UNIT 2: KINGDOM ANIMALIA 1 (27)

Question 1

General features of kingdom animalia:

Answer 1

1) Multicellular
2) Heterotrophs
3) No cell walls
4) The ability to move
5) All symmetries
6) All habitats
7) Ability for sexual reproduction, diplontic life cycle (diploid multicellular condition)
8) Specific embryonic development that leads to germ layers and tissue types

Question 2

General features of kingdom animalia (2):

Answer 2

• Part of Opisthokonta
• Sister group with choanoflagellates: share similar DNA, modern sponges have cells very similar to modern choanoflagellates

Question 3

Five key transitions can be noted in animal evolution:

Answer 3

1) Tissue development
2) Symmetry
3) Body cavity formation
4) Segmentation
5) Embryo development differentiation

Question 4

Parazoa

Answer 4

• Para = next to
• Zoo = animal
• Lack defined tissues and organs
• Have the ability to dedifferentiate and re-differentiate their cells

Question 5

Eumetazoa

Answer 5

• Eu = true
• Meta = late
• Zoo = animal
• Have distance and well-defined tissues
• Have irreversible differentiation for most cell types
• Diploblast vs. Triploblast

Question 6

Diploblast

Answer 6

• Di = two
• Blast = to spout
• Two cell layers

Question 7

Ectoderm

Answer 7

• Ecto = outside
• Non-cellular middle
• Endoderm

Question 8

Evolution of symmetry

Answer 8

• Parazoa have no symmetry and Eumetazoa does have symmetry

Question 9

Radial symmetry

Answer 9

• Symmetry around a central axis (EX: starfish or a tulip flower)
• Body parts arranged around central axis
• Can be bisected into two equal halves in any 2-D plane

Question 10

Bilateral Symmetry

Answer 10

• When the body plan of an animal can be divided along a line that separates the animal’s body into right and left halves that are nearly identical of each other
• Bi = two
• Lateral = side
• Only one mirror image
• Other directional bisections
• Directional movement
• Leads to cephalization

Question 11

Cephalization

Answer 11

• The development of sense organs near the front, also known as the head (an organism with a well-developed head is known as highly cephalized)
• Cephalo = head

Question 12

Evolution of the a body cavity:

Answer 12

• Eumetazoa may produce coelom (the body cavity in metazoans)
• =cavity, sounds like ‘seal’
• Space in between tissues, surrounded by mesoderm

Question 13

Acoelomate

Answer 13

• No coelom
• A = without

Question 14

Pseudocoelomate

Answer 14

• Coelom between mesoderm and endoderm
• Pseudo = false

Question 15

Eucoelomate

Answer 15

• Coelom lined on both sides with mesoderm
• Eu = true

Question 16

Evolution of segmentation

Answer 16

• Segmentations caused by Hox genes
• Provides three advantages:
  1) Redundant systems and tissues
  2) Improved locomotion
  3) Regional specialization

Question 17

Blastula

Answer 17

• an animal embryo at the early stage of development when it is a hollow ball of cells
• Occurs through cell division (cleavage)
• A hole forms in the blastula called a blastopore
• Blast = to sprout
• Pore = hole
• Blastopore initiates digestive system development

Question 18

Protostome

Answer 18

• A multicellular organism whose mouth develops from a primary embryonic opening
• Aka if the blastopore become the south
• Proto = first
• Stoma = mouth

Question 19

Phylums that have protostome

Answer 19

• Annelids, arthropods, mollusks, nemerteans nematodes, platyhelminthes, rotifers, tardigrades

Question 20

Deuterostome

Answer 20

• The blastopore (the first opening in cleavage) developing into the anus during embryonic development
• Aka if the blastopore becomes the anus
• Deutero = second

Question 21

Animals with deuterostomes

Answer 21

• Chordates
• Echinoderms

Question 22

Protostome/Deuterostome Differences #1:

Answer 22

1) Cleavage pattern of embryonic cells
- Protostomes = spiral cleavage
- Deuterostomes = radial cleavage

Question 23

Protostome/Deuterostome Differences #2:

Answer 23

2) Development fate of cells
- Protostomes = determine development
- Deuterostomes = indeterminate development

Question 24

Protostome/Deuterostome Differences #3:

Answer 24

3) Origination of Coelom
- Protostomes forms simply and directly from splitting the mesoderm called schizocoely
- = split cavity
- Deuterostomes forms indirectly from outpocketing of the gut called enterocoely
- = stomach cavity

Question 25

Cambrian Explosion

Answer 25

• The time when most of the major groups of animals first appear in the fossil record and resulted in the divergence of most modern metazoan phyla
• 542-488 million years ago marks the most rapid evolution of new animal phyla and animal diversity in Earth’s history
• The curse of the Cambrian Explosion is still debated
• Increasing O2
• Increasing oceanic Ca
• Broad continental shelf
• Hox genes

Question 26

The Hox developmental gene complex evolved:

Answer 26

• It provided a tool that can produce rapid changes in body plan
• Serve as “master control genes” that can turn on or off numbers of other genes
• Encode transcription factors that control the expression of humorous other genes
• Hox genes are homologous across the animal kingdom
• Genetic sequences are similar across most animals, presence in a common ancestor

Question 27

Phylum Porifera

Answer 27

• Sponges
• Pore = hole
• Fer = bearing
• They are parazoans
• No tissue and no symmetry
• Include marine and freshwater species

Question 28

Phylum Porifera Reproduction

Answer 28

• Asexual reproduction = fragmentation
• Sexual reproduction = egg and sperm meet

Question 29

Phylum Porifera Movement:

Answer 29

• Sponge larvae are ciliated/flagellated and able to swim
• Adults are non-motile and attached to a substratum

Question 30

Phylum Porifera Cell Types:

Answer 30

• Inner layer = specialized flagellated cells called choanocytes
• Choana = collar
• Cyte = cell
• Central layer = gelatinous protein-rich matrix called the mesohyl
• = middle matter
• Spicules and spongin

Question 31

Phylum Porifera Filter Feeders:

Answer 31

• Choanocyte flagella draws water/particles/small animals though numbers small pores
• Intracellular digestion
• Intra = within
• Eventually exits from the osculum (a large hole in a sponge through which water leaves from)

Question 32

Phylum Cnidaria Animals:

Answer 32

-Hydroids
- Man O’ Wars
- Sea anemones
- Corals
- Jellyfish
- Box jellyfish

Question 33

Phylum Cnidaria Body Plan:

Answer 33

• Radial symmetry
• Central mouth/anus wreathed with tentacles

Question 34

Phylum Cnidaria Diploblasts:

Answer 34

• Ectoderm and endoderm layers are cellular with tissue
• Middle is made up if non-tissue jelly ir mesoglea
• = middle glue

Question 35

Phylum Cnidaria Facts:

Answer 35

• 99% are marine species
• Dimorphic: 2 body forms (occurring in or representing 2 body forms)
• Medusa and polyp
• Same tissues in both
• Basically flipped over versions of one another

Question 36

Phylum Cnidaria Lifecycle:

Answer 36

• Polyps may be solitary or branch their guts to form colonies
• Polyps can bud to asexually reproduce
• Some groups alternate between polyps and medusas

Question 37

Medusa

Answer 37

• A reproductive stage that creates sperm/ egg and grow off of gonozooid polyps

Question 38

Cnidarians Specialized Cells:

Answer 38

• Cnidarians have unique specialized cells on their epidermis called cnidocyte
• Cnido = nettle = to sting
• Cyte = cell

Question 39

Cnidarians Nematocysts:

Answer 39

• Large stinging organelles called nematocysts
• Nema = thread
• Cyst = sac
• Contain barbs at the base of a long coiled thread
• Hair-like projection extends to outside the cell and sensitive to tactile stimulation
• Mostly carnivorous

Question 40

Nematocysts Digestion:

Answer 40

• Extracellular digestion
• Extra = outside
• Digestion veins with fragmentation in the gastrovascular cavity (humans do this too)
• No circulatory, respiratory, or excretory systems