Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Organisms 2 > Cnidaria and Ctenophora > Flashcards

Cnidaria and Ctenophora Flashcards

1
Q

How can animal body plans be characterized?

A
  • Number of germ layers (no germ layers, diploblastic, triploblastic)
  • Types of body cavities (coelomate, pseudocoelomate, acoelomate, complete gut, blind gut)
  • Organismal complexity (protoplasmic, cellular, cell-tissue, tissue-organ, organ-system)
  • Symmetry (no symmetry, spherical, radial, biracial, bilateral)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the types of symmetry?

A
  • Asymmetrical
  • Spherical (ball shaped)
  • Radial (tube or vase like)
  • Biradial (radial with an additional paired structure)
  • Bilateral (right and left sides)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Explain asymmetrical

A

no symmetry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Explain spherical symmetry

A
  • Any plane passing through the center divides the body into mirrored halves
  • Best suited for floating and rolling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Explain radial symmetry

A
  • Body divided into similar halves by more than two planes passing through the longitudinal axis
  • Can interact with the environment in all directions
    Usually sessile, free floating, or weakly swimming animals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Explain biradial symmetry

A
  • Variant form of radial symmetry

- Radially symmetrical with the exception of a body part that is paired

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain bilateral symmetry

A
  • Divided along a sagittal plane into two mirror portions forming right and left halves
  • Much better for directional (forward) movements
  • Associated with cephalization
  • Also has mouth in front to allow for more efficient feeding and detection of prey
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is cephalization?

A

The differentiation of a head region and the concentration of nervous tissues and sense organs in the front area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the planes of symmetry?

A
  • Frontal plane (coronal plane)
    Divides body into dorsal and ventral halves
  • Sagittal plane
    Divides body to right and left
  • Transverse plane (cross section)
    Divides body into anterior and posterior halves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Regions of bilaterally symmetrical animals

A
  • Anterior (head end)
  • Posterior (tail end)
  • Dorsal (back side)
  • Ventral (bottom or belly side)
  • Medial (midline of body)
  • Lateral (right and left sides)
  • Distal (parts farther from the middle of body)
  • Proximal (parts are nearer the middle of body)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are Cnidaria and Ctenophora?

A
  • Phylum Cnidaria: hydroids, anemones, jellyfish and corals
  • Radial symmetry
  • Cell tissue level of biological organization (some organs may occur)
  • Diploblastic
  • Blind gut
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the Phylum Cnidaria?

A
  • Mostly sessile or slow moving
  • Efficient predators
  • Algae frequently live as mutualists with Cnidarians
  • Mostly marine, some freshwater, no terrestrial
  • Abundant in shallow marine habitat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the classes in the Phylum Cnidaria?

A
  • Class Hyrdozoa (includes hydroids, fore corals, Portuguese man of war)
  • Class Scyphozoa (true jellyfish)
  • Class Cubozoa (box jellyfish)
  • Class Anthozoa (largest class and includes sea anemones and corals)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the classifications?

A
  • Metazoa
    All animals
  • Eumetazoa
    Multicellular animal with distinct germ layers
    Has true tissues
    Includes Cnidaria and Ctenophora but excludes Porifera
    All eumetazoans other than Cnidarians and Ctenophores
    exhibit primary bilateral symmetry
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are there forms?

A
  • Two morphological types
    Polyp (sedentary or sessile)
    Medusa (floating or free swimming)
  • Many Cnidarians are dimorphic; exhibit both polyp and medusa forms
  • In some species, only one form exists
  • Both medusa and polyp forms are diploblastic (two tissue layers)
  • In between tissue layers is a jellylike layer of mesoglea
  • Mesoglea is thicker in the medusa form (gives it buoyancy)
  • Medusae are commonly called jellyfish or jellies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the polyp form?

A
  • Tube shaped
  • Tend to be sedentary or sessile
  • Mouth surrounded by tentacles
  • Can be attached to substratum by a pedal disc
17
Q

What is the medusa form?

A
  • Umbrella shaped
  • Floating or free swimming
  • Mouth centred on concave side
  • Tentacles extend from rim of umbrella shape
18
Q

What is the Cnidarian physiology?

A
  • Respiration (by diffusion)
  • Digestion
    Mouth opens into gastrovascular cavity
    Incomplete or blind gut
    Use both extracellular and intracellular digestion (undigested
    particles carried back to gastrovascular cavity by amoeboid
    cells)
19
Q

What is extracellular digestion?

A

enzymes discharged into gastrovascular cavity

20
Q

What is intracellular digestion?

A

phagocytosis of food particles

21
Q

What is the reproduction of Cnidarians?

A
  • Varies among classes
  • Most have free swimming planar larva
  • Planula settles and metamorphoses into a polyp
  • Polyps can reproduce asexually and sexually
    Into more polyps or into medusae
    Colonies form when polys reproduce asexually but stay
    attached
    Polyps within colony specialize for certain functions
  • Medusae reproduce sexually
22
Q

What is the lifer cycle of Aurelia?

A
  • Sperm fertilizes egg in gastric pouch
  • Zygote develops on arms of female
  • Planula larva attaches and becomes a scyphistoma (polyp form)
  • Scyphistoma can bud to form other polyps (asexual reproduction)
  • Becomes a strobila
  • Releases saucer like buds called ephyrae
  • Ephyrae into mature jellyfish (medusa form)
23
Q

What is their locomotion?

A
  • Some polyps are permanently attached (sessile)
  • Hydra and sea anemones can move slowly by gliding on pedal disc
    Hydra can also use a measuring worm movement
    Sea anemones occasionally swim
  • Medusae can move freely
    Swim by contracting the bell
    Usually contract several times and move generally upward
    Then sink slowly
24
Q

A fearsome tiny weapon

A
  • All Cnidarians have tentacles with stinging cells at tip
  • Stinging cells are called cnidocytes
  • Cnidocytes (cell that holds cnida)
  • Cnida
    Singing organelle
    Nematocyst: most common type of cnida
    Many nematocyst have a toxin which paralyses prey
  • Cnidocil
    Triggers the nematocyst to fire
25
Q

Explain the class Hydrozoa

A
  • Typical life cycle includes asexual polyp and sexual medusa stage
  • Freshwater hydra have no medusa stage
  • Others have no polyp stage and occur only as medusa
26
Q

Explain class Scyphozoa

A
  • True jellyfish
  • Dioecious
  • Internal fertilization
  • Exhibit medusa and polyp form during life cycle
    Medusa reproduces sexually
    Polyp reproduces asexually
27
Q

Explain class Cubozoa

A
  • Box jellyfish
  • Medusa is prominent form
    Polyp is often uncharacterized
  • Medusa bells are almost square
  • Tentacles occur at corners of square
  • Strong swimmers and predators
  • Stings from some species can be fatal to humans
28
Q

Explain class Anthozoa

A
  • Polyps with a flower-like appearance: sea anemones, corals, sea fans
  • No medusa stage
  • Sexual and asexual reproduction occur in polyp phase
  • All marine
  • Solitary or colonial
29
Q

What is the Phylum Ctenophora?

A
  • Cell tissue level of biological organization (some organs may occur)
  • Diploblastic
  • Blind gut
  • Approx. 150 species
  • All marine, especially in warm waters
  • Commonly called sea walnuts or comb jellies
  • Name comes from comb-like plates that they use for locomotion (combs are made from fused cilia)
  • Do not have nematocyst
    Colloblasts line tentacles (release sticky substance instead of
    venom
    One species recycles nematocysts from Cnidarian medusa

Organisms 2 (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions