week 9, apr 11th - 15th

Question 1

What did phylum platyhelminthes evolve

Answer 1

Evolved cephalization
Evolved moving in one direction to present head first to detect danger
Evolved bilateral symmetry

Question 2

What is cephalization

Answer 2

Mass of neurons in the head that can detect stimuli

Located in ganglia

Question 3

What is bilateral symmetry

Answer 3

Only one way to cut the animal into two equal halves

Has a head, bottom, right and left sides

Question 4

What is stimuli

Answer 4

Change in the environment

Question 5

What does acoelomate mean

Answer 5

Has no body cavity

Question 6

Name the parts of a cross section of a planaria

Answer 6

Ectoderm, thin body, good surface for gas exchange by simple diffusion
Mesoderm
Endoderm
Gastrovascular cavity, incomplete digestive system, one opening

Question 7

Describe phylum nematoda

Answer 7

Round worms
Nematodes
Mostly parasites

Question 8

Describe phylum nematoda pseudocoelomates

Answer 8

Have a pseudocoelom

Body cavity is not completely linked with mesoderm

Question 9

Describe phylum nematoda coelomates

Answer 9

Have a coelom
True body cavity
Completely linked with mesoderm

Question 10

Describe cross section of a nematode pseudocoelomates

Answer 10

Pseudocoelom
Mesoderm
Ectoderm (cuticle, thick skin)
Endoderm lines the digestive tube, complete digestive system, 2 opening
digestive cavity, evolved from mouth to anus

Question 11

Describe cross section of a nematode coelomates

Answer 11

Endoderm
Ectoderm
Mesdoderm
Coelom: true body cavity

Question 12

Name the 2 types of coelomates

Answer 12

Protostomes

Deuterostomes

Question 13

Name the protostomes phyla

Answer 13

Annelida
Arthropoda
Mollusca

Question 14

Name the deuterostome phyla

Answer 14

Echinodermata

Chordata`

Question 15

Describe protostomes

Answer 15

Spiral change
Form mouth first (blastopore)
Mesoderm origin layer blastopore
Determinate: all cells specialize at the same time

Question 16

Describe deuterostomes

Answer 16

Radial cleavage
Blastopore becomes anus, forms anus first
Mesoderm origin at roof of archenteron
Archenteron, primitive gut (digestive tract)
Indeterminate: not all cells specialize (stem cells)

Question 17

Describe radial cleavage

Answer 17

8 cells embryo
Mitosis
Cleavage = rapid cell division with no cellular growth (no G1)

Question 18

Describe phylum Annelida

Answer 18

Segmented worms (earthworm, sandworm, leech)
Protostome, coelomates
Closed circulatory system, transports blood within blood vessel, using hearts creating a blood movement/pressure
Need moist skin to absorb oxygen and excrete carbon dioxide by simple diffusion

Question 19

What does a sandworm have

Answer 19

Gills called parapodia

Ventral nerve cord

Question 20

Describe the organisms in phylum arthropoda

Answer 20

Insects (6 legs)
Arachnida (spiders, scorpions, ticks, 8 legs)
Crustacea (shrimp, crab, lobster)
Centipede 
Millipede

Question 21

Describe characteristics of phylum arthropoda

Answer 21

Exoskeleton composed of chitin (anchors muscles)
Coelomates
Protostome 
Articulated limbs 
Cephalization (head)
Ventral nerve cord

Question 22

Name the 3 body parts of an insect

Answer 22

Head (sensory)
Thorax (locomotion)
Abdomen

Question 23

What circulatory system does phylum arthropoda have

Answer 23

Open circulatory system

Question 24

Describe open circulatory system of phylum arthropoda

Answer 24

Dorsal heart
Short blood vessels
Ostia = valves to reabsorb hemolymph

Question 25

What is hemolymph in phylum arthropoda

Answer 25

Doesn't transport oxygen

Question 26

Is the open circulatory system of phylum arthropoda good

Answer 26

NO, cannot circulate "blood" without a blood pressure

Question 27

State respiratory systems of phylum arthropoda

Answer 27

Aquatic arthropods have gills | Land/terrestrial = tracheal system (insect, millipedes, centipedes)

Question 28

Name 4 parts of tracheal system (phylum arthropoda) and explain them

Answer 28

``` Spiracle = entry to respiratory system Trachea = wind pipe Airsacs = move the air/ventilate Tracheole = smaller tubes to deliver gases (O2) directly to organs ```

Question 29

Describe phylum mollusca

Answer 29

Coelomate Protostome Spiral cleavage

Question 30

Describe organisms in phylum mollusca that have an open circulatory system

Answer 30

Snails | Bivalves (2 shells) clams, mussels, oysters, scallops

Question 31

Describe organisms in phylum mollusca that have a closed circulatory system

Answer 31

Squid | Octopus

Question 32

Describe phylum mollusca common features

Answer 32

Foot for movement Visceral mass (organs) Mantle secretes shell (if present)

Question 33

What do terrestrial molluscs have

Answer 33

Lungs

Question 34

What do aquatic molluscs have

Answer 34

Gills

Question 35

What are the organisms in phylum echinodermata

Answer 35

Sea star (star fish) Sea urchins Sanddollars Sea cucumbers

Question 36

Describe phylum echinodermata

Answer 36

Coelomates Deuterostomes Radial symmetry as adult Unique water vascular system

Question 37

Describe water vascular system of phylum echinodermata

Answer 37

Madreporite = entry to water vascular system | Tube feet = activated by the water vascular system

Question 38

What does oral side of star fish have (phylum echinodermata )

Answer 38

Mouth | Tube feet

Question 39

What does aboral side of star fish have (phylum echinodermata )

Answer 39

Madreporite | Dermal gills