nerve tracts to musculature 2) Receives sensory nerves from tail

Question 30

Nerve Cord

Answer 30

Part of Chordate CNS - Ciliated ependymal cells around neurocoel - move CSF through nerve chord - Same type of cells that humans have

Question 31

Ependymal cells

Answer 31

CNS cells which function to move cerebral spinal fluid (CSF) through nerve chord

Question 32

4 structures found in Chordate Larvae

Answer 32

1) Central Nervous system 2) Neural Crest Cells 3) Rudimentary Heart 4) Blood

Question 33

Craniata

Answer 33

- Chordates with heads (craniums) for movement and feeding

Question 34

What is the unique feature of Chordate Larvae

Answer 34

Presence of the neural crest | - population of cells that give rise to many structures (teeth, bone, neurons, etc.)

Question 35

Hagfish

Answer 35

``` Craniate, part of chordata Cartilaginous skull - not bony skull No jaw or vertebrae Notochord in adult All Marine Feed on detritus Produce mucus for defence ```

Question 36

Lampreys

Answer 36

Vertebrate, derived from craniates Cartilaginous skeleton Lack jaws, have rasping tongue/teeth Primitive vertebrae ENCLOSE vertebrae

Question 37

What was the most significant step towards selective feeding?

Answer 37

Development of jaws in Gnathostomes

Question 38

2 classes of Gnathostomes

Answer 38

1) Chondrichthyes (cartilagenous fish) | 2) Osteichthyes (bony fish)

Question 39

Chondrichthyes

Answer 39

``` Cartilaginous skeleton Sharks and rays cartilaginous skeleton replaces notochord Internal Fertilization Contain Placoid Scales Lack swim bladder ```

Question 40

Placoid scales (3)

Answer 40

1) Dentine and enamel 2) Surface denticles ("small teeth") 3) Develop in dermis (project through epidermis)

Question 41

What destinguishes between males and females in Chondrichthyes

Answer 41

Males: Claspers Females: Cloaca

Question 42

What allows Chondrichthyes eggs develop in harsh water environment

Answer 42

Oviparous: Tough, leathery egg cases

Question 43

How long is the dogfish (chondrichthyes) gestation period?

Answer 43

2 years

Question 44

Osteichthyes

Answer 44

``` Class Vertebrata Bony fish Predominantly bone scales (do not penetrate epidermis) Swim Bladder External fertilization ```

Question 45

2 subclasses of Osteichthyes

Answer 45

1) Actinopterygii - ray finned fish (trout) | 2) Sarcopterygii - lobe-finned fish (lungfish)

Question 46

Actinopterygii (2)

Answer 46

Ray-finned fish muscles that control fins are within the body 1) Palaeonisciformes 2) Sturgeons (largest freshwater fish)

Question 47

Sarcopterygii

Answer 47

Lobe-finned fish Fleshy fins composed of soft muscles HUMANS derived from fleshy-finned fish

Question 48

subclass of Sarcopterygii (1)

Answer 48

Coelacanth - Vertebrate tiny - Notochord well developed - Swim Bladder